Sexual reproduction

Question 1

What is internal fertilisation?

Answer 1

This is the union of an egg cell and sperm cell, which occurs inside a woman.

Question 2

What is external fertilisation?

Answer 2

This is when a sperm cell fertilises an egg cell outside of the female’s body.

Question 3

What is a gamete?

Answer 3

This is a cell whose nucleus join with another cell to form a new organism.

Question 4

How many sperm make it to the egg?

Answer 4

Around 36.

Question 5

How many sperm cells are originally released?

Answer 5

300 million.

Question 6

What happens to the majority of sperm?

Answer 6

They die because they get trapped/caught in cilia or they might die in acid.

Question 7

How many chromosomes does each sex cell (sperm or egg) have ?

Answer 7

23.

Question 8

What is describes as ‘the beginning of a new human’?

Answer 8

Fertilisation-sperm and egg combine to make a zygote.

Question 9

Whats is sexual reproduction?

Answer 9

When an offspring is created by two parents.

Question 10

Name 3 features that makes sperm cells suits its function.

Answer 10

• Long tail
• No food store
• Pointy head
• Millions made each day

Question 11

Name 3 features that makes egg cells suits its function.

Answer 11

-Has a membrane so only 1 sperm can enter.
-Its large.
-Can’t move much.
1 or 2 made per month.

Question 12

What is amniotic fluid?

Answer 12

A watery substance surrounded around the body, serves as a layer of protection.

Question 13

What is an amnion?

Answer 13

A bag containing amniotic fluid.

Question 14

What is a placenta connected to?

Answer 14

Mother’s uterus.

Question 15

What is waste materials?

Answer 15

Things like carbon dioxide that are waste products of respiration.

Question 16

What is the name of the zygote when it is 100 cells big?

Answer 16

Blastocyst.

Question 17

When does the first splitting of identical twins start?

Answer 17

First week.

Question 18

What happens if the splitting of identical twins occurs earlier?

Answer 18

They develop more independently.

Question 19

If a cell divides later, what three features do they share?

Answer 19

Amnion, chorion and placenta.

Question 20

What is another name for non-identical twins?

Answer 20

Fraternal twins.

Question 21

Can non-identical twins share a placenta.

Answer 21

No, both babies do not share the same features.

Question 22

Name 6 things that happen when males grow up.

Answer 22

• Testes and penis gets bigger.
• Testes produce sperm.
• Voice breaks.
• Hair growth on face and chest.
• Shoulders get wider.

Question 23

Name things that both genders have when they grow up.

Answer 23

• Underarm hair.
• Body odour stronger.
• Growth rate increases.
• Mood swings.
• Pubic hair.

Question 24

Name 6 things that happen when females grow up.

Answer 24

• Breasts develop.
• Hips get wider.
• Ovaries start to release egg cells.

Question 25

What is ejaculation?

Answer 25

When semen(sperm cells mixed with special liquids from the glands) is forced out of the penis and into the top of the vagina.

Question 26

What happens to a fertilised egg cell?

Answer 26

It divides to form a ball of cells (an embryo).