6.6 Reproduction Flashcards Preview

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Flashcards in 6.6 Reproduction Deck (14):
1

List 4 hormones in the menstrual cycle

FSH, Oestrogen, LH, Progesterone

2

State the source of FSH (follicle stimulating hormone)

Pituitary gland

3

Outline the function of FSH in the menstrual cycle

Stimulates follicular growth; stimulates oestrogen secretion (from developing follicles)

4

State the source of oestrogen

Developing follicles in the ovaries

5

Outline the function of oestrogen in the menstrual cycle

Development of endometrium; stimulates LH secretion (follicular phase); high levels inhibit LH and FSH (luteal phase)

6

State the source of LH (luteinising hormone)

Pituitary gland

7

Outline the function of LH in the menstrual cycle

Surge causes ovulation; development of corpus luteum; stimulates progesterone secretion

8

State the source of progesterone

Corpus luteum in the ovaries

9

Outline the function of progesterone in the menstrual cycle

Thickening of endometrium; high levels inhibit FHS and LH (luteal phase)

10

List three roles of testosterone in males

• Pre-natal development of male genitalia
• Development of secondary sexual characteristics
• Maintenance of sex drive

11

Outline the process of in vitro fertilisation (IVF)

1. Various drugs injected to stop the menstrual cycle.
2. Large doses of FSH injected to stimulate ovaries to develop many follicles.
3. HCG hormone injected causing the follicles to mature
4. Eggs removed from the ovaries and incubated at 37C
5. Sperm collected and screened
6. The healthiest sperm are selected and mixed with the eggs in a dish forcing fertilization.
7. Up to four embryos are selected and implanted in the uterus.
8. After a few weeks, a pregnancy test is administered.
9. Done in cases of low sperm count female infertility

12

List two reasons for IVF

• Infertility
• Low sperm count

13

List 2 advantages of IVF

• Chance for infertile couples to have children
• Genetic screening of embryos could reduce suffering from genetic disease

14

List 4 disadvantages of IVF

• Inherited, genetic forms of infertility could be passed onto children, going against natural selection
• Spare embryos are killed or donated to stem cell research
• Success rate is low ~15% and therefore stressful for couples
• Could lead to eugenics