The Reproductive System

43. Which hormone (estrogen or progesterone) is in higher blood concentration during the follicular phase of the ovarian cycle? during the luteal phase?;

-follicular phase: estrogen -luteal phase: progesterone

39. What is the role of sperm penetration in the development of an ovum?;

-in humans, the secondary oocyte arrests in metaphase ii, and it is this cell (not a functional ovum) that is ovulated. if a sperm does not penetrate an ovulated secondary oocyte, the oocyte deteriorates. but if sperm penetration does occur, the oocyte quickly completes meiosis ii, yielding one large ovum and a tiny second polar body ***sperm penetration triggers completion of meiosis II which produces an ovum and second polar body ***review: •In each cycle, one of the rescued by FSH follicle is selected to become the dominant follicle oCompletes meiosis 1 oProduces a polar body and the secondary oocyte oSecondary oocyte contains almost all of the plasma of the primary oocyte oIn humans the secondary oocyte arrests in metaphase II - secondary oocyte is the cell that is ovulated oif a sperm does not penetrate this ovulated secondary oocyte, it quickly deteriorates (oocyte) oif sperm penetration occurs- it quickly completes meiosis II and will yield one large ovum and the secondary polar body

52. What health risks are increased in post-menopausal women (who do not participate in hormone replacement therapy)?;

-increased risk of osteoporosis dur to accelerated loss of bone mass; increased risk of CV disease due to a gradual rise in serum cholesterol levels and depression is also a major health risk

45. Describe the origin and function of a corpus luteum. What is the life span of a corpus luteum if fertilization does not occur?;

Origin: forms after ovulation at the site of the ruptured follicle incorporating theca internal and granulosa cells Function: SECRETES PROGESTERONE, SOME ESTROGEN & INHIBIN which decreases stimulation of LH and FSH

21. Describe the general structure of an ovary and of an ovarian follicle.;

Ovaries -Held in place by ovarian ligament, mesovarium, suspensory ligament (which contains major b.v. and nerves that supply ovary) -Ovaries flank uterus on each side -Have almond shape -Enclosed by tunica albuginea (dense irregular CT) -This is externally surrounded by ET called germinal ET -Gametes are produced in this outer cortex of ovary -Inner stroma contains large b.v. and nerves Ovarian follicles are embedded in the cortex of the ovary - each follicle consists of an oocyte surrounded by one or more layers of cells -When surrounding cells form single layer, called follicular cells -As follicle develops additional cell layers form; when more than one cell layer is present, cells are called granulosa cells

17. Explain how testosterone secretion is regulated (after puberty), with mention of GnRH, FSH and ICSH, inhibin, and feedback inhibition.

hypothalamic-pituitary-gonadal axis Higher plasma levels of GnRH, FSH & ICSH @ puberty GnRH stimulates release of FSH and LH which directly stimulate the testes inhibin exerts negative feedback on hypothalamus and pituitary gland

2. What are the male and female gametes called?

male: sperm female: ova

3. What are the male and female sex hormones?

male: testosterone (main), FSH, LH (ICSH), ABP, inhibin, GnRH female: estrogen and progesterone (main), FSH, LH (ICSH), ABP, inhibin, GnRH

37. At birth, primary oocytes are arrested in what phase of meiosis?;

prophase I

31. Which blood vessels within the uterine wall undergo growth and degeneration during the menstrual cycle?;

spiral arteries repeatedly degenerate and regenerate; their spasms actually cause the functionalis layer to be shed during menstruation

4. Describe the structure and function of the scrotum.;

thin wall of skin midline septum seen externally as raphe -encloses testes dartos muslce: wrinkles scortal skin cremaster muscle: elevates testes in cold temps to keep them warmer

33. Describe in order (beginning at the external body surface) the structures through which sperm pass as they make their way toward a waiting oocyte.;

vaginal orifice->vaginal canal(lumen)->cervix-(external os->cervical canal->internal os)->lumen of uterus->uterine aka fallopian tube

