Male Reproductive Anatomy

Question 1

True or False -

The first full ejaculation with spermatozoa has the largest concentration of high quality sperm.

Answer 1

True

Question 2

What % of seminal fluid is produced by the prostate?

Answer 2

30%

Question 3

What is the role of prostaglandins in semen?

Answer 3

Facilitation of sperm transport within the female reproductive tract, via inducing peristaltic contractions; and induction of sperm motility

Question 4

What is the function of vas deferents?

Answer 4

Transport of spermatozoa from epididymis to ejaculatory ducts.

Question 5

What is the function of the epididymis?

Answer 5

Store sperm for maturation and transport it to vas deferens

Question 6

What are primordial germ cells?

Answer 6

Primordial germ cells (PGCs) are germline stem cells that give rise to gametes in vertebrates. They originate outside the embryo very early in development and migrate through the primitive streak into the posterior endoderm to the genial ridge.

Question 7

True or False -

Spermatogonia are 2N diploid cells with 46 chromosomes.

Answer 7

True

Question 8

What are Type A (dark) cells?

Answer 8

Type A (dark) cells; spermatogonial cells, undergo asymmetric division to produce a copy of itself (Ad) and a copy of Type A (pale) cell (Ap).

Question 9

What are Type A (pale) cells?

Answer 9

Type A (pale) cells; spermatogonial cells, undergo 5 repeated symmetric divisions to produce identical clones that differentiate into Type B spermatogonia.

Question 10

What are Type B (B) spermatogonia?

Answer 10

Type B (B) remains quiescent. Undergoes mitosis to produce diploid intermediate cells; primary spermatocytes.

Question 11

What happens to primary spermatocytes during puberty?

Answer 11

Primary spermatocytes (2N) undergo meiosis I where secondary spermatocytes (1N) are formed.

Question 12

What happens to secondary spermatocytes during puberty?

Answer 12

Secondary spermatocytes (1N) undergo meiosis II, or, spermiogenesis, where maturation processes come to completion forming mature spermatozoa.

Question 13

What is ZP3?

Answer 13

ZP3 is the glycoprotein in the zona pellucida which induces the acrosome reaction of sperm cells at the beginning of fertilisation.

Question 14

Name the two supporting cells in the seminiferous tubules?

Answer 14

Sertoli cell (has receptors for FSH) and leydig cell (has receptor for LH)

Question 15

What is the function of tight junctions in seminiferous tubules?

Answer 15

Blood-testis barrier includes tight junctions between somatic Sertoli cells that restricts solutes from crossing the paracellular space, protecting spermatozoa

Question 16

What occurs in the seminiferous tubules?

Answer 16

The seminiferous tubules are the specific location for meiosis (FSH) hormonal regulation of testis to produce sperm and seroli cells.

Question 17

True or False -

Leydig cells (interstitial cells) bind to LH to make testosterone.

Answer 17

True

Question 18

What are the two steps in the maturation of sperm prior to fertilisation taking place?

Answer 18

(1) the penultimate step (capacitation), sperm remains in female reproductive tract for approx. 7 hours; the outer membrane (acrosomal cap) dissolves. (2) acrosomal reaction takes places enabling the sperm to penetrate the zone pellucida, ultimately fertilising the egg.