CHD3243 Ch. 4: Body Issues

What are the four difficulties that adolescents might experience with their menstrual periods? What symptoms might adolescents experience during the premenstrual period?

1. *Dysmenorrhea* is difficult or painful menstruation: menstrual cramps, abdominal pain, or other symptoms. 2. *Menhorrhagia* is excessive bleeding. • These conditions may be caused by an excess of *prostaglandins*, hormones that cause smooth muscle contractions. They can be helped by *antiprostaglandins*, drugs that destroy prostaglandins (e.g. ibuprofen). 3. *Amenorrhea* is the absence of flow; this may be due to a variety of factors (e.g. rough exercise, climate change). 4. *Metrorrhagia* is the bleeding from the uterus at times other than during menstruation; this is not common. ✭ Adolescents may also experience mood swings; retain fluid; gain weight; have an increased appetite; or feel their breasts swell or ache during the premenstrual period.

What are the determinants of height? What is the *secular trend*?

1. *Heredity* is an important determinant of height; for example, tall parents have tall children. 2. *Nutrition* is the most important environmental determinant of height. 3. The *age at sexual maturation* also affects the total height achieved; early maturers tend to be a little shorter as adults than those who are late maturers. • The *secular trend* is that children today experience a growth spurt earlier, grow faster, & attain a greater height than children in the past. However, this trend has recently tapered off in the U.S. & other developed countries.

What are the 3 skin glands that can cause problems for adolescents? How do they cause problems? W

1. *Merocrine glands* (sweat glands that are distributed over the entire body). 2. *Apocrine glands* (sweat glands are located in the armpit, mammary, genital, & anal regions). 3. *Sebaceous glands* (skin glands are that produce oil).

What are the 5 stages of breast development?

1. *Prepubertal Stage* - The breasts are flat. 2. *Bud Stage* - Two years before menarche, the nipple & areola become enlarged, elevated, & pigmented. 3. *Primary Stage* - Fat around the nipple & areola cause the areola to project in a mound above the chest wall. 4. *Secondary or Mature Stage* - After menarche, the mammary gland tissue develops & produces larger, rounder breasts. The areola recedes & is incorporated into the breast itself so that only the nipple protrudes. 5. *Adult Stage* - Development is complete.

Which 6 factors influence the health decisions of adolescents?

1. *Their knowledge of the health consequences of particular behaviors*. This knowledge is based on what parents, peers, doctors, teachers, & the media have taught them. 2. *Their ability to judge risks & make rational decisions*. Adolescents' ability to think abstractly, consider long-term consequences, & weigh personal risk is not fully developed. 3. *Their parents' behavior*. If parents don't care about their health, then adolescents may also be careless. In addition, parents who monitor their adolescents give them less opportunity to engage in dangerous behaviors. 4. *The resources available to teens & their families*. Some families have the desire to lead a healthy lifestyle but not the means. For example, some families have no choice but to live in a polluted or violent neighborhood. 5. *Peer pressure*. Peers can convince one another to engage in negative behaviors or positive behaviors. 6. *Societal values*. The images that adolescents see in the media often encourage less-than-ideal health behaviors.

What is the *pituitary gland*? Which hormones does it produce?

The *pituitary gland* is located at the base of the brain. It has 3 lobes: anterior, intermediary, & posterior. The anterior lobe is known as the "master gland of the body" because it produces several hormones: • *Gonadotrophic hormones* influence the *gonads* or *sex glands* (testes & ovaries): - *Follicle-stimulating (FSH)* stimulates the growth of eggs in the ovaries & sperm in the testes. - In the male, *luteinizing hormone (LH)* controls the production & release of male sex hormones by the testes. In the female, LH works with FSH to control the production & release of female sex hormones by the ovary. - *Human growth hormone (HGH)* affects the growth & shaping of the skeleton.

How long is the menstrual cycle? What are the four phases?

