Sperm and their Origins

Question 1

What is the head/cap of the sperm called?

Answer 1

Acrosome

Question 2

What lies posterior to the acrosome of sperm?

Answer 2

Nucleus

Question 3

Where is the mitochondria located in the sperm?

Answer 3

Midpiece

Question 4

Fetal gonad forms from a bipotential primordia. How does it occur in males?

Answer 4

The medulla develops into a testis and the cortex degenerates

Question 5

Fetal gonad forms from a bipotential primordia. How does it occur in females?

Answer 5

The cortex develops into an ovary and the medulla degenerates

Question 6

Why can male gametes increase in number postnatally?

Answer 6

Because they arrested at mitosis and can resume again

Question 7

What are the two types in cells in the Seminifeous tubules?

Answer 7

Sertioli cells

Leydig cells

Question 8

What is the role of the Sertoli cells?

Answer 8

Nourishment of the spermatozoa

Question 9

Which set of cells form of the Blood-Testis barrier?

Answer 9

Myoid cells

Question 10

What are Myoid cells?

Answer 10

A set of cells which form the Blood-Testis barrier

Question 11

What is the sperm stem cell called?

Answer 11

Spermatogonium

Question 12

Describe the change in chromosome number during Spermatogenesis

Answer 12

1. Begins diploid (2n)
2. Replicates DNA (2n to 4n)
3. Chiasma forms
4. Cells divide to yield 2 x 2n
5. No second round of DNA replication
6. Cells divide from 2n to 1n

Question 13

1 Sperm stem cell can make how many Type A1 Spermatogonium?

Answer 13

16

Question 14

16 Type A1 Spermatogonium can make how many Type B cells?

Answer 14

32 Type B

Question 15

32 Type B cells can make how many resting primary spermatocytes?

Answer 15

64

Question 16

The primary spermatocyte is diploid or haploid?

Answer 16

Diploid

Question 17

The secondary spermatocyte is diploid or haploid?

Answer 17

Haploid

Question 18

What are the four sub cell types in Spermatogenesis?

Answer 18

SpermatoGOnia
SpermaTOcytes
SperMAtids
SpermaTOZoa

(Go to ma toz)

Question 19

What is the role of LH in males?

Answer 19

Acts on the Leydig cells to produce Testosterone (4 - 10 mg)

Testosterone acts on the hypothalamus in a negative feedback loop to reduce LH synthesis

Question 20

What is the principle Androgen hormone in males?

Answer 20

Testosterone

Question 21

What is the role of FSH in males?

Answer 21

FSH binds to receptors on Sertoli cells, and stimulates production of Androgen receptors

Question 22

What is the potent form of Testosterone, and how is it converted from Testosterone?

Answer 22

5-alpha DHT, via reductase

Question 23

What is the male equivalent of Theca cells?

Answer 23

Leydig cells

Question 24

What is the male equivalent of Granulosa cells?

Answer 24

Sertoli cells

Question 25

What receptor does the Leydig cells have?

Answer 25

LH receptor

Question 26

What receptor does the Sertoli cells have?

Answer 26

FSH receptor

Question 27

How much sperm is the normal range per ml?

Answer 27

15 million per ml

Question 28

What is the name given to “low sperm count”?

Answer 28

Oligospermia

Question 29

What is the name given to “complete absence of semen”

Answer 29

Aspermia

Question 30

What is the name given to the “complete absence of sperm”

Answer 30

Azoospermia

Question 31

What is the name given to “low motility of sperm”

Answer 31

Asthenozoospermia

Question 32

What is the erectile tissue of the penis?

Answer 32

Corpora cavernosa

Question 33

What is the mechanism of action of Sildenafil?

Answer 33

PDE5 inhibition