6.6 - Reproduction

Question 1

6.6.2 - The role of FSH in the menstrual cycle

Answer 1

FSH - Follicle Stimulating Hormone

• *Secreted from:**
• Anterior Pituitary
• *Function:**
• Stimulates follicular growth
• Stimulates estrogen secretion (from developing follicles)

Question 2

6.6.2 - The role of LH in the menstrual cycle

Answer 2

LH - Luteinising Hormone

• *Secreted from:**
• Anterior pituitary
• *Function:**
• Surge causes ovulation
• Development of corpus luteum
• Stimulates progesterone secretion

Question 3

6.6.2 - The role of estrogen in the menstrual cycle

Answer 3

Estrogen

• *Secreted from:**
• Ovaries (developing follicle)
• *Function:**
• Development of endometrium
• Stimulates LH secretion (follicular phase)
• Inhibits LH and FSH (luteal phase)

Question 4

6.6.2 - The role of progesterone in the menstrual cycle

Answer 4

Progesterone

• *Secreted from:**
• Ovaries (corpus luteum)
• *Function:**
• Thickening of endomentrium
• Inhibits LH and FSH (luteal phase)

Question 5

6.6.4 - List three roles of testosterone in males

Answer 5

1. Pre-natal development of male genetalia
2. Development of secondary sex characteristic
3. Maintenance of sex drive (libido)

Question 6

6.6.5 - Outline the process of in vitro fertilisation

Answer 6

Refers to fertilisation outside of the body (“in vitro”=”in glass”)

• Stop menstrual cycle (with drugs
• Hormone treatment to develop follicles (FSH to stimulate follicle growth ; hCG for follicle maturation)
• Extract multiple eggs from ovaries
• Sperm selected, prepared (capacitation) and then injected into egg via intra-cytoplasmic sperm injection (ICSI)
• Fertilisation occurs in glass (in vitro)
• Implantation of embryos into uterus
• Test for pregnancy is conducted to see if implantation was successful

Question 7

What is a follicle?

Answer 7

Fluid filled sac containing an egg cell

Question 8

6.6.6 - Discuss the ethical issues associated with IVF

Answer 8

• *Advantages**
• Chance for infertile couples to have children
• Genetic screening of embryos could decrease suffering from genetic diseases
• Spare embryos can be stored for future pregnancies or used for stem cell research

Disadvantages of IVF
- IVF is expensive and might not be equally accessible to all
- Success rate is low (~15%) and therefore stressful for couples
- It could lead to eugenics (e.g. gender choice)
Often leads to multiple pregnancies which may be unwanted, unable to be budgeted for and involves extra birth risks
- Issues concerning storage and disposal of unused embryos (right to life concerns)
- There are cultural and religious objections to embryo creation by such means
- Inherited forms of infertility may be passed on to children