Health Notes

• CHAPTER 4 HEALTH NOTES!
  There are physical changes like growth spurts and weight gain.
  Your body's reproductive organs start to develop and mature as you near adulthood.
  
  MALE:
  The male reproductive system serves two important functions:
  (1) it produces sperm
  (2) it produces hormones that assist in the growth and development of young men.
  
  The internal male organs are the testes, epididymis, vas deferens, ejaculatory duct, prostate gland, seminal vesicles, and bulbourethral (Cowper's) glands.
  The external penis surrounds the urethra, which transports both urine and sperm (but not at the same time).
  The scrotum, a sac-like structure that holds the testes away from the body, is also an external structure (see figure 4-1).
  
  
  Testes
  · The testes are the male sex glands responsible for the production of sperm cells and the male hormone testosterone.
  · They are inclosed by the scrotum. The scrotum is a skin outpouching of the abdomen consisting of loose skin and superficial fascia. It functions to enclose and protect the testes and maintains a constant temperature about 3 degrees Fahrenheit below normal body temperature for optimal sperm production.
  ·
  Sperm
  · The process of sperm production is called spermatogenesis.
  · Takes about seventy-four days for human males to create sperm through spermatogenesis.
  · Seminiferous tubules are tightly coiled tubules in the testes where spermatogenesis occurs. In these tubules, immature sperm cells, or spermatogonia, grow into fully-matured sperm cells called a spermatozoon.
  · Another type of cell called sertoli cells provide a barrier for the developing sperm cells to ensure the maturation process takes place correctly.
  · Spermatozoa (mature sperm cells) mature at a rate of about 300 million per day.
  · Once ejaculated through the penis, they have a life expectancy of about forty-eight hours.
  Each spermatozoon (commonly called sperm) has a head, midpiece, and tail.
  · The head is the portion of the sperm that contains the genetic material (DNA) for a potential offspring.
  · The surface of the head is made from acrosome, a dense, granular material that contains enzymes to help the sperm penetrate the egg cell.
  · The midpiece is the portion of the sperm that has numerous mitochondria, where energy for the movement of the sperm is made.
  · The tail propels the sperm forward.
  Testosterone and Puberty
  · the principle male hormone
  · controls growth and development,
  · maintains the male sex organs,
  · causes hairline recession,
  · stimulates bone growth,
  · stimulates anabolism (the phase of metabolism when the nutrients and other substances are broken down and used by the body) of protein,
  · and helps in muscular development.
  · Testosterone is also responsible for the closure of epiphyseal plates
  · which are the growth plates in bones
  · It influences sexual behavior and causes the final maturation of sperm.
  
  Puberty begins at about age ten or eleven and is completed around age fifteen to seventeen. During puberty (a term which literally means "marriageable age"), secondary male sex characteristics are developed.
  Testosterone aids in the development of pubic, axillary, and chest hair; facial hair growth; and the deepening of the voice and enlargement of the voice box.
  Potential for sexual reproduction is reached.
  Movement from the Testes to Outside the Body
  1. From the highly coiled seminiferous tubules of the testes, the sperm move through a series of straight tubules to a network of ducts in the testes called the rete testis.
  2. After the sperm leave the testes, they continue their journey to the epididymis—a comma-shaped organ that lies along the posterior border of the testes.
  · The epididymis consists mostly of a tightly coiled tube called the ductus epididymis, which measures about twenty feet in length when stretched out!
  · This is the site of further sperm maturation (sperm requires about ten to fourteen additional days here to completely mature).
  3. Sperm may remain in the ductus epididymis for up to four weeks, after which they are either expelled or reabsorbed by the body.
  4. The ductus deferens (or vas deferens) is the next location for the sperm.
  · This organ is a long tube (eighteen inches) that serves as the passageway for sperm from the epididymis to the urethra. Near the end of the vas deferens are the ejaculatory ducts—tubes just behind the urinary bladder formed by the union of the tubes from the seminal vesicle and the vas deferens.
  5. The ejaculatory ducts eject sperm into the urethra just prior to ejaculation.
  The urethra is the end tube for both the reproductive and urinary systems. It is a narrow tube that spans from inside the body to the end of the penis. The urethra serves as the passageway for urine or spermatozoa to leave the body and enter the external environment. The urethra measures about eight inches in length, throughout which there are four portions:
  Prostatic urethra—the portion of the urethra that passes through the prostate gland
  Membranous urethra—the middle portion of the urethra
  Spongy urethra—the portion of the urethra contained in the penis
  External urethral orifice—external opening of the urethra
  The penis is the portion of the male anatomy used to introduce the sperm into the female vagina during intercourse. It is cylindrical in shape and consists of the root, body, and glands.
  The root is the portion of the penis that is attached to the pubic area, or the lower abdomen. The body is composed of three cylindrical masses of tissue each bound by fibrous tissue. Under the influence of sexual stimulation (visual, tactile, auditory, olfactory, and imaginative), the arteries supplying the penis dilate (or open up), large quantities of blood enter the vessels, and an erection occurs. The glans penis is the slightly enlarged end, or tip, of the penis that is covered by loose-fitting skin called the foreskin or prepuce. The foreskin is removed during a surgical procedure called a circumcision.
  · Semen, or seminal fluid, is a mixture of sperm with the secretions of the accessory male sex glands, which consist of the seminal vesicles, prostate gland, and bulbourethral glands (Cowper's gland).
  · The average volume of semen for ejaculation is 2.5 to 5 milliliters, and there are about 50 to 150 million sperm per milliliter of semen.
  · If semen contains less than 20 million sperm per milliliter, the male is considered infertile.
  · Seminal vesicles—convoluted pouch-like structures lying at the back of the urinary bladder at the base—secrete an alkaline, thick fluid rich in fructose, a carbohydrate used as an energy source for the sperm. ________This fluid makes up about 60 percent of the volume of the semen, and the alkaline nature of this fluid allows the sperm to survive in the acidic female reproductive tract.
  · Prostate gland is a single, donut-shaped gland about the size of a chestnut located below the urinary bladder and surrounding the urethra.
  · It secretes a slightly acidic fluid rich in citric acid, prostatic acid phosphates, and prostaglandins.
  · It makes up about 13 percent to 33 percent of the semen.
  · The chemicals found in the semen help to contribute to sperm movement and life.
  · It is important to note that the prostate gland is often the site of cancerous cell growth in older males.
  Bulbourethral glands (Cowper's glands) are pea-sized glands located just below the prostate gland on either the side of the urethra. These glands also secrete an alkaline substance that helps neutralize the acidic environment of the urethra.
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  Hernia
  · A hernia occurs when part of an organ, usually the intestines, pushes through a membrane or muscle that contains an organ.
  · A common hernia is a inguinal hernia, which occurs in a weak spot near the top of the scrotum.
  · Surgery can correct the problem.
  Prostate Cancer
  · Prostate cancer is a common cancer in older males since the risk of prostate cancer increases with age.
  · It can be effectively treated when detected early; therefore, it is important that males over the age of 40 receive an annual physical to determine the size of the prostate.
  · Cancer of the prostate can be detected with a blood test known as a PSA. If the PSA is high, biopsy of the prostate to check the cancerous cells is the next step.
  Testicular Cancer
  · Testicular cancer is the most common cancer in men ages 15-24.
  · Check for the presence of a hard, painless lump. If the lump is painful, it is most likely a bruise.
  