9. Identify the male accessory sex glands.;

seminal glands (2) bulbourethral glands (2) prostate gland

41. Identify and describe the three major phases of the ovarian cycle.;

*normally lasts 28 days Follicular phase (pre-ovulatory phase): Day 1 - Day 14 - period of follicle growth - regulated by FSH -*stages: -maturation of the primordial follicle involves pre-astral and astral phases 1. first stage: pre-astral; intrafollicular paracrine such as cytokines and growth factors control the oocyte and development 2. phase 2 directed by FSH and LH -by about day 6 one tertiary follicle becomes the dominant follicle (estrogen and inhibit secreted by dominant follicle->decreased FSH secretion->atresia of remaining tertiary follicles; dominant follicle continues to develop; primary oocyte of dominant follicle complete meiosis 1; phase is variable in length, but lasts from day 1-14 in a typical cycle -primary oocyte becomes secondary oocyte and gets arrested in metaphase ii of meiosis ii Ovulation: Day 14 - LH surge triggers ovulation a. high levels of estrogens during last part of follicular phase exert POSITIVE FEEDBACK on LH & GnRH -> surge in LH = ovulation and formation of corpus luteum -secondary oocyte ejected into peritoneal fluid Luteal Phase: Day 14-18 - most constant in duration, lasts for 14 days - corpus luteum forms at site of ruptured follicle - incorporates granulosa and & theca internal cells - corpus luteum secretes progesterone (some) estrogen, inhibin -> inhibits LH and FSH secretion - stratum functionalis thickens - if no fertilization, corpus luteum lasts for only 14 days a. fibroblasts invade and convert the corpus luteum to a corpus albicans (scar tissue) b. progesterone and estrogen levels fall, leading to: onset of menstruation, increased gonadotropin secretion -if fertilization and pregnancy occur, embryonic chorion secretes human chorionic gonadotropin (hCG) - extending lifespan of corpus luteum for about 3 more months (placenta picks up role at 3 months to secrete progesterone and estrogen) -ruptured follicle collapses, antrum fills with clotted blood and corpus hemmorrhagicum is eventually absorbed and remaining granulosa cells enlarge and alongside theca internal cells form endocrine structure = corpus luteum which immediately secretes progesterone and estrogen

32. Describe the female external genitalia.;

*usually referred to as the vulva and these structures lie external to the vagina; the components are: 1. mons pubis - fatty, rounded area covering the pubic symphysis; covered with pubic hair after puberty 2. labia majora - homologous to the scrotum in males; longitudinal folds of skin that extend posteriorly from mons pubis; pubic hair present 3. labia minora - medial to labia majora; thin folds of tissue - no adipose tissue or pubic hair; anteriorly converge to form a hood of tissue over clitoris (prepuce) 4. clitoris - homologous to the glans penis in males; small rounded tissue projection of erectile tissue 5. vestibule - region surrounding the vaginal and external urethral orifices (between labia minora) *ducts of several pairs of glands open into the vestibule: a. paraurethral glands - homologous to the prostate gland b. greater vestibular glands - homologous to the bulbourethral glands c. lesser vestibular glands - open into the vestibule and watery secretion to keep membrane of vestibule moistened

28. How does the uterine tube participate in helping to move the oocyte toward the uterus?;

- around time of ovulation, tube performs complex movements to capture oocytes; bends to drape over the ovary while the fimbriae stiffen and sweep the ovarian surface. - beating cilia on the fimbriae then create currents in the peritoneal fluid that tend to carry an oocyte into the uterine tube, where it beings its journey toward the uterus -oocyte is carried toward uterus by a combination of muscular peristalsis and the beating cilia

51. What are the female secondary sex characteristics?;

- growth & development of breasts - subcutaneous fat deposition (especially in the breasts & hips) - widening & lightening of the pelvis (adaptations for childbirth) - influences appearance of axillary and pubic hair

