Module 2 Animal Reproduction

Question 1

What is puberty?

Answer 1

When humans become sexually mature, happens when we are teenagers.

Question 2

What are gametes?

Answer 2

sex cells

Question 3

Give 5 changes that happen to males at puberty.

Answer 3

1. hair grows under the arms, in the pubic region, on the face and chest. 2. voice breaks as the voice box enlarges. 3. penis becomes larger 4. muscles develop and shoulders get wider. 5. testes start to produce sperm

Question 4

Give 5 changes that happen to females at puberty.

Answer 4

1. hair grows under the arms and in the pubic region 2. hips widen 3. breasts grow and develop. 4. periods begin 5. ovaries start to release eggs

Question 5

How is puberty started?

Answer 5

Chemicals called sex hormones, produced by the ovaries in girls and the testes in boys.

Question 6

At what age does puberty start?

Answer 6

Boys: 12-16 Girls: 10-14

Question 7

1. Choose two ages when girls have a growth spurt and explain how you arrived at the answer.
2. Choose one age when girls and boys grow at the same rate.
3. Approximately how much taller do boys grow compared to girls

Answer 7

1. 4-6 and 10-12, shown by the steep parts of the graph
2. 4-6
3. 15 cm

Question 8

Testes

Answer 8

There are 2 which make the sperm

Question 9

scrotal sac

Answer 9

Contains the testes and lie outside the body as sperm need a slightly lower temperature (35 oC) than body temperature to develop normally

Question 10

sperm duct

Answer 10

leads from each testes to a point just below the bladder where it joins the urethra

Question 11

urethra

Answer 11

runs down the centre of the penis and carries both sperm and urine, but never at the same time

Question 12

prostrate gland

Answer 12

along with other glands, produces a liquid called semen for the sperm to swim

Question 13

penis

Answer 13

transfers sperm from the male to the female

Question 14

foreskin

Answer 14

protective covering of the penis

Question 15

Label the diagram of the male reproductive system

Answer 15

a) scrotal sac etc…

Question 16

Ovaries

Answer 16

the 2 ovaries make and release eggs (ova), at least 1 every month

also make female hormones

Question 17

oviduct

Answer 17

tube connecting oviducts to uterus, ova travels along it and is fertilised here

Question 18

uterus

Answer 18

womb, triangular shaped structure capable of great expansion

Question 19

cervix

Answer 19

tight neck of the uterus

Question 20

vagina

Answer 20

muscular tube connects uterus to outside

Question 21

sexual intercourse

Answer 21

when the penis is inserted into the vagina to pass sperm into the female body

Question 22

Label the diagram of the female reproductive system

Answer 22

a) ovary etc….

Question 23

(a) Both male and female systems have reproductive organs which occur in pairs. Can you think of any other organs in the body, which occur in pairs?
(b) Can you suggest a reason why many of the body’s organs are in pairs?

Answer 23

(a) Eyes, ears; lungs; kidneys
(b) If one becomes diseased or damaged, the function can still be carried out by the other remaining organ.

Question 24

Draw and label a diagram of a sperm cell

Answer 24

Question 25

Draw and label diagram of an egg cell

Answer 25

Question 26

Describe the journey of the sperm to the egg in the female

Answer 26

Sperm swim through the cervix into the uterus and then on to the oviducts. Many sperm will die, but as there are millions of sperm released, there is an increased chance of one healthy sperm meeting an egg and fertilising it.

Question 27

What happens once a sperm has broken through the cell membrane

Answer 27

The egg cell membrane hardens and keeps all the other sperm out.

The sperm nucleus passes into the egg and joins with the egg nucleus.

The fertilised egg now contains information from both the mother and the father.

As the fertilised egg continues its journey it divides into two and these two devide into two etc until a ball of cells is formed.

Question 28

label the diagram

Answer 28

Question 29

What happens when the ball of cells arrives in the uterus?

Answer 29

It sinks into the thick spongy lining. This is called implantation and the mother is now pregnant.

This ball of cells will continue to grow into a foetus. The foetus is not called a baby until it is born.

Question 30

amnion

Answer 30

thin skin surrounding the foetus

Question 31

amniotic fluid

Answer 31

the liquid that fills the amnion, it cushions and protects the baby from any bumps or knocks

Question 32

How long does pregnancy last?

Answer 32

40 weeks

Question 33

Label the diagram

Answer 33

Question 34

Answer 34

Question 35

What chemicals need to pass from the mother’s blood to the baby’s blood?

Answer 35

food and oxygen

Question 36

What chemicals need to pass from the baby’s blood to the mother’s blood?

Answer 36

waste and carbon dioxide

Question 37

Why do you think it is so important that the blood of the foetus and mother do not mix?

Answer 37

Mother and baby could belong to a different blood group. The presence of the mothers blood is much higher than the baby’s blood

Question 38

It is very important that the mother takes good care of herself during pregnancy. She should eat a healthy ___diet__ and not drink alcohol or _smoke_.
Why is this so important?

Answer 38

The developing baby gets all its food from the mother’s blood. It needs protein for growth, calcium for growing bones etc. The mother shouldn’t drink or smoke as the alcohol and the nicotine from the cigarette smoke can get across the placenta and harm the baby.