Division and differentiation in human cells

Question 1

What is a somatic cell?

Answer 1

Any cell in the body other than the cells involved in reproduction.

Question 2

How do somatic cells divide?

Answer 2

Divide by mitosis

Question 3

What are germline cells?

Answer 3

They are gametes and stem cells that divide to form gametes

Question 4

How do germline cells divide?

Answer 4

Divide by mitosis to produce more gremlin cells and then by meiosis to produce haploid gametes

Question 5

How many chromosomes does a haploid gamete contain?

Answer 5

23 single chromosomes.

Question 6

What is cellular differentiation?

Answer 6

process by which a cell express certain genes to produce proteins characteristics for that type of cell. This allows the cell to carry out specialised functions.

Question 7

What are the two types of stem cell?

Answer 7

• Embryonic stem cells
• Tissue (adult) stem cells

Question 8

Describe an embryonic stem cell:

Answer 8

All the genes in an embryonic stem cell can be switched on, so these types of cells can differentiate into any cell type. They are pluripotent.

Question 9

Describe a tissue (adult) stem cell:

Answer 9

Tissue stem cells are involved in the repair, growth and renewal of cells found in a particular tissue. They can differentiate into all the types of cell found in a particular tissue type. They are multipoint.

Question 10

Name examples of the therapeutic use of stem cells?

Answer 10

1. corneal repair
2. regeneration of damaged skin

Question 11

Name an example of the research of stem cells?

Answer 11

• Drug testing

Question 12

How is a tumour formed?

Answer 12

The cancer cells divide excessively because they do not respond to regulatory signals, results in a mass of abnormal cells which is called a tumour.

Question 13

How do secondary tumours form?

Answer 13

The cells fail to attach to each other and spread elsewhere in the body.