53. Explain the role of the ANS (parasympathetic and/or sympathetic divisions) in producing the female sexual response.;

-Arousal - parasympathetic - relaxation of vascular smooth muscle in genital region & secretion by vaginal & vestibular glands -Orgasm - sympathetic - nervous stimulation produces systemic effects (inc muscle tension, HR & BP), rhythmic contractions of uterus (reverse peristaltic contractions to draw sperm into the reproductive tract), vagina and perineal muscles NO REFRACTORY PERIOD

18. What are the male secondary sex characteristics?;

-features induced in non reproductive organs by the male sex hormones (mostly testosterone) that develop at puberty -pubic axillary and facial hair, chest hair -deepening voice as larynx enlarges -skin thickens/becomes oilier -bones grow/inc in density -skeletal muscles increase in size and mass -boosts basal metabolic rate and influences behavior -basis of male libido (testosterone is basis of male libido whereas basis of female libido is adrenal androgen, DHEA)

49. What menstrual cycle events are associated with the fluctuating levels of ovarian hormones?;

-FSH- regulation of the follicular phase and it effects the cells of the secondary and Graafian follicles; it causes follicular maturation and is secreted by the anterior pituitary -LH: targets interstitial cells to produce androgens, stimulates the primary oocyte of the dominant follicle to complete its first division; it increases local vascular permeability, it stimulates the release of prostaglandins; it also triggers inflammatory response that promotes release of enzymes that help weaken the ovarian wall; it is also responsible for transforming that ruptured follicle into the corpus luteum; it is secreted by the anterior pituitary -GnRH is secreted by the hypothalamus and it stimulates FSH and LH secretion -Estrogen - secreted by the dominant follicle and the corpus luteum; it promotes development of reproductive structures; it promotes secondary sex characteristics; it supports the growth spurt it enhances HDL levels (good type of cholesterol); facilitates calcium uptake; increases protein anabolism and triggers LH surge Progesterone - secreted by the corpus luteum, it establishes and maintains the uterine cycle; it thickens cervical mucous; it helps prepare the breasts for lactation; it also decreases uterine contractions during pregnancy; it helps maintain stratum functionalis (what is sloughed off during menstruation and grows anew during each cycle); essential for maintaining pregnancy should it occur -Inhibin - secreted by the granulosa cells and by the corpus luteum; it has negative feedback on the FSH and LH release (job is to inhibit)

14. Describe the structure of a mature sperm cell, and tell how each part of the sperm (i.e., head, midpiece, tail) contributes to its overall function.;

-Head: contains the nuclear material (DNA) and has acrosome at front tip to help penetrate the egg when they come in contact -Midpiece: contains mitochondria that provide ATP for locomotion -Tail: a flagellum to whip around in a corkscrew motion to project it through female reproductive tract

22. Distinguish between the following in terms of structure and stage of development: primordial follicle; primary follicle; secondary follicle; antral (Graafian follicle); corpus luteum.;

-Primordial follicle: immature oocyte surrounded by one layer of flattened follicle cells; very small -Primary follicle: 2 or more layers of cuboidal or columnar granulosa cells surround oocyte; follicle itself is growing in size and thickening -Secondary follicle: fluid-filled pockets are present between layers of granulosa cells -Mature follicle: fluid-filled cavity (antrum) is very large - bulges from surface of ovary; ovulation occurs when mature follicle ruptures, ejecting oocyte -After ovulation, mature follicle becomes corpus luteum (which will deteriorate and become corpus albicans that marks spot where follicle had been)

26. In what stage of meiosis are primary oocytes at birth? What hormone causes the resumption of meiosis in females following the onset of puberty?;

