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Flashcards in Gamete formation Deck (10)
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1
Q

Which are the only cell found in the body that can undergo both meiosis and mitosis?

A

Primordial germ cells

2
Q

What do Primordial germ cells produce?

A

Sperm/Eggs

3
Q

Talk through oogenesis

(6 stages) Which stages are before birth/after puberty?

A

Before birth:

1) Primordial germ cells undergo mitosis
2) PMCs differentiate into oogonia in gonad and continue mitosis - some into meiosis I
3) Arrest as primary oocytes in prophase I

After puberty:

1) Continues meiosis I = secondary oocyte and polar body
2) Begins meiosis II - arrests in metaphase II
3) Completes meiosis on fertilisation - 1 or 3 more polar bodies.

4
Q

When is meiosis of female gametes complete? In which two places of oogenesis does meiosis arrest?

A

Only on fertilisation by sperm.

Arrests in prophase I at birth until puberty- primary oocytes.

After puberty - Arrests in metaphase II as secondary oocyte - until fertilised - meiosis completes

5
Q

What is a primordial follicle?

A

A primary oocyte surrounded by flattened epithelial cells

6
Q

What is a primordial follicle?

A

A primary oocyte surrounded by flattened epithelial cells

7
Q

Do PGCs differentiate in men before puberty?

A

No spermatogenesis only occurs at puberty

8
Q

Do PGCs differentiate in men before puberty?

A

No spermatogenesis only occurs at puberty

9
Q

Do male or female gametes experience more mutations?

A

Male as much more mitosis/meiosis.

10
Q

What is the most common cause of miscarriage?

A

Chromosomal abnormality in gamete