ch 28 Reproductive System

Question 1

1. What are the functions of the reproductive system?

Answer 1

1. produces gametes, fertilization, produces reproductive hormones, & protects & nourishes a new individual

Question 2

Meiosis:

1. What is meiosis?
2. Somatic cells are ……………. (2n), whereas gametes are ………… (n).
3. In meiosis 1 the chromosome number is …………. .
4. In meiosis 2, the duplicated chromosomes are separated and produce …….. haploid gametes.

Answer 2

1. Meiosis is cell division that produces gametes in both sexes.
2. Diploid, haploid
3. Reduced
4. 4

Question 3

1. Where does sperm development aka spermatogenesis begin?
2. What are nurse cells aka sustenacular aka sertoli cells?
3. What do nurse cells secrete?

Answer 3

1. in the seminiferous tubules.
2. Cells that attach to the basement membrane and maintain a blood-testis barrier to protect and nourish developing sperm cells.
3. inhibin, androgen-binding protein, and fluid for sperm transport

Question 4

1. Spermatogonia undergo mitosis to produce ………… …………. .
2. Are primary spermatocytes diploid or haploid?
3. Primary spermatocytes form how many secondary spermatocytes? Are these diploid or haploid?
4. The 2 secondary spermatocytes form what? Are these diploid or haploid?
5. What process do spermatids undergo, and what do they form?

Answer 4

1. primary spermatocytes
2. diploid
3. 2. Haploid
4. 4 spermatids, haploid (n)
5. undergo spermiogenesis to form spermatozoa.

Question 5

1. The male accessory glands form …….% of the volume of semen. What are these accessory glands?
2. Seminal vesicles (glands) join the ampulla of the ………. ………… to form the ………….. duct.
3. Their secretion forms ……% of the semen volume. Why is this secretion alkaline?
4. Their secretion contains fructose, citric acid, prostaglandins to
   stimulate ………….. ………….. and …………. proteins. What is the purpose of these contents?

Answer 5

1. 95%, seminal vesicles, prostate gland and bulbourethral glands.
2. ductus deferens, ejaculatory
3. 60%, to counteract the acidity of the vaginal fluids
4. stimulate smooth muscle & clotting proteins. Nourish the sperm cells, to coagulate sperm after ejaculation, and prostaglandins help w/uterine contraction to move sperm in uterus.

Question 6

1. what gland encircles the urethra?
2. What % of the semen volume does it comprise? Is it alkaline or acidic?
3. What glands lie inferior to the prostate gland? What percentage of the semen’s volume do they form?
4. They make an ……… mucous to neutralize ……… in the urethra.

Answer 6

1. the prostate gland.
2. 30%, alkaline.
3. bulbourethral glands, 5%
4. alkaline, acids

Question 7

1. What stimulates the release of FSH and LH (in both sexes)?
2. What stimulates the interstitial cells to release testosterone (males)?
3. How does testosterone regulate the level of LH?
4. What is the stimulus for sustenacular cells (nurse cells) and spermatogenesis?
5. What hormone regulates FSH?

Answer 7

1. GnRH from hypothalamus
2. LH
3. Negative feedback which inhibits GnRH, hence LH secretion.
4. FSH and testosterone
5. Inhibin from nurse cells.

Question 8

1. How does testosterone affect the fetus?
2. How does testosterone affect the male at puberty?
3. How does testosterone affect the male after puberty?

Answer 8

1. Stimulates the development of the male brain, duct system, and genetalia
2. stimulates the development of male sex characteristics
3. stimulates male sexual behavior, spermatogenesis, the
   male sex drive, protein synthesis & maintains the male sexual characteristics

Question 9

1. What is oogenesis? When does this process begin?
2. In oogenesis, the cytoplasm is divided unequally to produce what structures?
3. Before birth, primary oocytes are formed by mitosis of ………….. and are arrested in which stage of mitosis?
4. When do the oocytes develop further?
5. When is a secondary oocyte released? In what stage of meiosis is this secondary oocyte? Will it finish meiosis?

Answer 9

1. The process of egg formation. Involves mitosis and meiosis. Begins in fetal development
2. One ovum and 2 or 3 nonfunctional polar bodies.
3. Oogonia, prophase 1.
4. After puberty the oocytes develop further each month.
5. in ovulation. In metaphase 2. Meiosis only completes if fertilization occurs.

Question 10

Follicle Development:

1. In what structure are oocytes produced?
2. What does a primordial follicle consist of? Until when are these present? What do they become?
3. What changes when a primordial follicle becomes a primary follicle?
4. What changes when a primary follicle becomes a secondary follicle?
5. What changes when a mature follicle forms?
6. At ovulation, what happens to the secondary oocyte?
7. The empty follicle collapses & forms the corpus luteum which secretes ………….. and …………….. .

Answer 10

1. In primordial follicles consisting of cells surrounding the developing oocyte.
2. a single layer of squamous cells called granulosa surrounding the oocyte. Present until puberty when they become primary follicles.
3. The granulosa cells enlarge and become cuboidal and the zona pellucida forms
4. fluid filled vesicles form and thecal cells arise on the outside of the follicle.
5. the fluid-filled vesicles form a single antrum, the oocyte completes meiosis I to form a polar body & a secondary oocyte (arrested in metaphase II)
6. It ejects from the antrum thru the ovary wall into the pelvic cavity.
7. progesterone & estrogen

Question 11

1. Just as in males, the female reproductive function is under …………. and …………. control.
2. The …………. cycle is the cyclic changes of the uterus in an adult non-pregnant female
3. What happens on day 1 of the uterine cycle?
4. When does the follicular (proliferative) phase begin?
5. When does the luteal (secretory) phase begin?

Answer 11

1. hormonal and neural
2. Uterine aka menstrual
3. Menstruation begins. The endometrium is sloughed off and lasts for 4-5 days.
4. as the endometrium regenerates
5. when ovulation occurs (usually day 14) and the uterine glands begin to secrete.

Question 12

1. The …………. cycle is the cyclic changes in the ovaries of an adult non pregnant female.
2. What hormone stimulates the release of LH and FSH?
3. Days 1-14 are the …………. phase. The anterior pituitary releases ………. which stimulates the development of up to 25 primary follicles.
4. What 2 hormones stimulate follicle growth and development? These same 2 hormones stimulate granulosa cells to secrete ……………. .
5. Developing follicles secrete ……………. which reduces FSH levels.
6. Rising ………… levels increases FSH and especially LH, an example of ………….. feedback.

Answer 12

1. Ovarian
2. GnRH
3. Follicular, FSH
4. FSH and LH, estrogen
5. inhibin
6. Estrogen, positive

Question 13

1. What surge causes ovulation? Does this also cause the oocyte to complete meiosis 1?
2. What happens to the remaining follicle cell after ovulation?
3. What does the corpus luteum secrete and what is its effect?
4. What does progesterone do?
5. If the oocyte is fertilized, what happens to it?
6. What happens if fertilization does not occur?
7. What hormones stimulates the start of a new ovarian cycle?

Answer 13

1. The LH surge, yes.
2. It becomes the corpus luteum.
3. Corpus luteum secretes progesterone (and a wee bit of estrogen). This suppresses GnRH and ultimately LH and FSH secretion.
4. maintains the endometroium in case of fertilization.
5. It completes meiosis 2. The embryo secretes hCG, and corpus luteum is maintained to keep producing progesterone.
6. declining levels of progesterone & estrogen leads to menstruation & the corpus luteum degenerates to become the corpus albicans
7. Rising GnRH, FSH, and LH