-at birth, they are arrested in prophase I of meiosis I; at puberty, you have the LH surge which leads the completion of meiosis I and the LH surge facilitates progression into meiosis II; however, meiosis II can only be completed if the egg is fertilized by sperm, so arrested in metaphase II until sperm fertilizes egg and meiosis II can complete resulting in a zygote

*56. List the female developmental changes, with approximate age at occurrence, as a result of hormonal changes at puberty.;

-breast development about 10 years old (caused by the estrogen); sexual hair (armpits, pubic) around 11 years old; first period - around 12.5 years old (should come about 2 years after breast development) -more curves, axillary hair, acne, a growth spurt about 1 to 2 years before menstruating

40. What is the significance of the unequal distribution of cytoplasm, which results in the formation of polar bodies, during oogenesis?;

-ensures that a fertilized egg has ample nutrients for its six to seven day journey to the uterus ; in the uterine tube where the egg and sperm come together; this fertilized egg has; if you're lacking nutrient-containing cytoplasm than the polar bodies will degenerate and die

20. Explain the role of the parasympathetic and sympathetic divisions of the ANS in producing the male sexual response (i.e., erection and ejaculation).;

-erection is under parasympathetic control parasympathetic: causes release of NO which causes vasodilation of b.v. and filling of erectile bodies with blood; also causes secretion by bulbo-urethral glands (erection) -ejaculation is under sympathetic control sympathetic: strong peristalsis in reproductive ducts and accessory glands, constriction of bladder sphincters, series of rapid and powerful contractions of smooth muscle in erectile bodies of penis (ejaculation)

35. What hormones regulate the synthesis of milk and its ejection?;

-estrogen and progesterone

11. Describe the composition of semen.;

-milky white, sticky - comprised of sperm, testicular fluid, accessory gland secretions -Sperm and seminal fluid -Prostaglandins: -Hormone relaxin and certain enzymes -ATP -antibiotic chemicals destroy some bacteria -Clotting factors -alkaline

27. What is ovulation?;

-occurs when the ballooning ovary wall ruptures and expels the secondary oocyte, still surrounded by its corona radiata, into the peritoneal cavity -occurs on day 14 of typical cycle -follicle ruptures

*54. Determine the best approach for the history and physical examination (child, adolescent).;

-older child (adolescent) - have parents leave the room to ask more sensitive questions relation to sexual behavior/identity, drugs/alcohol ; but it is important to know that you need a chaperone for the physical exam -child: talk to the child, ask in a way that they understand and talk to the parent for follow-up information; parent in the room the whole time

36. Identify the characteristics of the various phases of follicular development: primordial follicle, primary follicle, secondary follicle, antral follicle.;

-ovarian follicles are specialized structures in which oocytes grow and undergo meiosis -the earliest type of follicle, whose wall consists of a single layer of flattened epithelial-type cells (called follicular cells), is called a primordial follicle (2 million in each ovary at birth) -when a primordial follicle is activated (this occurs almost a year before its possible ovulation), the squamouslike cells surrounding the primary oocyte grow, becoming cuboidal cells, and the oocyte enlarges. the follicle is now called a primary follicle -next, the follicular cells proliferate, forming a stratified epithelium around the oocyte. as soon as more than one cell layer is present, the follicle is called a secondary follicle and the follicle cells take on the name granulosa cells. (grows tremendously during this stage!) -the secondary follicle stage ends when a clear liquid begins to accumulate between the granulosa cells, producing the early vesicular (antral) follicle. when six to seven layers of granulosa cells are present, the fluid between the granulosa cells coalesces to form a large fluid-filled cavity called the antrum (cave). the presence of the antrum distinguishes vesicular follicles from all prior follicles (preantral follicles).

19. Explain the mechanism that produces an erection of the penis.;

-part of a parasympathetic reflex which causes the release of nitric oxide (NO)-->vasodilation of local blood vessels-->erectile bodies enlarge and engorge with blood -spongiosum prevents urethra collapse -secretion by bulbourethral glands (thick and viscous and lubricate glans penis to make easier to insert into vagina) -can be caused by a number of sexual stimuli

23. In what stage is the developing oocyte in each of the follicles listed above (#22)?;

-primordial, primary, and secondary follicle have primary oocyte -secondary oocyte is with Graffian follicle

*55. Define puberty.

