Week 2: Testis Development

Question 1

These cells are a finite number @ birth

Answer 1

sertoli cells

Question 2

Germ cells (gonocytes) migrate to the wall of the testes to become what?

Answer 2

spermatogonial stem cell

Question 3

Identify the green, blue, and red cells of the testis

Answer 3

green = sertoli cells
blue = peritubular myoid cells
red = germ cells –> SSC

Question 4

Name this structure of the testis

Answer 4

Ductus deferens

Question 5

Name this structure of the testis.

Answer 5

Body of epididymis

Question 6

Name this structure of the testis.

Answer 6

Head of Epididymis

Question 7

Name this structure of the testis.

Answer 7

Lobule

Question 8

Name this structure of the testis.

Answer 8

Seminiferous Tubule

Question 9

Where are leydig cells located?

Answer 9

On the outside of the tubules
(in interstitial tissue)

Question 10

What regulates leydig cell’s production of testosterone?

Answer 10

LH release from anterior pituitary

Question 11

What are the two peaks of androgen seen in the male?

Answer 11

1) in fetus before birth –> ensures external male genitalia (masculinisation)
2) puberty

Question 12

Controlled by FSH release from the anterior pituitary and androgen release from leydig cells
- aids in spermatogenesis

Answer 12

Sertoli cells

Question 13

These cells form the ‘blood testis barrier’ BTB –> tight junctions between these cells “seal off” the lumen of the tubule
- prevents the immune system from recognizing the haploid sperm cells as ‘foreign’

Answer 13

Sertoli Cells

Question 14

What cells secrete AMH?

Answer 14

Sertoli Cells

Question 15

contractile cells of the testis
- androgen-dependent
- essential for normal spermatogenesis

Answer 15

Peritubular Myoid Cell

Question 16

Smooth muscle in the scrotum capable of sustained contraction, elevating testes in cold environments

Answer 16

Tunica dartos

Question 17

Muscle continuous with internal abdominal oblique muscle, capable of short-term contraction during fear or excitement

Answer 17

Cremaster muscle

Question 18

a signaling molecule produced by Sertoli cells that acts in a paracrine manner to regulate testis development, specifically targeting Leydig cells to produce androgens and INSL3

Answer 18

Desert Hedgehog (Dhh) molecule

Question 19

When is the last division in spermatogenesis?

Answer 19

when the secondary spermatocyte (haploid with double chromatids) splits into haploid single chromatids
(i.e. completion of meiosis 2)

Question 20

Name the order of sperm maturity from location (basement membrane upwards) (5)

Answer 20

Spermatogonia –> primary spermatocyte –> secondary spermatocyte –> spermatid –> mature spermatid (spermatozoa)

Question 21

Functions to induce sperm maturation
- add fertile and motility
- tail acts as a storage area for sperm

Answer 21

Epididymis

Question 22

What type of membrane is the epididymis?

Answer 22

pseudostratified, columnar epithelium with stereocilia