The menstrual cycle may vary in length from 20-45 days, averaging about 28 days. It has four phases: 1. *The Menstrual Phase* begins with the first day of menstrual bleeding. • Estrogen, progesterone, FSH, & LH levels are low, which signals the hypothalamus to produce GnRH. • GnRH, in turn, stimulates the pituitary to begin producing FSH. 2. *The Follicular Phase* begins just after menstruation & continues until an ovum matures. • FSH stimulates the growth of an ovum & the secretion of estrogen. • The high estrogen levels result in a thickening of the endometrium to receive a fertilized ovum. • When estrogen levels peak, the hypothalamus directs the pituitary to reduce levels of FSH & to secrete LH. 3. *The Ovulatory Phase* begins 14 days before the beginning of the next menstrual period. • The secretion of LH results in ovulation, in which an ovum erupts from its follicle & enters the fallopian tube. 4. *The Luteal Phase* begins after ovulation & continues until the next menstrual period • The secretion of LH also stimulates the empty follicle to develop into the corpus luteum. • The corpus luteum secretes progesterone, which causes the pituitary to stop producing LH. • Without LH, the corpus luteum degenerates & progesterone declines. • Estrogen, progesterone, FSH, & LH levels are low again, which triggers menstruation; the cycle begins anew.

Describe the sex hormones secreted by the testes.

• *Androgens* are a group of male sex hormones. • *Testosterone* is an androgen that stimulates the development of masculine secondary sexual characteristics & the development of male sex hormones.

What are the 3 body types?

• *Ectomorphs* have a tall, slender body build. • *Endomorphs* have a short, heavy body build. • *Mesomorphs* have a medium, athletic body build. ✭ Most people are a mixture rather than a pure type.

Describe the sex hormones secreted by the ovaries.

• *Estrogens* are a group of female sex hormones that (1) stimulate the development of secondary sexual characteristics, (2) regulate the size & function of the uterus & the vagina, and (3) interact with the pituitary to control the production of various pituitary hormones. • *Progesterone* is produced by a yellow cell mass called the corpus luteum. Progesterone is a sex hormone that (1) controls the length of the menstrual cycle from ovulation until the next menstruation, and (2) prepares the uterus for pregnancy & maintains pregnancy.

What are the interpersonal contributors to being overweight?

• *Family Contributors* - Parents greatly influence what foods their children eat & how much they exercise. For example, parents can prepare healthy meals or take walks & play sports with their children. • *Peer Contributors* - Peers help set behavioral norms; for example, adolescents with friends that participate in sports are more likely to do so. • *Environmental Influences* • Schools - School policies determine what adolescents eat during these hours. In addition, school policies can promotes students' physical activity levels (e.g. ensuring that children enroll in P.E. classes). • Community - Communities can encourage physical activity by providing parks, recreational centers, etc. • *Broader Social Influences* - Today, food is more available; we can purchase food that is ready for consumption; and restaurants' portion sizes have increased enormously. In addition, adolescents spend more time in front of the TV & computer and have become more dependent on automobiles for transport.

What are the personal contributors to being overweight?

• *Genetic Contributors to Obesity* - There is a strong link between genes & body weight. • *Motivation to Eat* - Obese adolescents may eat for different reasons than their peers (e.g. obese girls are more likely to eat when they're unhappy & obese boys are more likely to eat when they're not hungry). • *Eating Patterns* - Overweight adolescents frequently try to control their eating (e.g. they may skip breakfast, have a light lunch, & then binge at night). Others may frequently snack, even when not hungry. Finally, some eat rapidly & so consume more food than normal. • *Food Preferences* - Overweight adolescents may choose more high-calorie foods & eat more in fast food restaurants than their peers. The increase in average adolescent weight can be attributed to an increased consumption of fast food. • *Lack of Exercise* - As discussed, adolescents have low levels of physical activity. However, exercising both burns calories while you're doing it & increases the body's metabolic rate for a period of time after you've finished.

What are *secondary sexual characteristics*?

• *Secondary sexual characteristics* are features not related to reproduction that differentiate male & female bodies.

When do boys experience *semenarche*? What are *nocturnal emissions*?

• *Semenarche* is a boy's first ejaculation. Most boys begin to ejaculate sometime before they turn 13. • Most males experience nocturnal emissions or "wet dreams".

What are health problems of Third World adolescents? Which stem from poverty & political instability, and which stem from Westernization & cultural change?