-process leading to physical and sexual maturation that involves the development of secondary sexual characteristics as well as growth, changes in body composition, and psychosocial maturation

8. What is the function of the epididymis?;

-sperm are temporarily stored here until ejaculatoin -learn how to swim and they take on their classic shape in the epididymis -absorb excess testicular fluid -pass nutrients to sperm stored in the lumen -sperm moved through antimicrobial proteins including defensins sperm ejaculated from here phagocytize old sperm

12. List in order and describe the major steps in spermatogenesis. Your answer should make reference to steps involving mitosis, meiosis I, or meiosis II; and also make reference to primary spermatocytes; secondary spermatocytes; spermatids; sperm.

-spermatogenesis is the production of haploid sperm cells and occurs in the seminiferous tubules -spermatogenic cells undergo cell divisions to produce sperm cells when they are triggered by high levels of androgen -Type A daughter cells remain at the basement membrane and undergo mitosis -Type B daughter cells have loose contact with the basement membrane and they enlarge and differentiate into primary spermatocytes (still diploid) -primary spermatocytes undergo meiosis I and then become secondary spermatocytes (haploid) -secondary spermatocytes undergo meiosis II and 4 spermatids are produced that are connected by little bits of cytoplasm called cytoplasmic bridges which allow access to info on the Y chromosome to ensure proper development -final stage is spermiogenesis where the spermatids mature to sperm. Takes about 24 days. Cells package acrosomal material by Golgi apparatus at the head end

6. Describe the location and general function of each of the following testicular cells: spermatogenic cells (spermatogonia); sustenacular cells (Sertoli cells); interstitial cells (Leydig cells).;

-spermatogenic: undergo cell division to produce sperm cells-- spermatogonia are the stem cells of sperm that undergo mitosis and are most immature spermatogenic cells (don't leave basement membrane ever until puberty), at puberty the spermatogonia mitotically divide into type a or type b cells-- type b cells move toward lumen and become primary spermatocytes which will undergo meiosis I-- secondary spermatocytes (haploid)--meiosis II-- 4 spermatids -sustenacular (sertoli): extend from basement membrane to lumen to surround developing spermatogonia (spermatogenic cells) --projections connected by tight junctions that divide internal lumen of seminiferous tubule into two compartments- inner compartment (adluminal) that includes meiotically active cells so this compartment is protected from immune system, these cells also secrete testicular fluid, move cells along in lumen, phagocytize faulty cells, PRODUCE INHIBIN (when sperm counts too high to give feedback on hypothalamus and ant pituitary secretion) -interstitial (leydig): surround seminiferous tubules in aerolar CT-- secrete and produce androgens in response to LH (ICSH)

13. Distinguish between spermatogenesis and spermiogenesis.;

-spermiogenesis is the final step of spermatogenesis where the 4 spermatids are modified. they are elongated shed excess cytoplasm and form a tail -acrosomes full of hydrolytic enzymes will penetrate the zone pellucida of eggs by positioning themselves around the nucleus at head of sperm to be able to get in. mitochondria go near tail to power the movements. centrioles become flagellum.

