endocrine - repro

Question 0

isoform of 5a-reductase:

Expression starts at puberty

Answer 0

Type 1

Question 1

Testosterone and DHT synthesis

Answer 1

Aldrostenedione to testosterone (17B-HSD) to DHT (5a-reductase)

Question 2

isoform of 5a-reductase:

Found in skin - contributes to sebaceous gland activity and acne formation

Answer 2

Type 1

Question 3

isoform of 5a-reductase:
Found in male urogenital tract, skin, hair follicles and Liver
For masculinization of ext genitalia in utero

Answer 3

Type 2

Question 4

Leydig cell produces estrogen peripherally. Effects…

Answer 4

Bone maturation
Insulin sensitivity
Improves lipoprotein profile (increase HDL)

Question 5

60% of androgen is bound to

Answer 5

sex hormone binding globulin SHBG

Question 6

Androgen negative feedback effect on FSH and LH ..more on

Answer 6

LH

Question 7

Regulation of Sertoli cell function

Answer 7

Stimulated by both testosterone and FSH
Expresses FSH receptor
FSH stimulates synthesis of inhibin

Question 8

Loophole in male repro axis..

Answer 8

Intratesticular T level should be >100x more than circulating T level to maintain normal spermatogenesis

Question 9

Exogenous T level increases circulating T only

Answer 9

True

Question 10

Regulation of development of internal genitalia in male

Answer 10

Wolffian duct-Testosterone and presence of MIS

Question 11

Regulation of development of internal genitalia in female

Answer 11

Mullerian duct - absence of MIS

Question 12

Regulation of development of external genitalia in male

Answer 12

Presence of DHT

Question 13

Regulation of development of external genitalia in female

Answer 13

Absence of DHT

Question 14

GnRH neurons have been demonstrated in the feral hypothalamus by

Answer 14

9wks gestation

Question 15

Functional connections are established between GnRH neurons and portal system by

Answer 15

16wks AOG

Question 16

Characterized by low amplitude GnRH secretionas mirrored by LH secretion

Answer 16

Childhood period

Question 17

Characterized by a striking increase in amplitude of LH pulses with a lesser change in frequency

Answer 17

Puberty

Question 18

In adult male, LH is secreted in pluses approx every

Answer 18

2 hrs

Question 19

Seminiferous tubular dysgenesis

Answer 19

Klinefelter syndrome

Question 20

Genetic disorder in men with extra X chromosome.

Phenotypically male but with small testis and decreased germ cell

Answer 20

Klinefelter syndrome

Question 21

Results from hereditary defect of X chromosome gene controlling androgen receptor expression
Phenotypically female but male internal genitalia
Male pseudo hermaphroditism

Answer 21

Androgen insensitivity syndrome

Question 22

Due to decreased DHT formation

Answer 22

5a reductase deficiency

Question 23

Normal internal genitalia but incomplete masculinized external genitalia - ambiguous genitalia. Mistaken for females at birth

Answer 23

5a reductase deficiency

Question 24

Primary isolated gonadotropin deficiency due to inability of GnRH neurons to migrate to medico basal hypothalamus from nasal placode. With undescended testes (CRYPTORCHIDISM) and microphallus. Asso with anosmia

Answer 24

Kallmann syndrome

Question 25

Female repro cell which expresses LH receptor

Answer 25

Theca cells

Question 26

Female repro cell which produces androgen (primarily androstenedione)

Answer 26

Theca cells

Question 27

Theca cells expresses what enzyme

Answer 27

Cyp11a1, 3b-HSD, cyp17

Question 28

Female repro cell which expresses FSH receptor

Answer 28

Granulosa cells

Question 29

Granulosa cells expresses what enzymes

Answer 29

17b-HSD, cyp19

Question 30

Regulation of menstrual cycle when there is high freq GnRH pulses

Answer 30

LH production

Question 31

Regulation of menstrual cycle when there is low freq GnRH pulses

Answer 31

FSH production

Question 32

Most common cause of congenital hypogonadism

Answer 32

Gonadal dysgenesis or Turner syndrome

Question 33

Short stature, webbed neck, low se tears, shield-shaped chest, short 4th metacarpals and sexual infantilism

Answer 33

Turner syndrome

Question 34

Chronically a ovulation women with high androgen, estrogen, and LH levels

Answer 34

PCOS

Question 35

Diagnosis of PCOS requires 2 out of 3 of

Answer 35

1. Amenorrhea 2. Evidence of excess androgen secretion (acne, hirsutism) 3. Polycystic ovaries by ultrasound

Question 36

Primary defect of PCOS

Answer 36

Inappropriate signals between HP axis and ovary