  The best time to perform the examination is after a warm bath or shower, when the scrotal skin is the most relaxed. (Scrotal skin is on the scrotum, the sac in which the testicles are normally found.)
  Roll each testicle gently between the thumb and fingers of both hands. A normal testicle is smooth, egg-shaped, and somewhat firm to the touch. (Behind each testicle is the epididymis, which carries sperm away from the testicle.)
  If you find any hard lumps or nodules, or if there is any change in the shape, size, or texture of the testicles, consult a physician promptly. These signs may not indicate cancer, but only your physician can make a definite diagnosis.
  The female reproductive system serves four important functions:
  (1) It produces eggs,
  (2) It is the site of fertilization,
  (3) it provides nourishment and protection for the fertilized egg as it develops into a fetus, and further develops into a baby capable of life outside the mother's body, and
  (4) It produces hormones.
  Ovaries
  · The ovaries are the primary female organs.
  · Two almond-shaped glands, approximately one inch long, located within the pelvic cavity.
  · Two functions: To produce the hormones estrogen and progesterone and to produce eggs.
  · The production and maturation of eggs continues during puberty (the eggs are actually produced before she is born).
  · This process is under the control of the two above-mentioned hormones.
  · The release of eggs from the ovaries occurs in a process known as ovulation
  Uterine Tubes
  · The uterine tubes (Fallopian tubes) are four inches long and one-fourth of an inch wide.
  · There are two uterine tubes, one located on each side of the uterus.
  · The uterine tubes are responsible for transporting eggs from the ovaries to the uterus.
  · On the side of the uterine tube that is attached to the ovary, the tube opens and expands into a funnel known as the infundibulum. It has long, finger-like projections known as fimbriae.
  · Movement of the egg within the uterine tube occurs as a result of muscle contractions and the movement of small hairs located within the tube.
  · Fertilization will occur if sperm cells are present while the egg is in the uterine tubes.
  Uterus
  The uterus is an organ located in the pelvis that is shaped like an upside-down pear. The uterus is three inches long and two inches wide. The most upper portion is called the fundus, the middle section is called the body, and the lower third is called the cervix. The wall of the uterus is composed of three layers. The inner lining is the endometrium and is where a fertilized egg implants. If fertilization does not occur while in the uterine tubes, the lining of the uterus is lost in a process known as menstruation, consisting of periods (see section entitled "The Menstrual Cycle"). The second layer is the myometrium, or muscle layer. The muscle contractions help to push the fetus outside during delivery. The outer layer, or perimetrium, provides protection for the uterus.
  Vagina
  The vagina is a four-inch-long muscular tube attached to the cervix and located below the uterus. It leads to the outside of the body. The vagina is very elastic and can stretch many times its normal size. The vagina has four functions: (1) it serves as a receptacle for the erect penis, (2) it is where the sperm is deposited during intercourse, (3) it serves as the birth canal for the delivery of the fetus, and (4) it is an exit for the tissue associated with menstruation. Just inside the vagina are two glands called Bartholin's (vestibular) glands. These glands secrete small amounts of fluid and mucous to lubricate the opening of the vagina prior to sexual intercourse.
  Vulva
  The vulva contains the female external reproductive organs. The labia majora encloses and protects the external reproductive organs. It is composed of skin and fat. The front region of the labia majora is called the mons pubis, which covers the front portion of the pubic bone. The labia minora lies inside of the labia majora. It forms a covering around the clitoris. The clitoris is a small projection at the front end of the vulva. It contains many sensory nerve fibers, as well as erectile tissue.
  Breasts
  There are additional female reproductive structures not located within the pelvic cavity. They are known as the breasts. The breasts are composed of fat to protect the mammary glands, which are specialized to produce milk. Milk provides newborn babies with nourishment as well as antibodies, which protect against disease. A nipple is in the center of each breast and is surrounded by a darkened area of skin called the areola. The nipple is an opening that serves as an exit for the milk. The growth of breasts and mammary glands is under the control of the hormone estrogen and occurs during puberty.
  The Menstrual Cycle
  The brain produces two hormones in the pituitary gland
  The first hormone, follicle-stimulating hormone (FSH) , is responsible for the growth and maturation of eggs in the ovary before they are released into the Fallopian tube.
  While the eggs are maturing, FSH also stimulates the production of another hormone: a group of chemicals known as the estrogens.
  The estrogens have many effects including the building of the uterine lining (endometrium), breast development, and increased fat deposits in the buttocks and thighs.
  In other words, the estrogens prepare the body for possible pregnancy.
  These changes occur during the first thirteen days (the first half) of the menstrual cycle, which is called the preovulatory phase.
  
  · At the midpoint of the cycle, or day fourteen, the pituitary gland increases its production of the second hormone, luteinizing hormone
  
  · At the midpoint of the cycle, or day fourteen, the pituitary gland increases its production of the second hormone, luteinizing hormone (LH). This second hormone allows the mature egg to rupture from the ovary (called ovulation) and enter into the uterine tube. The postovulatory phase has begun. LH also encourages the formation of a "scar" within the ovary. This "scar" is where the egg was located before ovulation and is called the corpus luteum, and it produces the hormone progesterone. Progesterone's role is to increase the blood supply to the endometrium. This is important; if the egg is fertilized by a sperm, it will implant into the uterus where it will stay for the next nine months.
  · If fertilization does not take place, the menses phase begins and the corpus luteum shrinks in size. The levels of progesterone and estrogen drop, and the uterine lining (endometrium) is lost during the monthly blood flow or period. The blood and some of the endometrial cells will exit the body through the vagina. The unfertilized egg will also disintegrate. Since the first day of one's period is so highly visible, it is referred to as the first day, or day one, of the menstrual cycle. The average menstrual cycle is twenty-eight days, but an individual female's cycle may have more or less days.
  PMS (Premenstrual Syndrome)
  PMS is a collection of physical and mental symptoms that can disrupt a woman's life. The symptoms include the following:
  physical discomfort
  swelling of hands and feet
  painful menstruation
  backaches
  fatigue
  irritability
  depression
  breast tenderness
  abdominal bloating and cramping
  constipation or diarrhea
  headaches
  weight gain of three to nine pounds associated with the menstrual flow
  hunger and binges especially for sweet or salty foods
  
  The treatment
  · Medications and lifestyle changes.
  · The lifestyle changes involve dietary changes, exercise, and stress reduction.
  · Nutritional supplements such as vitamin B6 or calcium may be added to the diet.
  · Analgesics, such as ibuprofen, may be given for pain.
  · Sometimes a woman may need antianxiety drugs or antidepression drugs when she is having PMS.
  · She may also need to begin hormone therapy
  Toxic Shock Syndrome (TSS)
  · Toxic Shock Syndrome (TSS) is an infection that can be associated with tampon use during menstruation.
  · Staphylococcus aureus is the bacteria responsible for TSS.
  · The symptoms of toxic shock syndrome include
  1. high fever,
  2. headache,
  3. discharge from the vagina,
  4. diarrhea,
  5. nausea,
  6. vomiting,
  7. severe fatigue,
  8. and a red rash that looks like a sunburn.
  
  · Symptoms may get worse as the infection grows.
  · The major problem with TSS is that it can cause failure of the kidney, heart, and liver.
  · Treatment includes antibiotics and other medications to control the infection.
  · It is important to change tampons regularly to reduce the risk of this infection.
  · It is also suggested that women consider using sanitary napkins instead of tampons while sleeping
  Maintaining the Health of the Female Reproductive System
  Daily care for the female reproductive system revolves around cleanliness. Once the female goes through puberty, there may be a slight vaginal odor, so cleanliness is especially important. Tampons and sanitary napkins are used during a female's period to absorb the menstrual flow. For hygienic purposes and to reduce the risk of infections like toxic shock syndrome, it is recommended that tampons be changed every few hours. Women should be sure to read the package inserts for more detailed information before using a product. Feminine deodorant sprays and douches are not usually necessary and may irritate the delicate vaginal tissues. 197
  Breast Self-Exams
  It is important that females do breast self-examinations (BSE) on a monthly basis (see figure 4-5). It is probably best to do this right after one's period has ended when the breasts are not as sore. Regular inspection of the breasts will help you to know what your normal breast tissue should look like.
  
  Mammograms
  After the age of thirty-five
  This procedure x-rays the breasts and helps identify the presence of abnormalities
  It is estimated that one in every eight women will be diagnosed with breast cancer some time in her life
  Early detection means less invasive surgery as well as less chemotherapy or radiation as follow-up therapy.
  note that men can also be victims of breast cancer, although it is rare.
  Pap Smears
  Starting around the age of 18-20,
  cell-screening test that helps to detect cancer of the cervix.
  The cervix is the lower part of the uterus.
  Cervical cancer eventually kills one-third of women who are diagnosed with it.
  Remember, the key to fighting and winning the war with cancer is early detection and early treatment.
  Five pairs of analogous organs are discussed below:
  Male testes are similar to female ovaries. Both ovaries and testes produce hormones. The testes produce the hormone testosterone, which is responsible for male sex characteristics. The ovaries produce the hormones estrogen and progesterone, which are responsible for female sex characteristics and the growth and development of the uterus lining. Also, both organs produce gametes: the testes produce sperm while the ovaries produce eggs.
  The male ductus deferens is similar to the female uterine tubes. The ductus deferens is composed of three layers lined with cilia (small hairs) and serves as a passageway for sperm. The uterine tubes are also composed of three layers lined with cilia. The uterine tubes serve as a passageway for the eggs and sperm and is the site of fertilization.
  The male scrotum is similar to the female labia majora. Both function to enclose and protect external reproductive organs.
  The male penis is similar to the female clitoris. The penis and the clitoris contain many sensory nerve fibers and erectile tissue.
  The male bulbourethral glands are similar to the female vestibular glands. The secretion of the bulbourethral glands (Cowper's glands) neutralizes the acid of the urethra and lubricates the tip of the penis prior to intercourse. The vestibular glands (Bartholin's glands) lubricate the opening to the vagina prior to intercourse.
  Factors that affect the aging process include genetics, living conditions, nutritional choices over the years, and socioeconomic status.
  Females
  As the female reproductive system ages, there is a decrease in estrogen and progesterone, which causes the vaginal walls and supporting tissues of the uterus to thin.
  The breasts sag as the fat is redistributed.
  As a woman approaches fifty, her ovaries gradually stop producing estrogen.
  This causes a set of symptoms that are collectively known as menopause.
  Symptoms of menopause include hot flashes in the face and upper chest, headaches, dizziness, heart beat irregularities, and joint pain.
  The loss of estrogen may predispose a woman to osteoporosis, which is the loss of bone calcium and mass.
  Some women also become moody, depressed, tired, irritable, or forgetful.
  Males
  aging tends to shrink the size of the testes;
  this shrinking reduces testosterone and sperm production.
  Physical changes can cause mental or emotional changes sometimes called a "mid-life crises."
  Many men and women alike may experience this.
  Men, just like women, usually take time to reassess their lives, set new goals, and re-evaluate priorities.
  
