Reproduction + hormones

Question 1

How is the female reproduction system adapted for its function?

Answer 1

Ovary - Contains ova (female gametes) which develop when FSH is released
Oviduct- Connects ovary to the uterus and is lined with ciliated cells that push the
ovum towards the uterus for fertilisation
Uterus - Has a thick lining so that fertilised eggs can be implanted
Cervix - Ring of muscle at lower end of uterus to ensure foetus remains in place
during pregnancy
Vagina - Muscular tube that leads to the inside of the body

Question 2

How is the male reproduction system adapted for its function?

Answer 2

Sex gland - Produces semen that contains sperm cells
Sperm duct - Sperm passes through this
Testis - Contained in scrotum (bag of skin) and produces sperm and testosterone
Penis - Passes urine and semen out of the body
Urethra - Tube inside the penis to carry urine or semen. A ring of muscle inside stops the two mixing.

Question 3

How are egg cells adapted to their

function?

Answer 3

• They are very large cells
• They contain a large cytoplasm for the
  lots of divisions they undergo
• They have a haploid nucleus

Question 4

How are sperm cells adapted to their

function?

Answer 4

- Acrosome contains enzymes so the sperm can
penetrate the egg
- Haploid nucleus
- Tail so that it can swim to the egg
- Lots of mitochondria for energy

Question 5

What role does oestrogen play during

puberty?

Answer 5

• Increases breast size
• Triggers the development of the uterus
• It causes eggs to mature during the
  menstrual cycle

Question 6

What role does testosterone play during

puberty?

Answer 6

- Triggers growth and development of the penis
and testes
- Causes the voice to deepen
- Triggers the growth of pubic hair
- Increases muscle mass

Question 7

On average how long is the menstrual cycle and on what day does ovulation occur?

Answer 7

The menstrual cycle last 28 days and the egg is usually released on day 14 (ovulation)

Question 8

What is the role of oestrogen in the menstrual cycle

Answer 8

● Oestrogen causes thickening of the uterus in
preparation for implantation of an egg
● Levels peak on day 10 and then begin to fall

Question 9

What is the role of progesterone in the menstrual cycle

Answer 9

● Progesterone maintains the thick lining of
uterus
● Inhibits the release of LH and FSH
● The egg matures on day 14 and progesterone
starts increasing after this until it reaches its
peak 3 days later. If the egg is not fertilised progesterone levels fall and the uterus lining breaks down in a period
that lasts for around 5 days

Question 10

What is the role of FSH in the menstrual cycle

Answer 10

FSH (follicle stimulating hormone) causes maturation of the egg within the ovary

Question 11

What is the role of LH in the menstrual cycle

Answer 11

LH (luteinizing hormone) stimulates the release of the egg during ovulation

Question 12

What causes an increase in LH and FSH

Answer 12

A decrease in oestrogen

Question 13

In terms of hormones when does ovulation happen

Answer 13

When LH and FSH levels peak

Question 14

What is the purpose of amniotic fluid?

Answer 14

To protect the developing fetus

Question 15

What is amniotic fluid?

Answer 15

Amniotic fluid is a liquid contained in a bag (amnion) in the uterus that surrounds the foetus. It
protects the foetus and cushions any rough movement

Question 16

What is the role of the placenta?

Answer 16

• To allow nutrients and oxygen to pass
  from the mother to the fetus during
  development.
• The placenta allows diffusion of glucose, oxygen and amino acids from the mother’s blood to the developing foetus for growth. Carbon dioxide and urea from the foetus are passed into the mother’s blood to be removed. It also takes over the production of progesterone.

Question 17

What is the placenta?

Answer 17

• The placenta is a large organ that develops during pregnancy. It is attached to the wall of the uterus, usually at the top or side. The umbilical cord connects the placenta to the developing foetus