• *Some of the problems of Third World adolescents stem from poverty & political instability*. - Adolescents are more likely to be malnourished & to contract illnesses. - In many places, war & terrorism affect health and disrupt the government's ability to provide health services. - In sub-Saharan Africa, many adolescents are infected with HIV & AIDS. • *Other problems can be attributed to Westernization & cultural change*. - Adolescents are smoking in greater numbers. - Some are engaging in more non-marital sex beginning at earlier ages, increasing the chance of STDS.

What does it mean to be *anovulatory*?

• A girl's cycles are usually anovulatory (without ovulation) when her menstrual cycle begins.

What are the causes of acne?

• Acne is triggered by an increased amount of testosterone (which is why boys develop acne more than girls). • It has little to do with hygiene, masturbation, or diet; but, it can be worsened by cosmetics, friction, & stress.

Why do adolescents have inadequate diets?

• Adolescents have inadequate diets because (1) they skip breakfast, (2) they rely on snacks, (3) they eat only small quantities of nutritious foods, (4) they have an inadequate knowledge of nutrition, (5) social pressures may cause poor eating habits, (6) troubled family relationship & personal adjustment may cause poor eating habits, and (7) poor families cannot afford to buy proper food.

How much food do adolescents need? What are the dietary deficiencies of adolescents? How do these deficiencies differ among males & females?

• Adolescents need greater quantities of food. In fact, the stomach increases in size & capacity in order to digest the amount of food needed. • Adolescents also need the right nutrients; however, most have inadequate diets. They have *insufficient calcium* (due to inadequate intake of milk & dairy); *insufficient iron* (especially in girls, due to blood loss from menstruation); *inadequate protein* (mostly in girls who are dieting); and *insufficient vitamin A & B6*. • Adolescent girls have nutritional deficiencies more often than boys. This may be because girls eat less, are frequently on diets, or have additional needs from menstruation or pregnancy.

How do adolescent girls respond to menarche?

• Although some girls are pleased when menstruation starts, others have a negative view of menstruation. • This is common among early maturing girls, who are often less informed than their late maturing peers. • Many girls are negatively conditioned by advertisements that depict menstruation as a "hygienic crisis".

Discuss *anabolic steroids* & their prevalence among adolescents.

• Athletes sometimes take synthetic male hormones called *anabolic steroids* to increase their strength & endurance. • The use of androstenedione (an OTC food supplement thought to build muscle mass) by baseball stars may increase adolescent interest in steroids. • Although steroids increase muscle mass & reduce body fat, they produce many physical & emotional side effects. • Fortunately, the number of adolescents who use steroids is low.

How do levels of estrogens & androgens change during puberty?

• Both sexes produce estrogens & androgens. These hormones increase in small amounts during childhood. • As the ovaries mature, the level of estrogen increases dramatically & begins to vary with the menstrual cycle. The level of androgens also increase, but not as much. • As the testes mature, the level of testosterone increases dramatically. The level of estrogen increases very slightly.

What is adolescent self-esteem associated with?

• During adolescence, a large part of our self-esteem is tied with how physically attractive we feel.

Why do late maturing boys & early maturing boys engage in problematic behavior?

• Early maturers engage in problematic behavior, mostly smoking & alcohol use, to conform to older peers; late maturers engage in problematic behavior to appear more mature, gain social status, & raise their self-esteem. • It might be the presence of peer acceptance that determines whether off-time maturers will have problems. In one study, the early-maturing boys who were perceived as misfits/victims by peers engaged in undesirable behavior.

Discuss the experience of early-maturing boys.

• Early-maturing boys are larger, stronger, & more coordinated than peers, so they excel in competitive sports. • They enjoy social advantages, participate in more extracurricular activities, & are chosen for leadership roles. • They are more likely to become involved in heterosexual relationships, and they are more likely to abuse substances.

Discuss the experience of early-maturing girls.

• Early-maturing girls are the first to mature physically. •They are noticeably different from peers, which affects their self-esteem & distances them from peers. • They are more likely to hang out with older boys. • They are also more likely to experience internalizing disorders; to experience eating disorders; to perform delinquent acts; & to engage in early sexual behaviors.

What are the benefits of exercise? How much exercise do adolescents need?