  produces part of the fluid portion of the semen; neutralizes the acid urethra
  the muscular sac-like structure that holds the testes away from the body
  the male sex hormone that helps in male sex characteristics as well as muscle and bone development
  the male reproductive organ that helps to transfer sperm into the woman’s body
  the male reproductive cells that contain the man’s genetic information for offspring
  the long tube-like passageway which connects the epididymis to the ejaculatory duct; transports sperm as they leave the body
  the foreskin which covers the tip of the penis
  the tube that runs through the center of the penis; it can transport urine or sperm (semen) but not at the same time
  the male organ which produces sperm and testosterone
  the coiled structures located on top of the testes where sperm matures
  the donut-shaped gland at the top of the urethra that produces some of the fluid in the semen
  
  
  How Does Fertilization Occur?
  · After sperm cells are deposited in the vagina through sexual intercourse, they travel upward to the egg by means of their tails.
  · Sperm movement is also assisted by muscle contractions of the uterus and uterine tubes (fallopian).
  · After the egg bursts from the ovary, it is swept into the uterine tubes by the tiny fimbriae.
  · Fertilization, or conception, takes place within the uterine tubes.
  · When the sperm reaches the egg, it penetrates the tough membrane of the egg by enzymes found within the sperm.
  · The nuclei of the egg and sperm fuse together, producing a cell known as a zygote.
  · A zygote is the first fertilized cell.
  · Once the zygote is formed, cleavage begins.
  · Cleavage is a process of cell division in which the next cells are smaller than the ones before.
  · The zygote divides into two, then four, eight, and finally sixteen cells.
  · The mass of sixteen cells is known as a morula, and it continues passage through the uterine tube.
  · It is transported down to the uterus by the uterine tube's muscle contractions and the sweeping motion of the fimbriae.
  · Three days have passed by now.
  · The morula enters the uterus and remains free-floating within the uterus for another three days.
  · During this time the mass of cells becomes hollow, which is known as a blastocyst.
  · The blastocyst implants in the lining of the uterus. This occurs approximately seven days after fertilization.
  · Once implantation has occurred, the cluster of cells is called an embryo.
  · The embryo is about the size of a pinhead.
  ·
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  Role of Genetics
  · Located within the center nuclei of both eggs and sperm is genetic material, or DNA.
  · DNA is found in sticky, stringy material known as chromosomes.
  · Each cell in the human body has forty-six chromosomes—except eggs and sperm, which each have twenty-three chromosomes.
  · When fertilization occurs, the nuclei of an egg and sperm fuse together, forming a zygote with forty-six chromosomes.
  · The DNA controls all aspects of growth and development in the zygote by controlling what chemicals its cells make, which leads to what types of cells they become.
  · Genetics is the study of how information in the form of DNA is passed from parent to offspring.
  · DNA is subdivided into specific units called genes.
  · These genes control specific traits such as height, hair color, eye color, and blood type. They may even control the offspring's susceptibility to some diseases such as cancer.
  · Some genes are dominant, which means the traits they control will be present in the offspring even if the offspring only received that dominate gene from one parent.
  · Other genes are recessive. The traits these genes control only show up if the offspring receives that recessive gene from both parents.
  · There may also be genetic mistakes when DNA makes copies of itself to form new cells.
  · These mistakes are known as mutations.
  · A mutation may involve only one small section of the DNA on a chromosome, or it may impact the whole chromosome.
  · Sometimes these mutations involve a tiny piece of the gene called a nucleotide, which can be in an incorrect order.
  · This may cause problems for the body because it cannot make its needed proteins. This occurs in disorders such as sickle-cell anemia.
  · Sickle-cell anemia is a genetic blood disorder in which the red blood cells are abnormally shaped like a sickle instead of having nice, round, smooth edges.
  · These blood cells can stick together in the blood vessels and cause pain and other problems.
  · Other mutations involve entire extra or missing chromosomes. Down's syndrome results in cells that have forty-seven chromosomes instead of the usual forty-six. People with Down's syndrome suffer from mental challenges and physical defects and have a distinct facial appearance. While people with Down's syndrome have one extra chromosome, those with Turner's syndrome are missing one. Turner's syndrome occurs when a female embryo has only one sex-linked chromosome instead of two (see next paragraph for more information on sex-linked chromosomes). This reduces the female's chromosome number from forty-six to forty-five. Females with Turner's syndrome are shorter than usual and have a webbed neck. They are also infertile (cannot produce offspring).
  · On another hand, some disorders may affect genes only located on the sex chromosomes—which are XX for females and XY for males. Examples of these sex-linked disorders are color-blindness and hemophilia. Color blindness occurs when the nerves in the eye carry a genetic disorder, preventing them from seeing some colors—like red and green, for example.
  · Hemophilia is a genetic disorder that does not allow the blood to clot properly.
  · Both of these disorders are located on the X chromosome.
  · Note that if there is another X chromosome present that does not have the disorder, the disorder will not show up.
  · Since males only have one X chromosome, they show these disorders more often than females.
  
  NEXT IS CHAPTER 4 PG. 6!

• CHAPTER 4 HEALTH NOTES!
  There are physical changes like growth spurts and weight gain.
  Your body's reproductive organs start to develop and mature as you near adulthood.
  
  MALE:
  The male reproductive system serves two important functions:
  (1) it produces sperm
  (2) it produces hormones that assist in the growth and development of young men.
  
  The internal male organs are the testes, epididymis, vas deferens, ejaculatory duct, prostate gland, seminal vesicles, and bulbourethral (Cowper's) glands.
  The external penis surrounds the urethra, which transports both urine and sperm (but not at the same time).
  The scrotum, a sac-like structure that holds the testes away from the body, is also an external structure (see figure 4-1).
  
  
  Testes
  · The testes are the male sex glands responsible for the production of sperm cells and the male hormone testosterone.
  · They are inclosed by the scrotum. The scrotum is a skin outpouching of the abdomen consisting of loose skin and superficial fascia. It functions to enclose and protect the testes and maintains a constant temperature about 3 degrees Fahrenheit below normal body temperature for optimal sperm production.
  ·
  Sperm
  · The process of sperm production is called spermatogenesis.
  · Takes about seventy-four days for human males to create sperm through spermatogenesis.
  · Seminiferous tubules are tightly coiled tubules in the testes where spermatogenesis occurs. In these tubules, immature sperm cells, or spermatogonia, grow into fully-matured sperm cells called a spermatozoon.
  · Another type of cell called sertoli cells provide a barrier for the developing sperm cells to ensure the maturation process takes place correctly.
  · Spermatozoa (mature sperm cells) mature at a rate of about 300 million per day.
  · Once ejaculated through the penis, they have a life expectancy of about forty-eight hours.
  Each spermatozoon (commonly called sperm) has a head, midpiece, and tail.
  · The head is the portion of the sperm that contains the genetic material (DNA) for a potential offspring.
  · The surface of the head is made from acrosome, a dense, granular material that contains enzymes to help the sperm penetrate the egg cell.
  · The midpiece is the portion of the sperm that has numerous mitochondria, where energy for the movement of the sperm is made.
  · The tail propels the sperm forward.
  Testosterone and Puberty
  · the principle male hormone
  · controls growth and development,
  · maintains the male sex organs,
  · causes hairline recession,
  · stimulates bone growth,
  · stimulates anabolism (the phase of metabolism when the nutrients and other substances are broken down and used by the body) of protein,
  · and helps in muscular development.
  · Testosterone is also responsible for the closure of epiphyseal plates
  · which are the growth plates in bones
  · It influences sexual behavior and causes the final maturation of sperm.
  