*57. List the male developmental changes, with approximate age at occurrence, as a result of hormonal changes at puberty.;

-testicular enlargement around age 11; sexual hair and increase in penis size around age 12 -axillary, facial hair, typically more acne in men, growth spurt and voice changes in men after sexual hair development; puberty and growth complete around age 18

48. Identify and describe the three major phases of the uterine (menstrual) cycle.;

1. Menstrual phase - menses lasts for about the first 5 days of a 28-day cycle - menstrual flow consists of the blood, tissue fluid, mucus & epithelial cells that are derived from the stratum functionalis - menstruation occurs when levels of estrogens and progesterone decrease (deterioration of corpus luteum) - left with stratum basalis 2. Proliferative phase - estrogens released by the developing follicles stimulates repair and thickening of the endometrium - mucus plug in cervical canal prevents bacteria, but thins near the end of this stage - OVULATION OCCURS in the ovary at the end of this stage 3. Secretory phase (ovulation marks beginning of secretory phase) - overlaps w/ luteal phase - progesterone and estrogens (secreted by corpus luteum) cause continued development of the endometrium and secretion by endometrial glands -phase begins immediately after ovulation - growth and thickening of stratum functionalis -phase ends when progesterone & estrogen levels reach low level (as the corpus luteum deteriorates)

29. Name in order (outermost to innermost) the three tissue layers of the uterine wall.;

1. perimetrium: the incomplete outermost serous layer 2. myometrium: the bulky middle layer, composed of interlacing bundles of smooth muscle. the myometrium contracts rhythmically during childbirth to expel the baby from the mother's body 3. endometrium: the mucosal lining of the uterine cavity. it is simple columnar epithelium underlain by a thick lamina propr.. if fertilization occurs, the young embryo burrows into the endometrium (implants) and resides there for the rest of its development

30. Name the two strata of the endometrium. Which of these two layers undergoes cyclic growth and sloughing-off in response to changing blood levels of the ovarian hormones?;

1. strata functionalism, or functional layer undergoes cyclic changes in response to blood levels of ovarian hormones and is shed during menstruation (approximately every 28 days) 2. stem cells found in the thinner, deeper stratum basalis, or basal layer, form a new functionalis after menstruation ends.

5. Describe the structure of the testes.;

2 tunics -tunica vaginalis on outside: serous- derived from peritoneum -tunica albugenia: deeper, divides testes into lobules and each lobule has 1-4 seminiferous tubules (which go to straight tubules, rates testis, efferent ductules, to epididymis to ductus deferens to ejaculatory duct to urethra)

47. Describe the feedback loops (positive and negative) involved in regulating GnRH, FSH, and LH secretion in the various stages of the ovarian cycle.;

During FOLLICULAR PHASE: Day 1: GnRH stimulates FSH and LH Later... LH stimulates estrogen production Rising estrogen levels exert NEGATIVE FEEDBACK on the hypothalamus and anterior pituitary (LH & FSH inhibited, GnRH inhibited) but simultaneously ENHANCES estrogen output by intensifying effect of FSH on follicle maturation. Inhibin exerts NEGATIVE FEEDBACK on FSH release; only dominant follicle survives this dip. Then, POSITIVE FEEDBACK -> high estrogen levels reach critical blood conc, and exert positive feedback on brain and anterior pituitary = LH Surge LH Surge -> triggers ovulation and formation of corpus luteum Rising progesterone and estrogen + inhibin from corpus luteum = NEGATIVE FEEDBACK on hypothalamus and anterior pituitary release of LH and FSH ***blood levels of lipids and leptin lead to puberty onset, GNrh stimulates FSH and LH secretion; FSH and LH stimulate follicles to grow, mature, and secrete sex hormones; as estrogen levels in the plasma rise, they exert a negative feedback on the hypothalamus and the anterior pituitary (inhibiting GNrH release -within an ovary, estrogen enhances output of more estrogen by intensifying the effect of FSH -inhibin is released by granulosa cells that also exerts negative feedback so it exerts the negative feedback on the FSH release during follicle maturation so only the dominant follicle will survive this dip in FSH -although the initial small rise in estrogen inhibits the hypothalamus and the pituitary, the high estrogen level produced by the dominant follicle has the opposite effect -Then, POSITIVE FEEDBACK -> high estrogen levels reach critical blood conc, and exert positive feedback on brain and anterior pituitary = LH Surge LH Surge -> triggers ovulation and formation of corpus luteum Rising progesterone and estrogen + inhibin from corpus luteum = NEGATIVE FEEDBACK on hypothalamus and anterior pituitary release of LH and FSH