• Exercise builds *physical fitness*, *reduces weight*, and promotes *psychological & mental health*. • Physical activity patterns developed in adolescence may continue into adulthood. • Adolescents need at least 30 minutes of moderately intense physical activity on all/most days of the week.

Describe the development of secondary sexual characteristics in females.

• First, girls develop pubic hair around age 12; two years later, they develop axillary hair; and finally, they develop body hair (especially on the arms & legs).

Describe the development of secondary sexual characteristics in males.

• First, pubic hair appears; two years later, axillary (underarm) hair appears; next, beard growth begins; and finally, the hairline becomes indented. • The voice changes due to the rapid growth of the larynx & the lengthening of the vocal cords across it; roughness of tone & unexpected pitch changes may last until 16-18.

What are some of the growth trends in adolescence?

• Girls grow most in height & weight at age 12; boys grow most in height & weight at age 14. • Girls are shorter & lighter than boys during childhood; however, because they mature earlier, girls are taller & heavier than boys in early adolescence. • Girls reach 98% of their adult height by 17, buy boys do not until they are 18.

How does lack of sleep affect adolescents? How much sleep do adolescents need; how much sleep do they get? How is this behavior related to *melatonin*?

• In one study, students who reported less sleep were more tired, depressed, & inattentive during the day. Some students even reported driving badly due to tiredness or falling asleep behind the wheel. • Adolescents need more sleep than preteens, but they stay up later to juggle homework, sports, & jobs. They are also more likely to socialize, play games, or watch TV at night. • This behavior is in part biological. Adolescents secrete *melatonin* (the hormone that the brain produces to induce sleep) two hours later than children or adults.

Discuss the experience of late-maturing boys.

• Late-maturing boys are the last to mature physically. • They are smaller, weaker, & less coordinated than peers. • They are characterized as less attractive & less popular. • They may become self-conscious & withdrawn. • However, late-maturing boys have better outcomes overall. They are the last to explore sexually, they are less likely to abuse substances, & they often do better academically.

Discuss the experience of late-maturing girls.

• Late-maturing girls are at a social disadvantage in middle school & high school because of their physical immaturity. • They are often bypassed in invitations to parties & social events, and they may be envious of their developed friends. • However, late-maturing girls have better outcomes overall. For example, late maturers don't experience the criticism of parent & other adults that early maturers do.

Where do males get their estrogens? Where do females get their androgens?

• Males get their estrogens from converting testosterone into estrogen. • Females get their androgens from their *adrenal glands*, which are located just above the kidneys & contain small amounts of male sex hormones. The ovaries also produce small amounts of androgens.

Discuss acne.

• Many teens spend countless dollars purchasing products to control their acne. • In addition, acne can lead to self-consciousness & social withdrawal.

What are the internal physical differences between males & females?

• Men's hearts & lungs are larger for their body size than are women's; thus, men have higher blood pressure & their blood contains more hemoglobin. • Men have more "fast-twitch" muscle fibers & women have more "slow-twitch" muscle fibers.

Why do merocrine glands & apocrine glands cause problems? Why do sebaceous glands cause problems? What are *papules* & *pustules*?

• Merocrine & apocrine glands secrete a fatty substance that produces body odor. • Sebaceous glands develop at a greater speed than the ducts through which they discharge oils, and as a result, the ducts may become plugged. - When ducts become plugged, they produce whiteheads & blackheads. If the plug becomes infected, a *papule* (tender, inflamed pink bump) or *pustule* (pus-filled pimple) will form.

What are the treatments for acne?

• Mild cases of acne respond to OTC creams that contain benzoyl peroxide or salicylic acid. • Severe cases require prescription medication (e.g. topical vitamin A, oral antibiotics, or estrogen-containing birth control pills).

How do adolescent girls feel about their body types?

• Most Caucasian adolescent girls are dissatisfied with their bodies & would like to be ectomorphic. • Girls who perceive themselves as overweight have lower self-esteem & are more likely to be depressed. • African & Hispanic American females are less likely to perceive themselves as overweight, whereas Caucasian & Asian females are often dissatisfied with their bodies.

How do adolescent girls feel about their body types?