  Puberty begins at about age ten or eleven and is completed around age fifteen to seventeen. During puberty (a term which literally means "marriageable age"), secondary male sex characteristics are developed.
  Testosterone aids in the development of pubic, axillary, and chest hair; facial hair growth; and the deepening of the voice and enlargement of the voice box.
  Potential for sexual reproduction is reached.
  Movement from the Testes to Outside the Body
  1. From the highly coiled seminiferous tubules of the testes, the sperm move through a series of straight tubules to a network of ducts in the testes called the rete testis.
  2. After the sperm leave the testes, they continue their journey to the epididymis—a comma-shaped organ that lies along the posterior border of the testes.
  · The epididymis consists mostly of a tightly coiled tube called the ductus epididymis, which measures about twenty feet in length when stretched out!
  · This is the site of further sperm maturation (sperm requires about ten to fourteen additional days here to completely mature).
  3. Sperm may remain in the ductus epididymis for up to four weeks, after which they are either expelled or reabsorbed by the body.
  4. The ductus deferens (or vas deferens) is the next location for the sperm.
  · This organ is a long tube (eighteen inches) that serves as the passageway for sperm from the epididymis to the urethra. Near the end of the vas deferens are the ejaculatory ducts—tubes just behind the urinary bladder formed by the union of the tubes from the seminal vesicle and the vas deferens.
  5. The ejaculatory ducts eject sperm into the urethra just prior to ejaculation.
  The urethra is the end tube for both the reproductive and urinary systems. It is a narrow tube that spans from inside the body to the end of the penis. The urethra serves as the passageway for urine or spermatozoa to leave the body and enter the external environment. The urethra measures about eight inches in length, throughout which there are four portions:
  Prostatic urethra—the portion of the urethra that passes through the prostate gland
  Membranous urethra—the middle portion of the urethra
  Spongy urethra—the portion of the urethra contained in the penis
  External urethral orifice—external opening of the urethra
  The penis is the portion of the male anatomy used to introduce the sperm into the female vagina during intercourse. It is cylindrical in shape and consists of the root, body, and glands.
  The root is the portion of the penis that is attached to the pubic area, or the lower abdomen. The body is composed of three cylindrical masses of tissue each bound by fibrous tissue. Under the influence of sexual stimulation (visual, tactile, auditory, olfactory, and imaginative), the arteries supplying the penis dilate (or open up), large quantities of blood enter the vessels, and an erection occurs. The glans penis is the slightly enlarged end, or tip, of the penis that is covered by loose-fitting skin called the foreskin or prepuce. The foreskin is removed during a surgical procedure called a circumcision.
  · Semen, or seminal fluid, is a mixture of sperm with the secretions of the accessory male sex glands, which consist of the seminal vesicles, prostate gland, and bulbourethral glands (Cowper's gland).
  · The average volume of semen for ejaculation is 2.5 to 5 milliliters, and there are about 50 to 150 million sperm per milliliter of semen.
  · If semen contains less than 20 million sperm per milliliter, the male is considered infertile.
  · Seminal vesicles—convoluted pouch-like structures lying at the back of the urinary bladder at the base—secrete an alkaline, thick fluid rich in fructose, a carbohydrate used as an energy source for the sperm. ________This fluid makes up about 60 percent of the volume of the semen, and the alkaline nature of this fluid allows the sperm to survive in the acidic female reproductive tract.
  · Prostate gland is a single, donut-shaped gland about the size of a chestnut located below the urinary bladder and surrounding the urethra.
  · It secretes a slightly acidic fluid rich in citric acid, prostatic acid phosphates, and prostaglandins.
  · It makes up about 13 percent to 33 percent of the semen.
  · The chemicals found in the semen help to contribute to sperm movement and life.
  · It is important to note that the prostate gland is often the site of cancerous cell growth in older males.
  Bulbourethral glands (Cowper's glands) are pea-sized glands located just below the prostate gland on either the side of the urethra. These glands also secrete an alkaline substance that helps neutralize the acidic environment of the urethra.
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  Hernia
  · A hernia occurs when part of an organ, usually the intestines, pushes through a membrane or muscle that contains an organ.
  · A common hernia is a inguinal hernia, which occurs in a weak spot near the top of the scrotum.
  · Surgery can correct the problem.
  Prostate Cancer
  · Prostate cancer is a common cancer in older males since the risk of prostate cancer increases with age.
  · It can be effectively treated when detected early; therefore, it is important that males over the age of 40 receive an annual physical to determine the size of the prostate.
  · Cancer of the prostate can be detected with a blood test known as a PSA. If the PSA is high, biopsy of the prostate to check the cancerous cells is the next step.
  Testicular Cancer
  · Testicular cancer is the most common cancer in men ages 15-24.
  · Check for the presence of a hard, painless lump. If the lump is painful, it is most likely a bruise.
  
  The best time to perform the examination is after a warm bath or shower, when the scrotal skin is the most relaxed. (Scrotal skin is on the scrotum, the sac in which the testicles are normally found.)
  Roll each testicle gently between the thumb and fingers of both hands. A normal testicle is smooth, egg-shaped, and somewhat firm to the touch. (Behind each testicle is the epididymis, which carries sperm away from the testicle.)
  If you find any hard lumps or nodules, or if there is any change in the shape, size, or texture of the testicles, consult a physician promptly. These signs may not indicate cancer, but only your physician can make a definite diagnosis.
  The female reproductive system serves four important functions:
  (1) It produces eggs,
  (2) It is the site of fertilization,
  (3) it provides nourishment and protection for the fertilized egg as it develops into a fetus, and further develops into a baby capable of life outside the mother's body, and
  (4) It produces hormones.
  Ovaries
  · The ovaries are the primary female organs.
  · Two almond-shaped glands, approximately one inch long, located within the pelvic cavity.
  · Two functions: To produce the hormones estrogen and progesterone and to produce eggs.
  · The production and maturation of eggs continues during puberty (the eggs are actually produced before she is born).
  · This process is under the control of the two above-mentioned hormones.
  · The release of eggs from the ovaries occurs in a process known as ovulation
  Uterine Tubes
  · The uterine tubes (Fallopian tubes) are four inches long and one-fourth of an inch wide.
  · There are two uterine tubes, one located on each side of the uterus.
  · The uterine tubes are responsible for transporting eggs from the ovaries to the uterus.
  · On the side of the uterine tube that is attached to the ovary, the tube opens and expands into a funnel known as the infundibulum. It has long, finger-like projections known as fimbriae.
  · Movement of the egg within the uterine tube occurs as a result of muscle contractions and the movement of small hairs located within the tube.
  · Fertilization will occur if sperm cells are present while the egg is in the uterine tubes.
  Uterus
  The uterus is an organ located in the pelvis that is shaped like an upside-down pear. The uterus is three inches long and two inches wide. The most upper portion is called the fundus, the middle section is called the body, and the lower third is called the cervix. The wall of the uterus is composed of three layers. The inner lining is the endometrium and is where a fertilized egg implants. If fertilization does not occur while in the uterine tubes, the lining of the uterus is lost in a process known as menstruation, consisting of periods (see section entitled "The Menstrual Cycle"). The second layer is the myometrium, or muscle layer. The muscle contractions help to push the fetus outside during delivery. The outer layer, or perimetrium, provides protection for the uterus.
  Vagina
  The vagina is a four-inch-long muscular tube attached to the cervix and located below the uterus. It leads to the outside of the body. The vagina is very elastic and can stretch many times its normal size. The vagina has four functions: (1) it serves as a receptacle for the erect penis, (2) it is where the sperm is deposited during intercourse, (3) it serves as the birth canal for the delivery of the fetus, and (4) it is an exit for the tissue associated with menstruation. Just inside the vagina are two glands called Bartholin's (vestibular) glands. These glands secrete small amounts of fluid and mucous to lubricate the opening of the vagina prior to sexual intercourse.
  Vulva
  The vulva contains the female external reproductive organs. The labia majora encloses and protects the external reproductive organs. It is composed of skin and fat. The front region of the labia majora is called the mons pubis, which covers the front portion of the pubic bone. The labia minora lies inside of the labia majora. It forms a covering around the clitoris. The clitoris is a small projection at the front end of the vulva. It contains many sensory nerve fibers, as well as erectile tissue.
  Breasts
  There are additional female reproductive structures not located within the pelvic cavity. They are known as the breasts. The breasts are composed of fat to protect the mammary glands, which are specialized to produce milk. Milk provides newborn babies with nourishment as well as antibodies, which protect against disease. A nipple is in the center of each breast and is surrounded by a darkened area of skin called the areola. The nipple is an opening that serves as an exit for the milk. The growth of breasts and mammary glands is under the control of the hormone estrogen and occurs during puberty.
  The Menstrual Cycle
  The brain produces two hormones in the pituitary gland
  The first hormone, follicle-stimulating hormone (FSH) , is responsible for the growth and maturation of eggs in the ovary before they are released into the Fallopian tube.
  While the eggs are maturing, FSH also stimulates the production of another hormone: a group of chemicals known as the estrogens.
  The estrogens have many effects including the building of the uterine lining (endometrium), breast development, and increased fat deposits in the buttocks and thighs.
  In other words, the estrogens prepare the body for possible pregnancy.
  These changes occur during the first thirteen days (the first half) of the menstrual cycle, which is called the preovulatory phase.
  
