Chapter 20 - Reproduction

Question 1

The germ cells or [] are made in the testes and ovaries by [] and contain 23 chromosomes

The [] is formed after fusion of sperm cell and ovum and contains [] chromosomes.

Answer 1

1. Gametes, meiosis
2. Zygote, 46 chromosomes

Question 2

Cells that give rsie to sperm - []

Cells that give rise to ova - []

Answer 2

Spermatogonia

Oogonia

Question 3

What is the gene that codes for TDF (testis-determing factor)?

Answer 3

SRY

Question 4

The early-appearing Leydig cells in embryonic testes secretes large amounts of androgens - which androgen primarily?

Answer 4

Testosterone

Question 5

What are the embryonic, reproductive accessory sex organs ducts for males and females?

Answer 5

• Male - wolffian (meonephric) ducts
• Female - mullerian (paramesonephric) ducts.

Question 6

In males - Sertoli Cells secrete [] [] factor, that causes regression of the mullerian ducts.

Answer 6

Mullerian inhibition Factor

Question 7

The secretion of testosterone, from the [] cells, causes growth of wolffian ducts ultimately leading to the male reproductive accessory organs: [] , [], [] , []

Answer 7

1. Leydig Cells
2. Epididymis, Ductus (vas) deferens, seminal vesicles, ejaculatory duct

Question 8

FSH and LH are produced and secreted from where?

Answer 8

• Anterior Pituitary

Question 9

What is the hormone produced in the hypothalamus that stimulates the secretion of FSH and LH from the anterior pituitary?

Answer 9

GnRH - gonadotropin-releasing hormone

Question 10

What are the 3 primary effects on the gonads from the gonadatropic hormones (FSH and LH)?

Answer 10

1. stimulation of spermatogenesis or oogenesis
2. stimulation of gonadal hormone secretion
3. maintenance of the structure of the gonads.

Question 11

Whats the first flow (menstrual cycle) of a woman called?

Answer 11

Menarche

Question 12

What are the 2 components of the testes and what does each component do?

Answer 12

1. Seminiferous Tubules
   
   1. this is where spermatogenesis occurs
2. Interstial Tissue
   
   1. Contains Leydig Cells - secrete testosterone

Question 13

In Males -

FSH acts upon the [] [], specifically [] cells, stimulating [] in the seminiferous tubules

LH acts upon the [] [], stimulating the secretion of []

Answer 13

1. Seminiferous Tubules, Sertoli Cells, Spermatogenesis
2. Leydig Cells, testosterone

Question 14

Does inhibin act as a negative feedback mechanism for LH?

Answer 14

• No, testosterone acts as the negative feedback component towards LH
• Inhibin acts as negative feedback on the secretion of FSH from the anterior pituitary

Question 15

Where are spermatogonia found in the seminiferous tubule?

Are they diploid or haploid?

Answer 15

• They are found at the outermost region of the seminiferious tubule, right against the basal lamina.
• These are diploid. (they will become haploid though)

Question 16

How do Sertoli cells aid in the transformation of spermatids to spermatozoa?

Answer 16

Sertoli cells phagocytize the “residual bodies” of cytoplasm surrounding the spermatids.

Question 17

What are the 2 tissue layers of the penis that fill with blood during erection?

Answer 17

1. Corpora Cavernosa - dorsal
2. Corpus Spngiosum - ventral

Question 18

Which enzyme is activated by NO in the penis to convert GTP into cGMP.

What does cGMP indirectly do to create an erection?

Answer 18

1. Guanylate Cyclase
2. cGMP closes Ca2+ channels.
   
   1. Fall in intracellular Ca2+ causes smooth muscles to relax and corpora cavernosa to relax and blood vessles to dilate = erection!

Question 19

What enzyme breaks down cGMP, specifically in the penis to cause erectile dysfunction?

What are 2 medications that inhibit this enzyme?

Answer 19

1. Phosphodiesterase (PDE)
2. Viagra, Cialis

Question 20

What are the 3 layers of the uterus?

