Lab 11 (part 2 of 2) - Reproductive Physiology Flashcards Preview

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Flashcards in Lab 11 (part 2 of 2) - Reproductive Physiology Deck (16):
1

When does oogenesis begin?

Before birth

2

Explain:

Oogenesis before birth

- Oogonia (2n) in female fetal ovary goes through mitosis many times

- This produces over 2 million primary oocytes (2n)

- The primary oocytes become encapsulated by 1 layer of squamous-like cells

- They are then called primordial follicles

- Arrested at Prophase I

3

Explain:

Oogenesis at childhood

- Ovary is inactive

- Primary oocyte is arrested at Prophase I

4

Oogenesis (every 28 days) at puberty through menopause:

What happens first?

___ ___ matures and grows (due to ___ secretion) to become a ___ ___.

PRIMARY FOLLICLE

matures and grows (due to FSH secretion) to become a

SECONDARY FOLLICLE.

5

What happens to the 3 polar bodies during oogenesis from puberty until menopause?

They break down and die and get reabsorbed in the body.

6

Oogenesis (every 28 days) at puberty through menopause:

What happens second?

The ___ ___ finishes Meiosis ___ to produce 2 cells:

1) ___ ___

2) ___ ___

The PRIMARY OOCYTE (2n) finishes Meiosis I to produce 2 cells:

1) SECONDARY OOCYTE (n)
- has the most cytoplasm

2) POLAR BODY (n)

7

Concerning oogenesis from puberty until menopause, what happens to the secondary oocyte if it is not fertilized?

The secondary oocyte remains arrested in Metaphase II with 46 chromosomes.

8

Oogenesis (every 28 days) at puberty through menopause:

What happens third? (part 1/2)

The ___ ___ matures to become a ___ ___.

The SECONDARY OOCYTE

matures to become a

VESICULAR (GRAAFIAN, ANTRAL) FOLLICLE.

9

Oogenesis (every 28 days) at puberty through menopause:

What happens third? (part 2/2)

[The SECONDARY OOCYTE matures to become a VESICULAR (GRAAFIAN, ANTRAL) FOLLICLE.]

The follicle is arrested in ___ ___, unless fertilized by sperm.

If fertilized, a(n) ___ is produced.

The follicle is arrested in METAPHASE II, unless fertilized by sperm.

If fertilized, an OVUM is produced.

10

Oogenesis (every 28 days) at puberty through menopause:

What happens fourth?

The ___ ___ completes ___ ___ (regardless of fertilization by sperm) to produce 2 ___ ___, which disintegrate.

The POLAR BODY (n) completes MEIOSIS II

(regardless of fertilization by sperm)

to produce 2 POLAR BODIES (n), which disintegrate.

11

Explain:

Oogenesis once ovulation occurs

The ruptured follicle becomes corpus luteum (secretes progesterone and estrogen),

which eventually disintegrates into corpus albicans (scar tissue).

12

Contrast the products of spermatogenesis and oogenesis.

Spermatogenesis:
- Produces 4 haploid gametes (little cytoplasm, motile)

Oogenesis:
- Produces 1 haploid gamete (a lot of cytoplasm, nonmotile)

13

Explain:

Menstrual cycle at menstrual phase

- Day 1 - 5

- Sloughing of endometrium (bleeding)

- Results from decline in estrogen and progesterone

14

Explain:

Menstrual cycle at proliferative phase

- Day 6 - 14

- Repair/thickening of endometrium

- Glands and blood vessels proliferate

- Estrogen increases up to about Day 14 when ovulation occurs: secondary oocyte ovulates

- Ovulation triggered by luteal (LH) surge!

15

Explain:

Menstrual cycle at secretory phase

- Day 15 - 28

- Glands and blood vessels proliferate

- Glands secrete nutrients for "embryo"

- Corpus luteum secretes more progesterone

16

Regardless of length of menstrual phase of the menstrual cycle, ovulation always occurs around Day ___.

Day 14