  · At the midpoint of the cycle, or day fourteen, the pituitary gland increases its production of the second hormone, luteinizing hormone
  
  · At the midpoint of the cycle, or day fourteen, the pituitary gland increases its production of the second hormone, luteinizing hormone (LH). This second hormone allows the mature egg to rupture from the ovary (called ovulation) and enter into the uterine tube. The postovulatory phase has begun. LH also encourages the formation of a "scar" within the ovary. This "scar" is where the egg was located before ovulation and is called the corpus luteum, and it produces the hormone progesterone. Progesterone's role is to increase the blood supply to the endometrium. This is important; if the egg is fertilized by a sperm, it will implant into the uterus where it will stay for the next nine months.
  · If fertilization does not take place, the menses phase begins and the corpus luteum shrinks in size. The levels of progesterone and estrogen drop, and the uterine lining (endometrium) is lost during the monthly blood flow or period. The blood and some of the endometrial cells will exit the body through the vagina. The unfertilized egg will also disintegrate. Since the first day of one's period is so highly visible, it is referred to as the first day, or day one, of the menstrual cycle. The average menstrual cycle is twenty-eight days, but an individual female's cycle may have more or less days.
  PMS (Premenstrual Syndrome)
  PMS is a collection of physical and mental symptoms that can disrupt a woman's life. The symptoms include the following:
  physical discomfort
  swelling of hands and feet
  painful menstruation
  backaches
  fatigue
  irritability
  depression
  breast tenderness
  abdominal bloating and cramping
  constipation or diarrhea
  headaches
  weight gain of three to nine pounds associated with the menstrual flow
  hunger and binges especially for sweet or salty foods
  
  The treatment
  · Medications and lifestyle changes.
  · The lifestyle changes involve dietary changes, exercise, and stress reduction.
  · Nutritional supplements such as vitamin B6 or calcium may be added to the diet.
  · Analgesics, such as ibuprofen, may be given for pain.
  · Sometimes a woman may need antianxiety drugs or antidepression drugs when she is having PMS.
  · She may also need to begin hormone therapy
  Toxic Shock Syndrome (TSS)
  · Toxic Shock Syndrome (TSS) is an infection that can be associated with tampon use during menstruation.
  · Staphylococcus aureus is the bacteria responsible for TSS.
  · The symptoms of toxic shock syndrome include
  1. high fever,
  2. headache,
  3. discharge from the vagina,
  4. diarrhea,
  5. nausea,
  6. vomiting,
  7. severe fatigue,
  8. and a red rash that looks like a sunburn.
  
  · Symptoms may get worse as the infection grows.
  · The major problem with TSS is that it can cause failure of the kidney, heart, and liver.
  · Treatment includes antibiotics and other medications to control the infection.
  · It is important to change tampons regularly to reduce the risk of this infection.
  · It is also suggested that women consider using sanitary napkins instead of tampons while sleeping
  Maintaining the Health of the Female Reproductive System
  Daily care for the female reproductive system revolves around cleanliness. Once the female goes through puberty, there may be a slight vaginal odor, so cleanliness is especially important. Tampons and sanitary napkins are used during a female's period to absorb the menstrual flow. For hygienic purposes and to reduce the risk of infections like toxic shock syndrome, it is recommended that tampons be changed every few hours. Women should be sure to read the package inserts for more detailed information before using a product. Feminine deodorant sprays and douches are not usually necessary and may irritate the delicate vaginal tissues. 197
  Breast Self-Exams
  It is important that females do breast self-examinations (BSE) on a monthly basis (see figure 4-5). It is probably best to do this right after one's period has ended when the breasts are not as sore. Regular inspection of the breasts will help you to know what your normal breast tissue should look like.
  
  Mammograms
  After the age of thirty-five
  This procedure x-rays the breasts and helps identify the presence of abnormalities
  It is estimated that one in every eight women will be diagnosed with breast cancer some time in her life
  Early detection means less invasive surgery as well as less chemotherapy or radiation as follow-up therapy.
  note that men can also be victims of breast cancer, although it is rare.
  Pap Smears
  Starting around the age of 18-20,
  cell-screening test that helps to detect cancer of the cervix.
  The cervix is the lower part of the uterus.
  Cervical cancer eventually kills one-third of women who are diagnosed with it.
  Remember, the key to fighting and winning the war with cancer is early detection and early treatment.
  Five pairs of analogous organs are discussed below:
  Male testes are similar to female ovaries. Both ovaries and testes produce hormones. The testes produce the hormone testosterone, which is responsible for male sex characteristics. The ovaries produce the hormones estrogen and progesterone, which are responsible for female sex characteristics and the growth and development of the uterus lining. Also, both organs produce gametes: the testes produce sperm while the ovaries produce eggs.
  The male ductus deferens is similar to the female uterine tubes. The ductus deferens is composed of three layers lined with cilia (small hairs) and serves as a passageway for sperm. The uterine tubes are also composed of three layers lined with cilia. The uterine tubes serve as a passageway for the eggs and sperm and is the site of fertilization.
  The male scrotum is similar to the female labia majora. Both function to enclose and protect external reproductive organs.
  The male penis is similar to the female clitoris. The penis and the clitoris contain many sensory nerve fibers and erectile tissue.
  The male bulbourethral glands are similar to the female vestibular glands. The secretion of the bulbourethral glands (Cowper's glands) neutralizes the acid of the urethra and lubricates the tip of the penis prior to intercourse. The vestibular glands (Bartholin's glands) lubricate the opening to the vagina prior to intercourse.
  Factors that affect the aging process include genetics, living conditions, nutritional choices over the years, and socioeconomic status.
  Females
  As the female reproductive system ages, there is a decrease in estrogen and progesterone, which causes the vaginal walls and supporting tissues of the uterus to thin.
  The breasts sag as the fat is redistributed.
  As a woman approaches fifty, her ovaries gradually stop producing estrogen.
  This causes a set of symptoms that are collectively known as menopause.
  Symptoms of menopause include hot flashes in the face and upper chest, headaches, dizziness, heart beat irregularities, and joint pain.
  The loss of estrogen may predispose a woman to osteoporosis, which is the loss of bone calcium and mass.
  Some women also become moody, depressed, tired, irritable, or forgetful.
  Males
  aging tends to shrink the size of the testes;
  this shrinking reduces testosterone and sperm production.
  Physical changes can cause mental or emotional changes sometimes called a "mid-life crises."
  Many men and women alike may experience this.
  Men, just like women, usually take time to reassess their lives, set new goals, and re-evaluate priorities.
  
  produces part of the fluid portion of the semen; neutralizes the acid urethra
  the muscular sac-like structure that holds the testes away from the body
  the male sex hormone that helps in male sex characteristics as well as muscle and bone development
  the male reproductive organ that helps to transfer sperm into the woman’s body
  the male reproductive cells that contain the man’s genetic information for offspring
  the long tube-like passageway which connects the epididymis to the ejaculatory duct; transports sperm as they leave the body
  the foreskin which covers the tip of the penis
  the tube that runs through the center of the penis; it can transport urine or sperm (semen) but not at the same time
  the male organ which produces sperm and testosterone
  the coiled structures located on top of the testes where sperm matures
  the donut-shaped gland at the top of the urethra that produces some of the fluid in the semen
  
