L2: Male Reproduction

Question 1

the breeding soundness exam evaluates what aspects

Answer 1

• bull fitness
• semen quality
• libido
• ability to copulate

Question 2

site of spermatogenesis

Answer 2

seminiferous tubules (lumen)

Question 3

what are the cell types found in the seiminiferous tubules

Answer 3

• germ cells (spermatogonia)
• sertoli cells

Question 4

cell type found in the CT (interstitial) of testes

Answer 4

• leydig cells (testosterone)

Question 5

testes produce what 2 essential products

Answer 5

• sperm
• testosterone

Question 6

sperm move from the seminiferous tubules through the rete testes and into the ______for storage and maturation

Answer 6

Epididymis

Question 7

process by which spermatogonia (germ cells) are converted to spermatozoa (sperms)

Answer 7

spermatogenesis

Question 8

packaging and maturation of spermatozoa is called

Answer 8

spermiogenesis

Question 9

release of spermatozoa from Sertoli cells into lumen of seminiferous tubules

Answer 9

spermination

Question 10

during this, 2 divisions create 4 diploid primary spermatocytes

proliferation of diploid germ cells

Answer 10

mitosis

Question 11

characterized by 2 divisions:
- diploid germ cells get converted into haploid spermatocytes
- two divisions create 16 spermatids
- * single strand of one chromosome

Answer 11

meiosis

Question 12

sperm cells don’t complete cyotkinesis during meiosis so the 4 daughter cells remain connected, forming a _____?

Answer 12

syncytium
* ensures haploid cells contain either X or Y chromosome

Question 13

the rate of spermatogenesis is constant, and set by _______ within sertoli cells

Answer 13

retinoic acid

Question 14

tight junctions between sertoli cells form a …..

Answer 14

blood testes barrier
prevents immune cells from accessing spermatozoa

Question 15

early spermatids remain joined by _______ bridges

Answer 15

cytoplasmic bridges

Question 16

what cells produce androgen binding protein

Answer 16

sertoli cells

Question 17

sertoli cells are stimulated by ______ and ________

Answer 17

testosterone and FSH

release inhibin

Question 18

what is hypogonadism

Answer 18

smaller than normal testicular size, results in below normal sperm counts

Question 19

the # of ______ cells that ocur in development determines the spermatogenic potential of the testes

Answer 19

sertoli cells

Question 20

what is the importance of gap junctions between spermatocytes and sertoli cells

Answer 20

permit the transfer of nutrients

Question 21

2 points during male development when sertoli cells develop

Answer 21

• at birth and puberty

Question 22

what do seminal (vesicular) vesicles produce

3 things

Answer 22

• prostaglandins
• fructose
• clotting factor

Question 23

prostate secretions

Answer 23

bicarbonates makes an alkaline fluid

Question 24

what hormone stimulates cholesterol desmolase within Leydig cells to produce testosterone

Answer 24

Lutenizing hormone (LH)

Question 25

FSH promotes secretion of _____ and ______ from sertoli cells

Answer 25

inhibin and androgen binding protein (ABP)

Question 26

where in the testes is testosterone produced

Answer 26

Leydig ccells

Question 27

what concentrates testosterone in the seminiferous tubules

Answer 27

androgen binding protein (ABP)

Question 28

testosterone circulates in peripheral blood bound to....?

Answer 28

sex hormone binding globulins (SHBG)

Question 29

what enzyme converts testosterone into estradiol

Answer 29

aromatase

Question 30

what enzyme converts testosterone into dihydrotestosterone (DHT)

Answer 30

5α-reductase

Question 31

what is the rate limiting step in the male steroid biosynthetic pathway

Answer 31

Lutenizing hormone (LH) it increases the affinity of cholesterol desmolase to cholesterol

Question 32

cryptorchid testes can produce normal _______ but few ______

Answer 32

normal - testosterone fewer - spermatozoa

Question 33

T/F fibroelastic penises are firm when not erect

Answer 33

T

Question 34

what are the steps in the neuroendocrine activation of sexual stimulation

Answer 34

* sensory stimulus * stimulus of nerves in supraoptic + paraventricular nuclei * release of oxytocin from posterior pituitary * transport of spermatozoa into ejaculatory positon * contractions of SM in distal tail of epididymis and ductus deferens

Question 35

corpus cavernosa and corpus spongiosum are in what component of the penis

Answer 35

shaft

Question 36

erection is achieved by what 3 things

Answer 36

1. higher brain activity (env stimulus) 2. mechanical stimulation of glans 3. parasympathetic impulses from sacral erection generation center (S2-S4)

Question 37

what is the role of parasympathetics in erection

Answer 37

* release of NO in penis causes sm to relax and increases blood flow

Question 38

when penis is flaccid, the helicine arteries are ....

Answer 38

contracted

Question 39

when the penis is erect, the helicine arteries are ....

Answer 39

relaxed (Caused by NO)