Life Goes On

Question 1

What are hormones released by

Answer 1

Endocrine glands

Question 2

What hormones are released by the ovaries

Answer 2

Oestrogen and progesterone

Question 3

What hormones are released by the testes

Answer 3

Testosterone

Question 4

An egg is released from one ovary each month

Describe the menstrual cycle

Answer 4

Uterus lining breaks down (period)
Uterus wall is repaired and thickens gradually
Egg is released from one ovary
Thick uterus lining (rich in blood vessels) awaits fertilised egg
If none are detected, cycle starts again

Question 5

Follicle-stimulating hormone (FSH)

Answer 5

Stimulates an egg to ripen in ovary

Question 6

What hormone does the ripening egg release

Answer 6

Oestrogen
Stimulates uterus lining to repair and thicken
And stimulates release of luteinising hormone (LH)

Question 7

Luteinising hormone (LH)

Answer 7

Controls ovulation (release of egg) about halfway through the menstrual cycle

Question 8

Where are FSH and LH released from

Answer 8

Pituitary glad in brain

Question 9

After ovulation, what is produced

Answer 9

Progesterone is produced by the ovary to maintain uterus lining

Question 10

What occurs as oestrogen and progesterone levels fall towards the end of the cycle

Answer 10

Menstruation

Question 11

What sort of loop do the hormones governing the menstrual cycle operate in

Answer 11

Negative feedback loop

Question 12

How can fertility in women be restricted artificially

Answer 12

Contraceptive pills- hormones prevent release of eggs from the ovaries
They do this by mimicking pregnancy involving inhibition of FSH release

Question 13

Infertility treatments increase chance of fertility

Answer 13

Fertility drug- FSH injected to stimulate eggs to ripen and release if woman does not produce enough FSH
Artificial insemination- If sperm count is low, blocked ducts or oviducts. Sperm injected uterus/oviducts
IVF- sperm and eggs mixed outside body (glass dish). Successful embryo transplanted into uterus
Donation- sperm or eggs, IVF can then be used
Ovary transplant- supplied eggs if own ovaries do not function
Surrogate- IVF embryo transplanted in woman who carries it

Question 14

Disadvantages of IVF

Answer 14

Very expensive with fairly low success rate

Often several attempts needed for viable embryo

Question 15

Disadvantages of Sperm/egg donation

Answer 15

Embryo carries genes from one parent with the other from the donor

Question 16

Disadvantages of surrogate mothers

Answer 16

May become emotionally attached and find adoption difficult

Question 17

Negative effect of contraceptive pill

Answer 17

Can reduce fertility through use of female hormones that prevent ovulation
They do this by mimicking pregnancy involving inhibition of FSH release

Question 18

Foetal screening (to monitor progress)

Answer 18

Ultrasound- reveal baby’s sex, multiple pregnancies or developmental defects early in pregnancy

Amniocentesis- A hypodermic needle takes amniotic fluid and cell sample from foetus which are checked for chromosome abnormalities such as Down’s Syndrome

Question 19

Ethics of amniocentesis

Answer 19

Risk of miscarriage (1 in 200)
If test is positive, parents have to make the decision whether to abort or continue with pregnancy
Some argue it gives option to end a life

Question 20

Why is scrotum outside of the body

Answer 20

To keep testes (produce sperm) at a lower temperature for better sperm development

Question 21

What are hormones

Answer 21

Chemicals released directly into the bloodstream and travel around the body to their target organs