  
  How Does Fertilization Occur?
  · After sperm cells are deposited in the vagina through sexual intercourse, they travel upward to the egg by means of their tails.
  · Sperm movement is also assisted by muscle contractions of the uterus and uterine tubes (fallopian).
  · After the egg bursts from the ovary, it is swept into the uterine tubes by the tiny fimbriae.
  · Fertilization, or conception, takes place within the uterine tubes.
  · When the sperm reaches the egg, it penetrates the tough membrane of the egg by enzymes found within the sperm.
  · The nuclei of the egg and sperm fuse together, producing a cell known as a zygote.
  · A zygote is the first fertilized cell.
  · Once the zygote is formed, cleavage begins.
  · Cleavage is a process of cell division in which the next cells are smaller than the ones before.
  · The zygote divides into two, then four, eight, and finally sixteen cells.
  · The mass of sixteen cells is known as a morula, and it continues passage through the uterine tube.
  · It is transported down to the uterus by the uterine tube's muscle contractions and the sweeping motion of the fimbriae.
  · Three days have passed by now.
  · The morula enters the uterus and remains free-floating within the uterus for another three days.
  · During this time the mass of cells becomes hollow, which is known as a blastocyst.
  · The blastocyst implants in the lining of the uterus. This occurs approximately seven days after fertilization.
  · Once implantation has occurred, the cluster of cells is called an embryo.
  · The embryo is about the size of a pinhead.
  ·
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  Role of Genetics
  · Located within the center nuclei of both eggs and sperm is genetic material, or DNA.
  · DNA is found in sticky, stringy material known as chromosomes.
  · Each cell in the human body has forty-six chromosomes—except eggs and sperm, which each have twenty-three chromosomes.
  · When fertilization occurs, the nuclei of an egg and sperm fuse together, forming a zygote with forty-six chromosomes.
  · The DNA controls all aspects of growth and development in the zygote by controlling what chemicals its cells make, which leads to what types of cells they become.
  · Genetics is the study of how information in the form of DNA is passed from parent to offspring.
  · DNA is subdivided into specific units called genes.
  · These genes control specific traits such as height, hair color, eye color, and blood type. They may even control the offspring's susceptibility to some diseases such as cancer.
  · Some genes are dominant, which means the traits they control will be present in the offspring even if the offspring only received that dominate gene from one parent.
  · Other genes are recessive. The traits these genes control only show up if the offspring receives that recessive gene from both parents.
  · There may also be genetic mistakes when DNA makes copies of itself to form new cells.
  · These mistakes are known as mutations.
  · A mutation may involve only one small section of the DNA on a chromosome, or it may impact the whole chromosome.
  · Sometimes these mutations involve a tiny piece of the gene called a nucleotide, which can be in an incorrect order.
  · This may cause problems for the body because it cannot make its needed proteins. This occurs in disorders such as sickle-cell anemia.
  · Sickle-cell anemia is a genetic blood disorder in which the red blood cells are abnormally shaped like a sickle instead of having nice, round, smooth edges.
  · These blood cells can stick together in the blood vessels and cause pain and other problems.
  · Other mutations involve entire extra or missing chromosomes. Down's syndrome results in cells that have forty-seven chromosomes instead of the usual forty-six. People with Down's syndrome suffer from mental challenges and physical defects and have a distinct facial appearance. While people with Down's syndrome have one extra chromosome, those with Turner's syndrome are missing one. Turner's syndrome occurs when a female embryo has only one sex-linked chromosome instead of two (see next paragraph for more information on sex-linked chromosomes). This reduces the female's chromosome number from forty-six to forty-five. Females with Turner's syndrome are shorter than usual and have a webbed neck. They are also infertile (cannot produce offspring).
  · On another hand, some disorders may affect genes only located on the sex chromosomes—which are XX for females and XY for males. Examples of these sex-linked disorders are color-blindness and hemophilia. Color blindness occurs when the nerves in the eye carry a genetic disorder, preventing them from seeing some colors—like red and green, for example.
  · Hemophilia is a genetic disorder that does not allow the blood to clot properly.
  · Both of these disorders are located on the X chromosome.
  · Note that if there is another X chromosome present that does not have the disorder, the disorder will not show up.
  · Since males only have one X chromosome, they show these disorders more often than females.
  
  NEXT IS CHAPTER 4 PG. 6!

• CHAPTER 4 HEALTH NOTES!
  There are physical changes like growth spurts and weight gain.
  Your body's reproductive organs start to develop and mature as you near adulthood.
  
  MALE:
  The male reproductive system serves two important functions:
  (1) it produces sperm
  (2) it produces hormones that assist in the growth and development of young men.
  
  The internal male organs are the testes, epididymis, vas deferens, ejaculatory duct, prostate gland, seminal vesicles, and bulbourethral (Cowper's) glands.
  The external penis surrounds the urethra, which transports both urine and sperm (but not at the same time).
  The scrotum, a sac-like structure that holds the testes away from the body, is also an external structure (see figure 4-1).
  
  
  Testes
  · The testes are the male sex glands responsible for the production of sperm cells and the male hormone testosterone.
  · They are inclosed by the scrotum. The scrotum is a skin outpouching of the abdomen consisting of loose skin and superficial fascia. It functions to enclose and protect the testes and maintains a constant temperature about 3 degrees Fahrenheit below normal body temperature for optimal sperm production.
  ·
  Sperm
  · The process of sperm production is called spermatogenesis.
  · Takes about seventy-four days for human males to create sperm through spermatogenesis.
  · Seminiferous tubules are tightly coiled tubules in the testes where spermatogenesis occurs. In these tubules, immature sperm cells, or spermatogonia, grow into fully-matured sperm cells called a spermatozoon.
  · Another type of cell called sertoli cells provide a barrier for the developing sperm cells to ensure the maturation process takes place correctly.
  · Spermatozoa (mature sperm cells) mature at a rate of about 300 million per day.
  · Once ejaculated through the penis, they have a life expectancy of about forty-eight hours.
  Each spermatozoon (commonly called sperm) has a head, midpiece, and tail.
  · The head is the portion of the sperm that contains the genetic material (DNA) for a potential offspring.
  · The surface of the head is made from acrosome, a dense, granular material that contains enzymes to help the sperm penetrate the egg cell.
  · The midpiece is the portion of the sperm that has numerous mitochondria, where energy for the movement of the sperm is made.
  · The tail propels the sperm forward.
  Testosterone and Puberty
  · the principle male hormone
  · controls growth and development,
  · maintains the male sex organs,
  · causes hairline recession,
  · stimulates bone growth,
  · stimulates anabolism (the phase of metabolism when the nutrients and other substances are broken down and used by the body) of protein,
  · and helps in muscular development.
  · Testosterone is also responsible for the closure of epiphyseal plates
  · which are the growth plates in bones
  · It influences sexual behavior and causes the final maturation of sperm.
  
  Puberty begins at about age ten or eleven and is completed around age fifteen to seventeen. During puberty (a term which literally means "marriageable age"), secondary male sex characteristics are developed.
  Testosterone aids in the development of pubic, axillary, and chest hair; facial hair growth; and the deepening of the voice and enlargement of the voice box.
  Potential for sexual reproduction is reached.
  Movement from the Testes to Outside the Body
  1. From the highly coiled seminiferous tubules of the testes, the sperm move through a series of straight tubules to a network of ducts in the testes called the rete testis.
  2. After the sperm leave the testes, they continue their journey to the epididymis—a comma-shaped organ that lies along the posterior border of the testes.
  · The epididymis consists mostly of a tightly coiled tube called the ductus epididymis, which measures about twenty feet in length when stretched out!
  · This is the site of further sperm maturation (sperm requires about ten to fourteen additional days here to completely mature).
  3. Sperm may remain in the ductus epididymis for up to four weeks, after which they are either expelled or reabsorbed by the body.
  4. The ductus deferens (or vas deferens) is the next location for the sperm.
  · This organ is a long tube (eighteen inches) that serves as the passageway for sperm from the epididymis to the urethra. Near the end of the vas deferens are the ejaculatory ducts—tubes just behind the urinary bladder formed by the union of the tubes from the seminal vesicle and the vas deferens.
  5. The ejaculatory ducts eject sperm into the urethra just prior to ejaculation.
  The urethra is the end tube for both the reproductive and urinary systems. It is a narrow tube that spans from inside the body to the end of the penis. The urethra serves as the passageway for urine or spermatozoa to leave the body and enter the external environment. The urethra measures about eight inches in length, throughout which there are four portions:
  Prostatic urethra—the portion of the urethra that passes through the prostate gland
  Membranous urethra—the middle portion of the urethra
  Spongy urethra—the portion of the urethra contained in the penis
  External urethral orifice—external opening of the urethra
  The penis is the portion of the male anatomy used to introduce the sperm into the female vagina during intercourse. It is cylindrical in shape and consists of the root, body, and glands.
  The root is the portion of the penis that is attached to the pubic area, or the lower abdomen. The body is composed of three cylindrical masses of tissue each bound by fibrous tissue. Under the influence of sexual stimulation (visual, tactile, auditory, olfactory, and imaginative), the arteries supplying the penis dilate (or open up), large quantities of blood enter the vessels, and an erection occurs. The glans penis is the slightly enlarged end, or tip, of the penis that is covered by loose-fitting skin called the foreskin or prepuce. The foreskin is removed during a surgical procedure called a circumcision.
  · Semen, or seminal fluid, is a mixture of sperm with the secretions of the accessory male sex glands, which consist of the seminal vesicles, prostate gland, and bulbourethral glands (Cowper's gland).
  · The average volume of semen for ejaculation is 2.5 to 5 milliliters, and there are about 50 to 150 million sperm per milliliter of semen.
  · If semen contains less than 20 million sperm per milliliter, the male is considered infertile.
  · Seminal vesicles—convoluted pouch-like structures lying at the back of the urinary bladder at the base—secrete an alkaline, thick fluid rich in fructose, a carbohydrate used as an energy source for the sperm. ________This fluid makes up about 60 percent of the volume of the semen, and the alkaline nature of this fluid allows the sperm to survive in the acidic female reproductive tract.
  · Prostate gland is a single, donut-shaped gland about the size of a chestnut located below the urinary bladder and surrounding the urethra.
  · It secretes a slightly acidic fluid rich in citric acid, prostatic acid phosphates, and prostaglandins.
  · It makes up about 13 percent to 33 percent of the semen.
  · The chemicals found in the semen help to contribute to sperm movement and life.
  · It is important to note that the prostate gland is often the site of cancerous cell growth in older males.
  Bulbourethral glands (Cowper's glands) are pea-sized glands located just below the prostate gland on either the side of the urethra. These glands also secrete an alkaline substance that helps neutralize the acidic environment of the urethra.
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  Hernia
  · A hernia occurs when part of an organ, usually the intestines, pushes through a membrane or muscle that contains an organ.
  · A common hernia is a inguinal hernia, which occurs in a weak spot near the top of the scrotum.
  · Surgery can correct the problem.
  Prostate Cancer
  · Prostate cancer is a common cancer in older males since the risk of prostate cancer increases with age.
  · It can be effectively treated when detected early; therefore, it is important that males over the age of 40 receive an annual physical to determine the size of the prostate.
  · Cancer of the prostate can be detected with a blood test known as a PSA. If the PSA is high, biopsy of the prostate to check the cancerous cells is the next step.
  Testicular Cancer
  · Testicular cancer is the most common cancer in men ages 15-24.
  · Check for the presence of a hard, painless lump. If the lump is painful, it is most likely a bruise.
  