Answer 20

• Perimetrium - outer layer of connective tissue
• Myometrium - smooth muscle layer
• Endometrium - inner epithelial layer
  
  • Stratum basale
  • Stratum functionale - grows and sheds during menstruation

Question 21

What is a follicle called once it is mature, it’ll have a single fluid- filled cavity?

Answer 21

Graafian Follicle

Question 22

The theca of the ovary produces [] in response to LH stimulation.

[] is convereted to estradiol by the enzyme aromatase located in the [] cells of the follicle.

Answer 22

1. Testosterone
2. Testosterone, granulosa

Question 23

What does FSH do to the follicle?

Answer 23

• Stimulates increased amounts of aromatase in the granulosa cells.
• This will increase the amount of estradiol in the blood as follicles grow under FSH stimulation.
  
  • Testosterone is converted to estradiol by aromatase

Question 24

If a follicle stops growing it will become [] - regression term the applies the follicle did not rupture.

This is a type of apoptosis

Answer 24

Atresia

Question 25

What is the corpus albicans?

Answer 25

* It is a corpus lutuem from a previous non-fertile cycle that regresses to a nonfunctional state.

Question 26

Unlike the ovarian follicle, the corpus luteum secretes two sex steroid hormones: [] and []

Answer 26

Estradiol and progesterone

Question 27

The cyclic changes in the endometrium are called [], [], and [] phases...

Answer 27

Menstrual Proliferative secretory

Question 28

How long does the follicular phase last? What is happening with the follicles during this phase? What are the level of ovarian hormones during this phase? What stimulates these hormones release?

Answer 28

1. Day 1 of the cycle to Day 13 (Highly variable) 2. 1 follicle will reach maturity and become a **graafian follicle** 1. other primary follicles can grow into secondary follicles 3. Ganulosa cells secrete an increasing amount of **estradiol** 1. **​**estradiol levles are at their highest concentration in the blood 2 days before ovulation (Day 12ish)

Question 29

The rapid increase in what hormone causes the LH surge? What does this LH surge due to the follicle?

Answer 29

1. Estradiol 2. Causes the wall of teh graafian follicle to rupture

Question 30

LH causes the empty follicle to become what "new" structure? What does this structure secrete?

Answer 30

Corpus Luteum estradiol and progesterone

Question 31

High levels of progesterone (and a little estradiol) have what "type" of effect on the release of FSH and LH?

Answer 31

Negative Feedback affect.

Question 32

During what Ovarian stage does the "Proliferative phase" of the endometrium take place?

Answer 32

Follicular

Question 33

During the proliferative phase [] secreted by the developing follicles promotes growth of the []

Answer 33

estradiol Stratum Functionale of the endometrium

Question 34

During the secretory phase, the increased secretion of [] from the [] stimulates the development of the uterine gland. What happens to the endometrium during this phase?

Answer 34

1. progesterone, corpus luteum 2. The endometrium becomes thick, vasuclar and spongy. 1. The uterine gland becomes engorged with glycogen so it will be well prepared if fertilization occurs.

Question 35

[] [] occurs as a result of a fall in ovarian hormone secretion during the late luteal phase.

Answer 35

Menstrual phase.

Question 36

T/F Progesterone level increase and Estrogen levels decrease at the end of the secretory phase/beginning of menstruation?

Answer 36

False. Estrogen levels increase and progesterone levels decrease

Question 37

What hormones can actually inhibit lactation?

Answer 37

Estrogen and Progesterone

Question 38

What are the 3 main functions of estrogen during the female "cycle?"

Answer 38

* Growth of ductile tissue, fatty deposits in breasts * Promotes Prolactin - acts on breast tissue growth preparing mamary gland for lactation * Growth and contractile responsiveness of uterine muscle to Oxytocin * Does not stimulate the muscle to contract though!

Question 39

What are the main functions of Progesterone during female "cycle?"

Answer 39

* Growth glandular portion of the breast * Suppresses contractile activity in uterine smooth muscle * Maintains the secretory phase of the uterus