Pleh

Question 1

What’s the order of spermatogenesis?

Answer 1

Spermatogonia
Primary spermatocyte
Secondary spermatocyte
Soermatids
Spermatozoa

Question 2

What’s the order of oogenesis?

Answer 2

Oogonia
Primary oocyte
Large primary oocyte
Secondary oocyte
Ovum

Question 3

Where do primordial germ cells originate?

Answer 3

Extra embryonic tissue

Question 4

How do primordial germ cells migrate into the embryo?

Answer 4

Via the gut and into the genital ridge, multiplying as they go

Question 6

What does the genital ridge give rise to?

Answer 6

Somatic cells of the gonad

Question 7

What do the primordial germ cells do once they reach the genital ridge?

Answer 7

Meiosis to produce gametes

Question 8

How are spermatogonia produced?

Answer 8

PGCs multiply during migration

Question 9

When are spermatogonia arrested?

Answer 9

G1

Question 10

How are spermatocytes produced?

Answer 10

After birth and in adults, diploid spermatogonia undergo mitosis to generate spermatocytes

Question 11

How are spermatids formed?

Answer 11

Spermatocytes undergo meiosis to produce haploid spermatids. Incomplete cytokinesis forms syncytia

Question 12

What produces spermatozoa?

Answer 12

Spermatids differentiation

Question 13

What do the carbohydrate lytic enzymes digest?

Answer 13

Beta-N-acetylglucosaminidase

Question 14

What’s the arrangement of microtubules in the axoneme?

Answer 14

2 central singlet surrounded by 9 doublet microtubules

Question 15

What’s the function of Dynein?

Answer 15

Use energy from ATP hydrolysis to slide microtubules in axoneme past one another

Question 16

What’s the difference in meiosis between spermatogenesis and oogenesis?

Answer 16

Spermatogenesis: meiosis before differentiation
Oogenesis: meiosis after differentiation

Question 16

How are oogonia generated?

Answer 16

PGCs multiply during migration to generate diploid oogonia

Question 18

How are primary oocytes generated?

Answer 18

Diploid oogonia enter meiosis and arrest in prophase 1 as primary oocytes

Question 19

When do primary oocytes start to mature?

Answer 19

In adults, after puberty

Question 20

When does meiosis 1 complete in oogenesis?

Answer 20

Complete just before ovulation

Question 21

What condition must be met for secondary oocytes to finish metaphase II?

Answer 21

Fertilisation

Question 22

When is the first polar body produced in oogenesis?

Answer 22

When Primary oocyte completes meiosis 1 just before ovulation

Question 23

When is the second polar body produced in oogenesis?

Answer 23

After fertilisation when meiosis 2 is completed

Question 24

What’s the function of beta-N-acetylglucosaminidase?

Answer 24

Digests N-acetylglucosamine residues from O-linked oligosaccharides on ZP3

Question 25

What’s the function of acrosin

Answer 25

Serine protease which lyses the Zona pellucida

Question 26

Function of CD9?

Answer 26

Facilitates structural changes for cytoplasmic fusion

Question 27

How does the Ca2+ influx cause the completion of meiosis II?

Answer 27

Ca2+ activates a kinase that leads to proteolysis of cyclin

Question 28

What did Driesch do?

Answer 28

Removed early embryo cells from sea urchins to show pre formation isn’t true and that cells retain developmental flexibility

Question 29

What did Wolff do?

Answer 29

Observed progressive tissue growth and differentiation in chick embryos to disprove pre formation