  The best time to perform the examination is after a warm bath or shower, when the scrotal skin is the most relaxed. (Scrotal skin is on the scrotum, the sac in which the testicles are normally found.)
  Roll each testicle gently between the thumb and fingers of both hands. A normal testicle is smooth, egg-shaped, and somewhat firm to the touch. (Behind each testicle is the epididymis, which carries sperm away from the testicle.)
  If you find any hard lumps or nodules, or if there is any change in the shape, size, or texture of the testicles, consult a physician promptly. These signs may not indicate cancer, but only your physician can make a definite diagnosis.
  The female reproductive system serves four important functions:
  (1) It produces eggs,
  (2) It is the site of fertilization,
  (3) it provides nourishment and protection for the fertilized egg as it develops into a fetus, and further develops into a baby capable of life outside the mother's body, and
  (4) It produces hormones.
  Ovaries
  · The ovaries are the primary female organs.
  · Two almond-shaped glands, approximately one inch long, located within the pelvic cavity.
  · Two functions: To produce the hormones estrogen and progesterone and to produce eggs.
  · The production and maturation of eggs continues during puberty (the eggs are actually produced before she is born).
  · This process is under the control of the two above-mentioned hormones.
  · The release of eggs from the ovaries occurs in a process known as ovulation
  Uterine Tubes
  · The uterine tubes (Fallopian tubes) are four inches long and one-fourth of an inch wide.
  · There are two uterine tubes, one located on each side of the uterus.
  · The uterine tubes are responsible for transporting eggs from the ovaries to the uterus.
  · On the side of the uterine tube that is attached to the ovary, the tube opens and expands into a funnel known as the infundibulum. It has long, finger-like projections known as fimbriae.
  · Movement of the egg within the uterine tube occurs as a result of muscle contractions and the movement of small hairs located within the tube.
  · Fertilization will occur if sperm cells are present while the egg is in the uterine tubes.
  Uterus
  The uterus is an organ located in the pelvis that is shaped like an upside-down pear. The uterus is three inches long and two inches wide. The most upper portion is called the fundus, the middle section is called the body, and the lower third is called the cervix. The wall of the uterus is composed of three layers. The inner lining is the endometrium and is where a fertilized egg implants. If fertilization does not occur while in the uterine tubes, the lining of the uterus is lost in a process known as menstruation, consisting of periods (see section entitled "The Menstrual Cycle"). The second layer is the myometrium, or muscle layer. The muscle contractions help to push the fetus outside during delivery. The outer layer, or perimetrium, provides protection for the uterus.
  Vagina
  The vagina is a four-inch-long muscular tube attached to the cervix and located below the uterus. It leads to the outside of the body. The vagina is very elastic and can stretch many times its normal size. The vagina has four functions: (1) it serves as a receptacle for the erect penis, (2) it is where the sperm is deposited during intercourse, (3) it serves as the birth canal for the delivery of the fetus, and (4) it is an exit for the tissue associated with menstruation. Just inside the vagina are two glands called Bartholin's (vestibular) glands. These glands secrete small amounts of fluid and mucous to lubricate the opening of the vagina prior to sexual intercourse.
  Vulva
  The vulva contains the female external reproductive organs. The labia majora encloses and protects the external reproductive organs. It is composed of skin and fat. The front region of the labia majora is called the mons pubis, which covers the front portion of the pubic bone. The labia minora lies inside of the labia majora. It forms a covering around the clitoris. The clitoris is a small projection at the front end of the vulva. It contains many sensory nerve fibers, as well as erectile tissue.
  Breasts
  There are additional female reproductive structures not located within the pelvic cavity. They are known as the breasts. The breasts are composed of fat to protect the mammary glands, which are specialized to produce milk. Milk provides newborn babies with nourishment as well as antibodies, which protect against disease. A nipple is in the center of each breast and is surrounded by a darkened area of skin called the areola. The nipple is an opening that serves as an exit for the milk. The growth of breasts and mammary glands is under the control of the hormone estrogen and occurs during puberty.
  The Menstrual Cycle
  The brain produces two hormones in the pituitary gland
  The first hormone, follicle-stimulating hormone (FSH) , is responsible for the growth and maturation of eggs in the ovary before they are released into the Fallopian tube.
  While the eggs are maturing, FSH also stimulates the production of another hormone: a group of chemicals known as the estrogens.
  The estrogens have many effects including the building of the uterine lining (endometrium), breast development, and increased fat deposits in the buttocks and thighs.
  In other words, the estrogens prepare the body for possible pregnancy.
  These changes occur during the first thirteen days (the first half) of the menstrual cycle, which is called the preovulatory phase.
  
  · At the midpoint of the cycle, or day fourteen, the pituitary gland increases its production of the second hormone, luteinizing hormone
  
  · At the midpoint of the cycle, or day fourteen, the pituitary gland increases its production of the second hormone, luteinizing hormone (LH). This second hormone allows the mature egg to rupture from the ovary (called ovulation) and enter into the uterine tube. The postovulatory phase has begun. LH also encourages the formation of a "scar" within the ovary. This "scar" is where the egg was located before ovulation and is called the corpus luteum, and it produces the hormone progesterone. Progesterone's role is to increase the blood supply to the endometrium. This is important; if the egg is fertilized by a sperm, it will implant into the uterus where it will stay for the next nine months.
  · If fertilization does not take place, the menses phase begins and the corpus luteum shrinks in size. The levels of progesterone and estrogen drop, and the uterine lining (endometrium) is lost during the monthly blood flow or period. The blood and some of the endometrial cells will exit the body through the vagina. The unfertilized egg will also disintegrate. Since the first day of one's period is so highly visible, it is referred to as the first day, or day one, of the menstrual cycle. The average menstrual cycle is twenty-eight days, but an individual female's cycle may have more or less days.
  PMS (Premenstrual Syndrome)
  PMS is a collection of physical and mental symptoms that can disrupt a woman's life. The symptoms include the following:
  physical discomfort
  swelling of hands and feet
  painful menstruation
  backaches
  fatigue
  irritability
  depression
  breast tenderness
  abdominal bloating and cramping
  constipation or diarrhea
  headaches
  weight gain of three to nine pounds associated with the menstrual flow
  hunger and binges especially for sweet or salty foods
  
  The treatment
  · Medications and lifestyle changes.
  · The lifestyle changes involve dietary changes, exercise, and stress reduction.
  · Nutritional supplements such as vitamin B6 or calcium may be added to the diet.
  · Analgesics, such as ibuprofen, may be given for pain.
  · Sometimes a woman may need antianxiety drugs or antidepression drugs when she is having PMS.
  · She may also need to begin hormone therapy
  Toxic Shock Syndrome (TSS)
  · Toxic Shock Syndrome (TSS) is an infection that can be associated with tampon use during menstruation.
  · Staphylococcus aureus is the bacteria responsible for TSS.
  · The symptoms of toxic shock syndrome include
  1. high fever,
  2. headache,
  3. discharge from the vagina,
  4. diarrhea,
  5. nausea,
  6. vomiting,
  7. severe fatigue,
  8. and a red rash that looks like a sunburn.
  
