Human Reproduction

Question 1

Testes

Answer 1

Where sperm are formed and testosterone is produced

Question 2

Scrotum

Answer 2

Holds testes outside the body as the optimum temp. of sperm production is 34°C (whereas core body temp. is 37°C

Question 3

Urethra

Answer 3

Tube which sperm (and urine) leave the penis

Question 4

Seminal Vesicle

Answer 4

Provides fluid rich in fructose for energy, and contains protective mucus
Makes up 70% of semen.
Secreted into sperm duct and mixed with sperm to produce semen.

Question 5

Erectile Tissue

Answer 5

Fills with blood during an erection, causing penis to stiffen in order to be inserted into the vagina during sexual intercourse

Question 6

Sperm Duct

Answer 6

Tube connecting testes to the urethra and through which mature sperm travel

Question 7

Ovary

Answer 7

Structure in which ova develop in structures called follicles.
Secrete oestrogen at different points during the menstrual cycle

Question 8

Fallopian Tube

Answer 8

Tube through which ova travel to reach uterus

Question 9

Uterus

Answer 9

Muscular wall where the early embryo implants after fertilization. Placenta attaches to this.
Contracts during childbirth to push baby out.
Lining is shed every month

Question 10

Cervix

Answer 10

A narrowing of the uterus which leads to the vagina.
Enlarges greatly during labor to allow passage of the fetus

Question 11

Vagina

Answer 11

Passageway leading from the uterus to the outside
Sperm is deposited here during compilation and the fetus is born through it

Question 12

Sperm

Answer 12

Male gamete. Has acrosome head with enzymes to penetrate ovum.
Has flagellum to swim up the oviduct. Contains many mitochondria to release energy for movement.

Question 13

Ova

Answer 13

Female gamete. Has a large cytoplasm as a food store for the developing embryo.

Question 14

Penis

Answer 14

Structure which transfers sperm from male to female during sexual intercourse.

Question 15

Oestrogen

Answer 15

Secreted by the follicle in response to FSH
Causes thickening of the uterus lining
Stimulates secretion of LH

Question 16

Progesterone

Answer 16

Produced by the corpus luteum (after ovulation)
Completes development of uterus lining
Stops FSH and LH secretion to stop further ovulation

Question 17

FSH (Follicle Stimulating Hormone)

Answer 17

Released from pituitary gland in the brain
Causes egg cell in ovary to mature

Question 18

LH (Lutenising Hormone)

Answer 18

Released from pituitary gland in the brain
Causes ovulation

Question 19

Ovulation definition

Answer 19

The release of a mature egg cell (ovum) into the oviduct

Question 20

Menstruation definition

Answer 20

The break down and shedding of the uterus lining in preparation for a new egg cell

Question 21

Menstrual Cycle (5 parts)

Answer 21

Day 1-5: Menstruation. FSH levels rise, stimulating secretion of ovulation
Day 6-13: New uterus lining develops. New ovum matures in ovary. Oestrogen levels rise stimulating secretion of LH
Day 14: LH peaks. Ovulation
Day 18-19: Ovum travels through oviduct to uterus. Blood supply develops into new uterus lining. Progesterone levels rise, developing and maintaining uterus lining.
Day 20-28: Ovum dies if not fertilised. Progesterone levels drop, causing degeneration of the uterus lining.

Question 22

Oestrogen in puberty

Answer 22

Stimulates secondary sexual characteristics in women
-Beginning of menstruation
-Increase in body mass (rounded hips)
-Breast development

Question 23

Testosterone in puberty

Answer 23

Sperm production starts
Growth of facial hair and body hair
Growth of penis and testes
Muscle development
Breaking of voice

Question 24

Amniotic fluid function:

Answer 24

Embryo enclosed within amnion membrane
Protects fetus against against jolts and bumps
Ruptures during childbirth (water breaks)

Question 25

Role of placenta

Answer 25

Exchange substances between mother’s blood and blood of fetus
Large s.f. and thin wall (for faster diffusion)
Barrier against toxins and pathogens(not viruses)