B2 - Cell Division

Question 1

How many chromosomes pairs are there in the human body

Answer 1

23 pairs

Question 2

What is the process cells do to divide?

Answer 2

Mitosis

Question 3

What is stage 1 of mitosis?

Answer 3

DNA replicates to form two copies of each chromosome. It also grows in size and replicates internal structures such as mitochondria and ribosomes

Question 4

What happens in stage 2 of mitosis?

Answer 4

Mitosis happens. This is when the cell divides with one set of each chromosome

Question 5

What happens in the final stage of mitosis/

Answer 5

The cell wall and cytoplasm divide to create 2 identical cells

Question 6

What is the function of mitosis? Name examples

Answer 6

It is essential for the growth and development of multicellular organisms like plants and animals
When a bone is broken it helps to heal the organism
And during asexual reproduction

Question 7

When a fertilised ovum undergoes mitosis what does it become?

Answer 7

A ball of cells known as a embryo

Question 8

When the embryo cell changes what is this known as?

Answer 8

Differentiation

Question 9

Where else are stem cells found?

Answer 9

Bone marrow

Question 10

What can the stem cells found in bone marrow differentiate into?

Answer 10

They change to become platelets ,red and white blood cells

Question 11

Explain how bone marrow can help someone who has leukemia

Answer 11

Leukemia is cancer of the bone marrow. First the existing bone marrow is destroyed by radiation (chemotherapy). Then a donor gives new bone to which it then divides by mitosis to create new bone marrow, and differentiates to form new blood cells

Question 12

What is a reason to why someone might be against the use of stem cells?

Answer 12

Embryos can not give consent to have their cells used which is a violation of human rights. Also someone of a religious background might not believe in interfering in the process of human reproduction