*58. Describe the stages of the Tanner Sexual Maturity Rating scale for males and females.;

FEMALE: -Tanner stage 1: pre-adolescent and see elevation of the nipple only; no pubic hair or breast development -Stage 2: breast bud development; elevation of the breast and nipple becomes a small mound; sparse growth of long, slightly-pigmented downy hair along the labia stage 3: further development of elevation of the breast and the areola (no separation of contours); darker, coarser, curlier hair that is spread over the pubic symphysis -stage 4: projection of the areola, and the nipple projects with it to form a secondary mound; course and curly pubic hair as an adult would; covering more area than stage 3 but not as much hair as stage 5 -stage 5: mature stage, the projection of the nipple only, while the areola recedes to the general contour (nipple protrudes); quality and quantity of adult hair extends to the thighs, but not on the abdomen MALE: -stage 1: pre-adolescent, no pubic hair -stage 2: sparse growth of long, slightly pigmented, downy hair at the base of the penis; penis has slight or no enlargement; testes and scrotum are larger, are reddened and altered in texture -stage 3: darker, coarser, curlier hair, that spreads sparsely over the pubic symphysis; penis will enlarge in length, and testes and scrotum are also enlarged -stage 4: this coarse curly hair is that of an adult, covering more than stage 3 but not as much as stage 5 and does not include the thighs; penis is enlarged in width and length with development of the glands; testes and scrotum are enlarged and become darker -stage 5: quality and quantity of adult hair reaches the thigh but does not go onto the abdomen; penis, tests, and scrotum are adult size and shape

16. The following secretions are involved in regulating male reproductive function. Describe the effects of each and identify the cells that secrete them: follicle-stimulating hormone (FSH), luteinizing hormone (LH) -in males, also known as interstitial-cell stimulating hormone (ICSH), androgen-binding protein (ABP) gonadotropin-releasing hormone (GnRH) inhibin, testosterone

FSH- stimulates spermatogenesis indirectly because stimulate sustenacular cells to release ABP LH (ICSH)- causes interstitial cells to secrete testosterone in soft CT around seminiferous tubules ABP- keeps concentration of testosterone around spermatogenic cells high ihibin- also released by sustenacular cells-- when sperm count is high-- negatively feeds back on ant pituitary to slow FSH secretion testosterone- synthesized by cholesterol- main source is testes but adrenal glands in both males and females also release androgens in small amounts, triggers spermatogenesis, libido, secondary sex characterisitics, and rising levels inhibit GnRh to regulate and maintain normal levels of gonadotropin secretion

42. Describe the relative blood concentrations of both estrogen and progesterone during the three phases of the ovarian cycle (i.e., when does the blood concentration of each hormone increase? decrease?);

Follicular phase: - estrogen secretion goes up - progesterone secretion Ovulation - estrogen secretion is high and the high level establishes a positive feedback on LH, FSH, and GnRH - shortly after ovulation, estrogen levels decline (dominant estrogen-secreting follicle is damaged) Luteal phase - BEGINNING: progesterone secretion goes up, some estrogen is secreted -> NEGATIVE FEEDBACK - END: decreased progesterone and estrogen -estrogen is highest in the follicular stage leading up to ovulation and the LH surge -estrogen starts to decrease in the luteal phase as progesterone increases due to the production of the corpus luteum

44. What hormonal event triggers ovulation and causes the ruptured follicle to develop into a corpus luteum?;

LH surge

50. The following hormones are involved in regulating female reproductive function. Describe the effects of each hormone and identify the cells that secrete the hormone: follicle-stimulating hormone (FSH) luteinizing hormone (LH) gonadotropin-releasing hormone (GnRH) estrogen, progesterone inhibin

