Reproductive Lecture 1

Question 1

What is the most important part of the Y chromosome?

Answer 1

SRY (sex determining region)

contains Testis Determining Factor (TDF)

Question 2

XY mice w/o SRY develop _______

Answer 2

ovaries

Question 3

XX mice with SRY develop _________

Answer 3

testis

Question 4

Loss of 1 X chromosome from female results in _________________________________

Answer 4

ovarian dysgenesis but not loss of female ducts/genitalia

Question 5

Do meiosis I and II result in haploid daughters?

Answer 5

yes

Question 6

True or false: male meiosis is continuous process while female is punctuated

Answer 6

true

Question 7

Where does oogenesis arrest before puberty?

Answer 7

substate of prophase of meiosis I (diplotene stage)

Question 8

When does meiosis complete?

Answer 8

upon fertilization

Question 9

Spermatogenesis develops how many daughter cells per germ cell? What about oogenesis?

Answer 9

Spermatogenesis: 4
Oogenesis: 1 (plue polar bodies)

Question 10

how do oogonia replicate in the ovary?

Answer 10

Mitosis

Question 11

what is atresia?

Answer 11

lots of eggs/oogonia thrown away (occurs right before birth)

Question 12

How many eggs do women have at birth?

Answer 12

2.5 million

Question 13

How many sperm are produced per day?

Answer 13

200 million

Question 14

When does spermatogenesis begin?

Answer 14

puberty

Question 15

What are 4 problems that can lead to defects in genetic sex?

Answer 15

1) Aneuploidy (change in # of chromosomes)
2) Mosaicism (different genotypes in different cells)
3) Chimerism (different zygotes that fuse)
4) Structural Errors (recombination)

Question 16

Is gondal development hormone dependent?

Answer 16

NO (gonads produce the hormones, it can’t be)

Question 17

Sertoli cells are like ____________ cells in the female

Answer 17

granulosa

Question 18

What do sertoli cells produce?

Answer 18

anti mullerian hormone

Question 19

Leydig cells are like _____________ cells in the female

Answer 19

Theca

Question 20

What do Leydig cells produce?

Answer 20

testosterone

Question 21

What do the germ cells go on to become?

Answer 21

spermatogonia or oogonia

Question 22

What direct the specific development of gonads?

Answer 22

germ cells

Question 23

Development of the _________ (XY): seminiferous tubules, spermatogonia, sertoli cells, leydig cells

Answer 23

medulla

Question 24

Development of the _________ (XX): secondary sex cords, oogonia, theca cells, granulosa cells

Answer 24

cortex

Question 25

Are there exclusive female or male hormones?

Answer 25

NO, both sexes have similar hormones and receptors -- dimorphism is due to differences in amounts of individual hormones

Question 26

What two hormones are necessary for male genital duct development?

Answer 26

1) testosterone (keep wolffian ducts) | 2) AMH (degrade mullerian ducts)

Question 27

True or false: take out ovaries and testes and you still get mullerian ducts

Answer 27

TRUE

Question 28

What do the wolffian ducts become?

Answer 28

epididymis, vas deferens, seminal vesicles, ejaculatory duct

Question 29

What 2 functions does AMH have?

Answer 29

1) causes mullerian duct atrophy | 2) coordinates development and stimulate of Leydig cells

Question 30

What do mullerian ducts develop into?

Answer 30

fallopian tubes, cervix, upper vagina

Question 31

Do female structures require estrogen to develop?

Answer 31

NO but they do require it to achieve normal size

Question 32

If TDF doesnt direct testicular development before 9 weeks, what happens?

Answer 32

an ovary develops

Question 33

What enzyme converts testosterone to DHT?

Answer 33

5a reductase

Question 34

What is responsible for male genitalia development?

Answer 34

DHT (via androgen receptors)

Question 35

What blocks 5a reductase?

Answer 35

Finesteride

Question 36

Define Klinefelter's

Answer 36

XXY seminiferous tubule dysgenesis (have wolffian duct and regressed mullerian) low testosterone because Leydig cells are hit hard by stimulatory pathways (LH) and estradiol starts getting produced

Question 37

What is Turner's syndrome?

Answer 37

XO (streak genitalia, never developed ovaries)

Question 38

Define male pseudohermaphroditism

Answer 38

have female external genitalia but testes

Question 39

What is AIS? (androgen insensitivity)

Answer 39

XY but no receptor for androgen so external genitalia is female (have testes which are making hormones but no way to process it)

Question 40

What testicular cells are stimulated by LH?

Answer 40

Leydig (L-->L)

Question 41

What testicular cells are stimulated by FSH?

Answer 41

Sertoli

Question 42

Which cells secrete inhibin?

Answer 42

Sertoli

Question 43

What effect does testosterone have on the hypothalamus and pituitary?

Answer 43

inhibits it

Question 44

What enzyme makes estradiol?

Answer 44

aromatase

Question 45

What does LH do in controlling testosterone production?

Answer 45

controls rate-limiting reaction (cholesterol to pregnenolone)

Question 46

Describe how testosterone travels through the blood?

Answer 46

45% bound to SHBG 55% bound to albumin and CBG 2% free