Male Reproductive Physiology

Question 1

What commonalities are found between sexes?

Answer 1

formation of gametes (sex cells) and hypothalamic/pituitary control of reproduction

Question 2

What is the main difference between meiosis and mitosis? Which process is involved in gametogenesis?

Answer 2

both processes involve one process DNA replication, however in meiosis, cells undergo cell division twice.

Meiosis is involved in gametogenesis: the formation of gametes

Question 3

T/F. Sex Cells are haploid and Sexually reproducing organisms are diploid.

Answer 3

True.

haploid means having one set of chromosomes
diploid means having 2 sets of chromosome

Question 4

What hormones are involved in the control of reproduction

Answer 4

GnRH (gonadotroplin releasing hormone)

LH: luteinizing hormone

FSH: follicle stimulating hormone

Question 5

Where is GnRH released from?

Answer 5

hypothalamus

Question 6

What is the relationship between the three hormones involved in reproduction control?

Answer 6

GnRH puslivity controls the release of whether LH or FSH is secreted from the anterior pituitary

Question 7

If there is a low frequency of GnRH, is it more likely that LH or FSH will be secreted?

Answer 7

FSH

Question 8

IF there is a high frequency of GnRH, is it more likely that LH or FSH will be secreted?

Answer 8

LH

Question 9

T/F. pusle frequency/amplitude does not change during development.

Answer 9

False. it does change during development

Question 10

Describe the initial process of creating sperm

Answer 10

the process, spermatogenesis begins during fetal development

1. spermatozoa (mature sperm) precursor spermatogonia will undergo mitosis
2. one of the cells that have been duplicated will be taken further to undergo meiosis. The other will continue to divide
3. the one that undergoes meiosis 1 will produce secondary spermatocytes (2)
4. Each spermatocyte will then undergo meiosis 2 and produce 2 spermatids each, for a total of 4 spermatids
5. Spermatids mature into spermatozoa
6. Spermiogenesis will occur where the spermatids will lose their cytoplasm and gain a tail

Question 11

Where is sperm stored? Why is this compartment a degree or two colder compared to the rest of the body?

Answer 11

Sperm is stored in the testes which are generally colder to stimulate healthy sperm development

Question 12

In a male after birth, where does sperm production start

Answer 12

in the seminiferous tubule

Question 13

In males, where does sperm mature in the testes

Answer 13

epididymis

Question 14

What makes sperm cells unique?

Answer 14

They have half the amount of genetic material than the rest of the cells in the body and they have proteins on their cell surface

Question 15

What is the significance of this differentiation of sperm and how may it be dangerous for their survival

Answer 15

they will look different that the rest of the cells and the immune system will see them as foreign and try to destroy them.

Question 16

what mechanism is put in place to prevent this immune attack on sperm?

Answer 16

Sertoli cells, which nurse and support sperm set up tight junctions between early and developing sperm to produce a blood-testes barrier so that no sperm make it into the blood

Question 17

Acrosome

Answer 17

contains hyaluronidase and across which breakdown the coat that covers the oocyte

Question 18

What is semen? is it different from sperm?

Answer 18

Sperm is in semen, but it only makes up 1% of semen content

The majority of semen is made up of water, enzymes, prostaglandins, and buffers to neutralize acids in urethra and female reproductive system

Question 19

Why do males need prostaglandins in their semen

Answer 19

prostaglandins produce smooth muscle contraction, which help push and move the semen out of the male body

Question 20

Where are the buffers that make up semen produced?

Answer 20

in the bulbourethral gland

Question 21

What is the basic journey of sperm out of the male body

Answer 21

1. sperm moves up Vas deferens, past the Seminal vesicles, Prostate and Bulbourethral gland through Urethra and Outside body

Question 22

How do the contents in semen help sperm?

Answer 22

1. assist with expulsion from testes
2. keep sperm at a healthy pH
3. move through female reproductive tract

Question 23

What cells nurture the developing spermatozoa

Answer 23

Sertoli cells

Question 24

What does FSH do in male reproduction?

Answer 24

stimulates Sertoli cells:
- supporting sperm development
secrete inhibin
- secretes androgen-binding protein

Question 25

inhibin

Answer 25

hormone that negatively regulates FSH

Question 26

What role does LH play in male reproduction

Answer 26

stimulates Leydig cells which secrete testosterone

Question 27

What is the difference between pre-pubescent and pubescent male testes

Answer 27

pre-pubescent testes volume is largely made up of Sertoli cells where as adult testes volume is made of germ cells and actual sperm

Question 28

Hypogonadism

Answer 28

decreased functional activity of testes
decreased production of androgens and inhibin and impaired sperm production

Question 29

primary hypogonadism

Answer 29

defect is in the gonad (testes)

this lowers testosterone, which suppresses the negative feedback loop of reproduction control hormones- increasing GnRH, LH, and FSH

Question 30

secondary hypogonadism

Answer 30

hypothalamic/ anterior pituitary damage that causes a decrease in GnRH, LH, FSH, and testosterone

Question 31

What has been shown to help treat male baldness

Answer 31

inhibitors of 5 alpha reductase because it decreases dihydro-testosterone (DHT)

Question 32

What does testerosterone do

Answer 32

Sex-Specific: promote spermatogenesis
Reproductive: increase sex drive and negative feedback on GnRH, LH, and FSH
Secondary sex: baldness, muscle growth, odour
Nonreproductive: protein synthesis, aggression, erythropoiesis- making of new blood