Menstrual phase (triggered by decrease of estrogen and progesterone because the corpus luteum just deteriorated) -proliferative phase, see an increase in estrogen and progesterone due to the LH surge Secretory phase (drop in estrogen followed by increase and then decrease again; and progesterone will increase and then decrease at the end; both levels reach a low level at the end of the secretory phase)

7. Describe the general structure and function of the penis.;

The penis is a structure suspended from the perineum. The penis together with the scrotum make up the external genitalia. -penis portion is divided into three regions: root, body and glans penis. -prepuce: loose skin covering and is often removed during circumscision. Internally-- -penis contains the urethra and three columns of erectile tissue: corpus spongiosum surrounds the urethra, corpora cavernosa (2) are paired dorsolateral (top) bodies that begin at the crus proximally which is attached to the ramus of the ischium/pubis and ends distally before the glans penis

24. What is the role of the theca interna?;

cells express receptors for luteinizing hormone (LH) to produce androstenedione, which via a few steps, gives the granulosa the precursor for estrogen manufacturing. After rupture of the mature ovarian follicle, the theca interna cells differentiate into the theca lutein cells of the corpus luteum.

38. Development of which broad category of follicle, pre-antral or antral, is regulated by the gonadotropins, FSH and LH?;

during the follicular phase of each ovarian cycle, a cohort of vesicular follicles is stimulated by rising levels of FSH to continue to grow. As FSH levels begin to drop in the middle of the follicular phase, one of these growing astral follicles is selected, becoming the dominant follicle that continues to grow.

46. What is the effect of human chorionic gonadotropin (hCG) on the corpus luteum?;

expands the lifespan of corpus luteum for about 3 more months

25. At what stage of the ovarian cycle the dominant follicle for the next ovarian cycle selected from the cohort of tertiary follicles in the ovaries?;

follicular phase: by about day 6 one tertiary follicle becomes the dominant follicle

34. Describe the general structure and function of the mammary glands of the breasts.;

function: produce milk to nourish a newborn baby structure: modified sweat glands that are really part of the integumentary system (skin). each is contained within a rounded breast within HYPODERMIS (superficial fascia), anterior to the pectoral muscles of the thorax. slightly below center of each breast is a ring of pigmented skin , AREOLA, which surrounds NIPPLE. large sebaceous glands in AREOLA make it slightly bumpy and produce sebum that reduces chapping and cracking of the nipple. autonomic nervous system controls of smooth muscle fibers in areola and nipple cause nipple to become erect when stimulated by tactile or sexual stimuli and when exposed to cold internally: 15-25 lobes that radiate around and open at nipple. lobes are padded and separated from each other by fibrous CT and fat, interlobar CT forms suspensory ligaments that attach breast to underlying muscle fascia and overlying dermis within lobes are lobules that contain alveoli that produce milk -> lactiferous ducts that open to outside at nipple; deep to areola, each duct has dilated region called lactiferous sinus where milk accumulates during nursing

10. Describe the secretions of each of the above glands (#9).;

seminal glands: yellow, account for 70 percent of semen vol, enhance sperm motility, contains fructose to provide fuel for ATP synthesis in flagellum prostate: milky, activates sperm, accounts for 1/3 fluid vol bulbourethral: thick, clear mucus- pre cum, neutralizes acidic urine in urethra, lubricates glans penis prostaglandins decrease viscosity of cervical mucus

15. Name (in order) the ducts through which a sperm travels as it moves from the testis to the body exterior.;

seminiferous tubules→straight tubule→rete testis→efferent ductules→epididymis→ductus deferens→ampulla→ejaculatory ducts→urethra (prostatic, membranous, penile/spongy)

1. Name and describe the location of both the male and female gonads.

testes (male): lie within the scrotum, outside of the abdominopelvic cavity Ovaries (female): inside abdominopelvic cavity