  · Symptoms may get worse as the infection grows.
  · The major problem with TSS is that it can cause failure of the kidney, heart, and liver.
  · Treatment includes antibiotics and other medications to control the infection.
  · It is important to change tampons regularly to reduce the risk of this infection.
  · It is also suggested that women consider using sanitary napkins instead of tampons while sleeping
  Maintaining the Health of the Female Reproductive System
  Daily care for the female reproductive system revolves around cleanliness. Once the female goes through puberty, there may be a slight vaginal odor, so cleanliness is especially important. Tampons and sanitary napkins are used during a female's period to absorb the menstrual flow. For hygienic purposes and to reduce the risk of infections like toxic shock syndrome, it is recommended that tampons be changed every few hours. Women should be sure to read the package inserts for more detailed information before using a product. Feminine deodorant sprays and douches are not usually necessary and may irritate the delicate vaginal tissues. 197
  Breast Self-Exams
  It is important that females do breast self-examinations (BSE) on a monthly basis (see figure 4-5). It is probably best to do this right after one's period has ended when the breasts are not as sore. Regular inspection of the breasts will help you to know what your normal breast tissue should look like.
  
  Mammograms
  After the age of thirty-five
  This procedure x-rays the breasts and helps identify the presence of abnormalities
  It is estimated that one in every eight women will be diagnosed with breast cancer some time in her life
  Early detection means less invasive surgery as well as less chemotherapy or radiation as follow-up therapy.
  note that men can also be victims of breast cancer, although it is rare.
  Pap Smears
  Starting around the age of 18-20,
  cell-screening test that helps to detect cancer of the cervix.
  The cervix is the lower part of the uterus.
  Cervical cancer eventually kills one-third of women who are diagnosed with it.
  Remember, the key to fighting and winning the war with cancer is early detection and early treatment.
  Five pairs of analogous organs are discussed below:
  Male testes are similar to female ovaries. Both ovaries and testes produce hormones. The testes produce the hormone testosterone, which is responsible for male sex characteristics. The ovaries produce the hormones estrogen and progesterone, which are responsible for female sex characteristics and the growth and development of the uterus lining. Also, both organs produce gametes: the testes produce sperm while the ovaries produce eggs.
  The male ductus deferens is similar to the female uterine tubes. The ductus deferens is composed of three layers lined with cilia (small hairs) and serves as a passageway for sperm. The uterine tubes are also composed of three layers lined with cilia. The uterine tubes serve as a passageway for the eggs and sperm and is the site of fertilization.
  The male scrotum is similar to the female labia majora. Both function to enclose and protect external reproductive organs.
  The male penis is similar to the female clitoris. The penis and the clitoris contain many sensory nerve fibers and erectile tissue.
  The male bulbourethral glands are similar to the female vestibular glands. The secretion of the bulbourethral glands (Cowper's glands) neutralizes the acid of the urethra and lubricates the tip of the penis prior to intercourse. The vestibular glands (Bartholin's glands) lubricate the opening to the vagina prior to intercourse.
  Factors that affect the aging process include genetics, living conditions, nutritional choices over the years, and socioeconomic status.
  Females
  As the female reproductive system ages, there is a decrease in estrogen and progesterone, which causes the vaginal walls and supporting tissues of the uterus to thin.
  The breasts sag as the fat is redistributed.
  As a woman approaches fifty, her ovaries gradually stop producing estrogen.
  This causes a set of symptoms that are collectively known as menopause.
  Symptoms of menopause include hot flashes in the face and upper chest, headaches, dizziness, heart beat irregularities, and joint pain.
  The loss of estrogen may predispose a woman to osteoporosis, which is the loss of bone calcium and mass.
  Some women also become moody, depressed, tired, irritable, or forgetful.
  Males
  aging tends to shrink the size of the testes;
  this shrinking reduces testosterone and sperm production.
  Physical changes can cause mental or emotional changes sometimes called a "mid-life crises."
  Many men and women alike may experience this.
  Men, just like women, usually take time to reassess their lives, set new goals, and re-evaluate priorities.
  
  produces part of the fluid portion of the semen; neutralizes the acid urethra
  the muscular sac-like structure that holds the testes away from the body
  the male sex hormone that helps in male sex characteristics as well as muscle and bone development
  the male reproductive organ that helps to transfer sperm into the woman’s body
  the male reproductive cells that contain the man’s genetic information for offspring
  the long tube-like passageway which connects the epididymis to the ejaculatory duct; transports sperm as they leave the body
  the foreskin which covers the tip of the penis
  the tube that runs through the center of the penis; it can transport urine or sperm (semen) but not at the same time
  the male organ which produces sperm and testosterone
  the coiled structures located on top of the testes where sperm matures
  the donut-shaped gland at the top of the urethra that produces some of the fluid in the semen
  
  
  How Does Fertilization Occur?
  · After sperm cells are deposited in the vagina through sexual intercourse, they travel upward to the egg by means of their tails.
  · Sperm movement is also assisted by muscle contractions of the uterus and uterine tubes (fallopian).
  · After the egg bursts from the ovary, it is swept into the uterine tubes by the tiny fimbriae.
  · Fertilization, or conception, takes place within the uterine tubes.
  · When the sperm reaches the egg, it penetrates the tough membrane of the egg by enzymes found within the sperm.
  · The nuclei of the egg and sperm fuse together, producing a cell known as a zygote.
  · A zygote is the first fertilized cell.
  · Once the zygote is formed, cleavage begins.
  · Cleavage is a process of cell division in which the next cells are smaller than the ones before.
  · The zygote divides into two, then four, eight, and finally sixteen cells.
  · The mass of sixteen cells is known as a morula, and it continues passage through the uterine tube.
  · It is transported down to the uterus by the uterine tube's muscle contractions and the sweeping motion of the fimbriae.
  · Three days have passed by now.
  · The morula enters the uterus and remains free-floating within the uterus for another three days.
  · During this time the mass of cells becomes hollow, which is known as a blastocyst.
  · The blastocyst implants in the lining of the uterus. This occurs approximately seven days after fertilization.
  · Once implantation has occurred, the cluster of cells is called an embryo.
  · The embryo is about the size of a pinhead.
  ·
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  Role of Genetics
  · Located within the center nuclei of both eggs and sperm is genetic material, or DNA.
  · DNA is found in sticky, stringy material known as chromosomes.
  · Each cell in the human body has forty-six chromosomes—except eggs and sperm, which each have twenty-three chromosomes.
  · When fertilization occurs, the nuclei of an egg and sperm fuse together, forming a zygote with forty-six chromosomes.
  · The DNA controls all aspects of growth and development in the zygote by controlling what chemicals its cells make, which leads to what types of cells they become.
  · Genetics is the study of how information in the form of DNA is passed from parent to offspring.
  · DNA is subdivided into specific units called genes.
  · These genes control specific traits such as height, hair color, eye color, and blood type. They may even control the offspring's susceptibility to some diseases such as cancer.
  · Some genes are dominant, which means the traits they control will be present in the offspring even if the offspring only received that dominate gene from one parent.
  · Other genes are recessive. The traits these genes control only show up if the offspring receives that recessive gene from both parents.
  · There may also be genetic mistakes when DNA makes copies of itself to form new cells.
  · These mistakes are known as mutations.
  · A mutation may involve only one small section of the DNA on a chromosome, or it may impact the whole chromosome.
  · Sometimes these mutations involve a tiny piece of the gene called a nucleotide, which can be in an incorrect order.
  · This may cause problems for the body because it cannot make its needed proteins. This occurs in disorders such as sickle-cell anemia.
  · Sickle-cell anemia is a genetic blood disorder in which the red blood cells are abnormally shaped like a sickle instead of having nice, round, smooth edges.
  · These blood cells can stick together in the blood vessels and cause pain and other problems.
  · Other mutations involve entire extra or missing chromosomes. Down's syndrome results in cells that have forty-seven chromosomes instead of the usual forty-six. People with Down's syndrome suffer from mental challenges and physical defects and have a distinct facial appearance. While people with Down's syndrome have one extra chromosome, those with Turner's syndrome are missing one. Turner's syndrome occurs when a female embryo has only one sex-linked chromosome instead of two (see next paragraph for more information on sex-linked chromosomes). This reduces the female's chromosome number from forty-six to forty-five. Females with Turner's syndrome are shorter than usual and have a webbed neck. They are also infertile (cannot produce offspring).
  · On another hand, some disorders may affect genes only located on the sex chromosomes—which are XX for females and XY for males. Examples of these sex-linked disorders are color-blindness and hemophilia. Color blindness occurs when the nerves in the eye carry a genetic disorder, preventing them from seeing some colors—like red and green, for example.
  · Hemophilia is a genetic disorder that does not allow the blood to clot properly.
  · Both of these disorders are located on the X chromosome.
  · Note that if there is another X chromosome present that does not have the disorder, the disorder will not show up.
  · Since males only have one X chromosome, they show these disorders more often than females.
  
  NEXT IS CHAPTER 4 PG. 6!