Gametogenesis

Question 1

Meiosis:

Answer 1

Moves from 2n to n

Question 2

Spermatogenesis end size

Answer 2

Meiosis separates the cytoplasm equally.

Question 3

Stages of sperm:

Answer 3

germ cell - spermatogonium - primary spermatocyte - Secondary spermatocyte - Spermatids - Sperm cells

Question 4

Oogenesis: symmetrical or asymmetrical?

Answer 4

asymmetrical

Question 5

What bodies grow and fade as the egg matures?

Answer 5

Polar bodies containing excess DNA

Question 6

Sertoli cells

Answer 6

Provide nutrients for developing spermatids

Question 7

These structures allow flagellar bending

Answer 7

Dyneins

Question 8

What is broadcast spawning?

Answer 8

Release of large numbers of gametes into an aquatic environment

Question 9

Animal hemisphere

Answer 9

the upper hemisphere the usually contains the germinal vesicle (nucleus)

Question 10

Vegetal hemisphere

Answer 10

bottom hemisphere typically containing mRNAs

Question 11

GnRHs

Answer 11

Gonadotropin releasing hormones

Question 12

What are two common gonadotropins?

Answer 12

Luteinizing hormone (LH) and follicle stimulating hormone (FSH)

Question 13

Where is estrogen created?

Answer 13

Connective tissue cells in the ovary

Question 14

Where is progesterone created?

Answer 14

Made especially by the corpus luteum

Question 15

Estrogen and Progesterone together

Answer 15

inhibit hormone production by the hypothalamus and pituitary[inhibit gonadotrophin that causes ovulation, therefore stopping ovulation]

Question 16

Progesterone function

Answer 16

Other than linking with estrogen to stop ovulation, it thickens the uterine lining.

Question 17

hCG

Answer 17

Human Chorionic Gonadotropin : made by embryo, and stimulates the corpus luteum to maintain progesterone

Question 18

RU486 and Progesterone

Answer 18

binds to the progesterone receptor, but does not activate signaling. Overall works to prevent preparation of the uterus for embryonic development.

Question 19

Egg Jelly/ Cumulus Complex

Answer 19

Outer section of egg cell that sperm must digest.

Question 20

Vitelline envelope / Zona pellucida

Answer 20

Second outer shell of egg cell that sperm bind to

Question 21

Difference between oocytes and eggs

Answer 21

oocytes have not completed meiosis, whereas eggs have

Question 22

Most mammalian and amphibian oocytes are arrested in what phase?

Answer 22

Metaphase II

Question 23

What is MPF? [acronym]

Answer 23

Maturation Promoting Factor

Question 24

What is CSF [acronym]

Answer 24

Cytostatic Factor

Question 25

What is the relationship between CSF and MPF in regards to metaphase, and maturation?

Answer 25

Cytostatic factor causes arrest at metaphase II by PREVENTING the destruction of MPF.

Question 26

What does MPF do?

Answer 26

MPF promotes maturation, but also results in the arrest of the egg cell at metaphase II.

Question 27

How do egg cells progress beyond metaphase II?

Answer 27

During fertilization, Ca2+ levels rise in the cell, which destroys Emi2, allowing APC [anaphase promoting complex] to become active, progressing the cell.

Question 28

Can ES or iPS cells produce gametes?

Answer 28

Yes.