• Most adolescent boys would like to be mesomorphic. • Generally, only noticeably heavy adolescent boys believe that they are overweight. • Slim boys may be dissatisfied with their bodies due to a lack of muscularity. • Boys who are short or heavy are often stigmatized. • Males feel better about their bodies as they move through adolescence, whereas females do not.

How is the obesity rate in the U.S. changing? Which races have the highest rates of obesity, and which races have the lowest rates of obesity? What conditions is adolescent obesity associated with?

• Obesity in adolescents is increasing in the U.S., and the rate by which adolescents are overweight continues to rise. • African American girls & Mexican American boys have the highest rates, and Caucasian girls have the lowest rates. • Adolescent obesity is associated with an increased risk for Type 2 Diabetes. It is also associated with high blood pressure & high cholesterol, which are precursors to heart disease.

What is the result of sexual maturation in adolescents?

• One result of sexual maturation is a developing preoccupation with sex. • Most adolescents engage in some form of sexual behavior (e.g. kissing, petting, masturbating, & intercourse).

What percentage of adolescents regularly participate in physical activity? How does this change over the course of adolescence? How does physical activity differ among different sexes & races?

• Only ½ of adolescents regularly participate in rigorous physical activity. • The amount of physical activity declines over the course of adolescence. • Adolescent girls are less likely to exercise than boys, and Black females are less likely to exercise than White females.

What is physical attractiveness related to in adolescence? What are the advantages of attractive adolescents?

• Physical attractiveness is related to an adolescent's positive self-evaluation, popularity, & peer acceptance. • Attractive adolescents are generally thought of in positive terms (e.g. warm, friendly, successful, intelligent). • Attractive adolescents are rated as having better peer & parent relations than unattractive adolescents.

Why do the physical changes associated with adolescence occur? What are *hormones*?

• Puberty is triggered when the brain starts directing various *endocrine glands* to increase their production of *hormones*. • *Hormones* are chemical messengers that flow through the bloodstream & affect what other cells do.

What is *locker-room syndrome*? What is *gynecomastia*?

• Some boys suffer *locker-room syndrome*, where they must undress & shower in front of others after physical education class. Those who are underdeveloped may feel uncomfortable around friends, and those who have started to develop may feel self-conscious about their new bodies. • Furthermore, many boys experience *gynecomastia*, a temporary enlargement of their breasts resulting from an excessive amount of estrogen in their systems.

How does spermatogenesis begin? What happens to sperm after spermatogenesis? What happens to sperm during ejaculation?

• Spermatogenesis begins when FSH & LH stimulate the production & growth of mature sperm cells in the testes. The total process takes about 10 days. • After spermatogenesis, the sperm migrate to the epididymis, where they may remain for up to 8 weeks. • During ejaculation, the sperm are carried from the scrotum to the trunk through the vas deferens. They eventually reach the seminal vesicles & prostate gland, which secrete seminal fluid to increase their mobility as they pass through the urethra & out of the penis.

What are the *Cowper's glands*? How do they mature during adolescence?

• The *Cowper's glands*, which also mature during adolescence, secrete a fluid that lubricates & neutralizes the acidity of the urethra for the passage of semen. This fluid may be seen at the glans during arousal & before ejaculation.

What is the *hypothalamus*? Which hormones does it produce?

• The *hypothalamus* is the emotional & motivational control center of the brain. It regulates functions such as hunger, hormonal production, menstruation, & sexual behavior. • During adolescence, it begins to produce *gonadotropin-releasing hormone (GnRH)*, which controls the secretions of LH & FSH by the pituitary.

What is the *vulva*? What are the *Bartholin's glands*?

• The *vulva* is the collective term for the external female sex organs. These include the *mons veneers* (fatty pad covering the pubic bone), the *labia majora* (large outer lips), the *labia minora* (smaller inner lips), the *clitoris*, & the *vestibule* (cleft region enclosed by the labia minora). • The *Bartholin's glands* are on either side of the vaginal opening & secret fluid during sexual arousal.

When do girls experience *menarche*?

• The adolescent girl experiences *menarche* around age 12. However, puberty may begin considerably earlier or later. • Menarche does not occur until maximum growth rates in height & weight have been reached. • The timing of menarche is partly due to genetic makeup & partly due to environmental factors.

