Gametogenesis

Question 1

where is the spermatogonium present

Answer 1

inner wall of seminiferous tubules

Question 2

ploidy of spermatogonium

Answer 2

diploid (46 chromosomes)

Question 3

what happens to primary spermatocytes

Answer 3

first meiotic division to form 2 haploid secondary spermatocytes(23)

Question 4

What happens to secondary spermatocytes

Answer 4

second meiotic division to form 4 haploid spermatids(23)

Question 5

Spermiogenesis

Answer 5

formation of sperms(spermatozoa) from spermatids.

Question 6

spermiation

Answer 6

process by which sperms are released from the seminiferous tubules.

Question 7

what does increase levels of (GnRH) do

Answer 7

stimulates secretion of LH and FSH

Question 8

LH

Answer 8

acts at the leydig cells which stimulates secretion of androgens

Question 9

what do androgens do(males)

Answer 9

stimulate spermatogenesis

Question 10

FSH

Answer 10

acts on sertoli cells and stimulates the release of some factors to promote spermiogenesis

Question 11

Acrosome

Answer 11

a cap like structure that covers he haploid nucleus of the sperm which contains enzymes that help in fertilization

Question 12

middle piece of sperm

Answer 12

contains mitochondria which releases energy for motility

Question 13

how many sperms are secreted during coitus

Answer 13

200-300 million(60% have normal size and shape whereas 40% show vigorous motility)

Question 14

semen constituents

Answer 14

seminal plasma and semen

Question 15

when is oogenesis initiated

Answer 15

during embryonic development

Question 16

what happens to oogonia

Answer 16

undergoes meiotic division and stops at prophase-I and forms primary oocytes

Question 17

what are primary follicles

Answer 17

primary oocytes surround by granulosa cells

Question 18

how many follicles in ovary

Answer 18

60,000-80,000 in each ovary

Question 19

what are secondary follicles

Answer 19

more layers of granulosa cells and a new theca on the primary follicle.

Question 20

how are tertiary follicles formed

Answer 20

from secondary follicle which has a fluid filled cavity called antrum.(oocyte inside the follicle completes the first meiotic division) and then forms a Graafian follicle(mature).

Question 21

first meiotic division of primary oocyte

Answer 21

secondary oocyte(23) and a polar body. the secondary oocyte retains the nutrient rich cytoplasm of the primary oocyte.

Question 22

Zona pellucida

Answer 22

membrane on the secondary oocyte.

Question 23

ovulation

Answer 23

Graafian follicle ruptures to release the secondary oocyte(ovum) from the ovary.