Male Physiology

Question 1

What is the H released from the hypothalamus to stimulate the gonadotropes?

Answer 1

GnRH

Question 2

Which gonadotrope H is the primary stimulus for the secretion of testosterone by the testes?

Answer 2

LH

Question 3

What does FSH stimulate?

Answer 3

Spermatogensis

Question 4

Which hypothalamic nucleus releases GnRH?

Answer 4

Arcuate nuclei

Question 5

How often is GnRH released through the day?

Answer 5

intermittently a few mins at a time, once every 1-3 hours

Question 6

What G protein does the LH/FSH receptors use?

Answer 6

Gs

↑ cAMP

Question 7

Which cells secrete testosterone in the testes?

Answer 7

Leydig cells

Question 8

What will testosterone inhibit, when its concentrations are high?

think neg feedback

Answer 8

hypothalamus (to release GnRH)

Question 9

What does the SRY cause at the genital ridges?

Answer 9

causes them to differentiate into cells that secrete testosterone

Question 10

What sex characteristics does testosterone help develop?

Answer 10

Penis
Scrotum
Prostate
Seminal vesicles
Male genital ducts
NOT female stuff

Question 11

What can u administer to help the testes descend in a cryptorchidism pt?

Answer 11

gonatotropic H’s

it ↑ testosterone, which help descend them

Question 12

How much testosterone is produced during childhood?

Answer 12

little to none

Question 13

At puberty, testosterone levels increase, which stay high until what age?

Answer 13

50

Question 14

At what age does testosterone become 20-50% of the peak value?

Answer 14

80

Question 15

What does testosterone do to BMR and RBC production?

Answer 15

↑ it by 15%

Question 16

What is the H that’s released by the Sertoli cells that regualtes the secretion of FSH?

Answer 16

Inhibin

Question 17

What are the serum levels of LH in men > 18 y/o?

Answer 17

1.8-8.6 IU/L

18 at 18 until you’re 86

Question 18

What are the serum FSh levels in men before puberty?

Answer 18

0-5 mlU/ml

Question 19

What are the serum FSh levels in men during puberty?

Answer 19

0.3-10 mlU/ml

Question 20

What are the serum FSh levels in adult men?

Answer 20

1.5-12.4 mlU/ml

Question 21

What are the normal serum levels of testosterone in men?

Answer 21

300-1,000 ng/dL

Question 22

What is the specific transporter for T in the blood?

Answer 22

SHBG

Question 23

If T isnt bound to SHBG, what is it bound to?

Answer 23

Albumin

Question 24

What is the form of T in the blood which is the active form that moves into cells cytoplasm to bind to the androgen R’s?

Answer 24

Free T

Question 25

Which spermatogonia undergo 5 mitotic divisions to give 32 type B spermatogonia?

Answer 25

type A spermatogonic

Question 26

type B spermatogonia divide to form 64 of what cell?

Answer 26

primary spermatocytes

Question 27

Primary spermatocytes divide to form 128 of what cells?

Answer 27

secondary spermatocytes

Question 28

What is the final stage of spermatogenesis,w here the secondary spermatocytes divide again, which yields 512 of what cells?

Answer 28

Sperm

Question 29

Where do the spermatogonia lie in the seminiferous tubules?

Answer 29

on the inner surface in 2-3 layers

Question 30

When do spermatogonia begin to divide via mitosis?

Answer 30

Puberty

Question 31

Some spermatogonia undergo which process to yield primary spermatocytes?

Answer 31

Meiosis

Question 32

What is the genetic composition of the spermatids?

Answer 32

Haploid

Question 33

How long does spermatogenesis take?

Answer 33

74 days

Question 34

How long mus the sperm remain in the epididymus to become mobile?

Answer 34

18-24 hours

Question 35

What is the substance from the seminal vesicles that provides nutrients for the ejaculated sperm?

Answer 35

Fructose

Question 36

What is the substance from the seminal vesicel that makes the cervical mucus more receptive to sperm movement and causes reverse peristalsis in the uterus/tubes?

Answer 36

Prostaglandins

Question 37

Which gland secretes a thin, milky fluid that contains Ca++, citrate ion, PO4, a clotting enzyme, and profibrinolysin?

Answer 37

Prostate

Question 38

What is the pH of the prostatic fluid?

Answer 38

Alkaline

Question 39

What is the optimal pH for sperm’s motility?

Answer 39

6-6.5

Question 40

Which accessory sex gland secretes fluid during sexual stimulation to lubricate the tubes?

Answer 40

Bulbourethral/Cowper’s gland

Question 41

What bulk does each accessory gland give to semen?

sperm/vas deferens
bulbourethral
seminal vesicle
prostate

Answer 41

Sperm/vas deferens- 10%
Seminal vesicle- 60%
Prostate- 30%

Bulbourethral gland- slim

Question 42

What is the avg pH of semen?

Answer 42

7.5

Question 43

What is the fxn of the clotting enzyme from the porstate?

Answer 43

holds semen int he deep vagina

Question 44

What is the tick cap of the spermatozoon that is formed mainly from the golgi, and contains hyaluronidase and proteolytic enzymes?

Answer 44

Acrosome

Question 45

What is the structure of the flagellum of the spermatozoon?

Answer 45

central skeelton of 11 microtubules (anexome)

9+ 2 arrangement

Question 46

What does NO do to give u a boner?

Answer 46

Activates guanyl cyclase –> ↑ cGMP –> relaxation of arteries in corpora cavernosa and spongiosum

Question 47

Which SANS vertebral levels have nerves that pass to the genital organs through the hypogastric and pelvic sympathetic nerve plexuses to initiate emission?

Answer 47

T12-L2

Question 48

What 3 things can cause impotence?

Answer 48

Trauma to PANS nerves from prostate surgery
↓ T
Drugs

Question 49

Impotence may be a clue to what underlying condition in men?

Answer 49

HTN, diabetes, atherosclerosis

Question 50

What enzyme is inhibited by sildenafil?

Answer 50

PDE-5

Question 51

Inhibition of PDE-5 cause what to increase?

Answer 51

↑ cGMP