How does pubertal timing affect adolescents?

• The age at which adolescents experience puberty affects how they feel about themselves & the expectations that others have of them.

How does the home environment affect pubertal timing?

• The age at which girls experience menarche is linked to the characteristics of their home environment. For example, family conflict leads to early menarche. • Some propose that family conflict lowers metabolism & hastens weight gain, which triggers menarche. Also, stress during childhood may create changes in the hypothalamus.

How is the age of sexual maturity changing? How does the age of sexual maturity differ among races, and why?

• The age of sexual maturity has been decreasing, primarily due to better health care & heavier adolescents. • African American girls hit puberty earlier than Caucasian girls, possibly because they have higher levels of body fat & their bodies produce more *leptin*, a hormone associated with the onset of puberty.

How do the testes & scrotum mature during adolescence? What is the *epididymis*, and how does it mature during adolescence?

• The growth of the testes & scrotum accelerates at 11-12, becomes rapid at 13-14, and slows thereafter. • The *epididymis* is a system of ducts, running from the testes to the vas deferens, in which sperm mature & are stored. Before puberty, the epididymis is large in comparison with the testes; after puberty, it is small in comparison.

How does testosterone influence the development of male bodies? How does estrogen influence the development of female bodies?

• The high level of testosterone in males causes their bones to grow thicker & become more prominent. It also encourages the growth of muscles & the growth of body hair. • The high level of estrogen in females encourages breast development & prompts the body to form a layer of subcutaneous fat. It also causes girls' hips to widen to facilitate childbirth.

Describe sex hormone regulation in males.

• The hypothalamus produces GnRH, which stimulates the pituitary gland to secrete FSH & LH. LH stimulates the testes to produce testosterone, and FSH stimulates sperm growth in the testes (*spermatogenesis*). • The level of testosterone is regulated by a negative feedback loop. GnRH stimulates production of LH, which stimulates production of testosterone. When the testosterone level rises, the hypothalamus reduces production of GnRH; when the testosterone level declines, the hypothalamus increases production of GnRH. • The level of FSH is regulated by an additional negative feedback loop. *Inhibin* is a hormone produced by *Sertoli cells* in the testes. When inhibin rises, FSH production is suppressed, and sperm production declines.

Describe sex hormone regulation in females.

• The hypothalamus produces GnRH, which stimulates the pituitary to secrete FSH & LH. These hormones stimulate the growth of egg cells in the ovaries and the production of estrogen & progesterone in the ovaries. • The level of FSH is regulated by a negative feedback loop. When the level of estrogen rises, the production of GnRH declines, which reduces the production of FSH.

How does the mortality rate change throughout adolescence? What is the most common cause of death? What percentage of deaths are due to accidents & violence?

• The mortality rate for younger adolescents (10-14) is lower than the rate for older adolescents (15-19). • The most common reason that adolescents die is car accidents. • Today, ¾ of adolescent deaths are due to accidents & violence. However, in the past, most adolescent deaths were due to natural causes. • Males (who are more likely to be violent & to take risks) are more likely to die than females.

How do the ovaries mature during adolescence? How many follicles do adolescents have in each ovary? How many ova ripen during the reproductive years? What are the *fallopian tubes*?

• The ovaries increase in size & weight during adolescence. • Every female is born with 400,000 follicles in each ovary. By puberty, this number has declined to about 80,000. • Only about 500 ova ripen during the reproductive years. • The *fallopian tubes* transport the ova from the ovaries to the uterus.

How does the penis mature during adolescence?

• The penis doubles in length & girth during adolescence, with the most rapid growth taking place between 14-16. • Genital growth usually takes 3 years to reach the adult stage, but there are individual differences. • The head of the penis (glans) is covered by a loose fold of skin (prepuce or foreskin).

How does the vagina mature during adolescence? How do the vulva & uterus mature during adolescence?

• The vagina increases in length and the mucous lining becomes thicker, more elastic, & darker. • The Bartholin's glands begin to secrete fluid, and the secretions change from basic to acidic. • The labia majora, the labia minora, & the clitoris enlarge greatly. The mons veneers becomes more prominent through the development of a fatty pad. • The uterus doubles in length.