Stem Cells

Question 1

How many sets of chromosomes do somatic cells have and what does this mean?

Answer 1

2, this means they are diploid cells

Question 2

What do somatic cells divide by?

Answer 2

Mitosis

Question 3

During mitosis, why does the nucleus of a somatic cell divide?

Answer 3

To maintain the diploid chromosome number

Question 4

Human diploid cells have how many pairs of homologous chromosomes?

Answer 4

23 pairs

Question 5

What are germline cells called in humans?

Answer 5

Gamete mother cells

Question 6

What can the nucleus of a germline cell divide by?

Answer 6

Mitosis or meiosis

Question 7

What are adult stem cells involved in?

Answer 7

Growth, repair and renewal of cells found in that tissue

Question 8

What are the main body tissue types?

Answer 8

Epithelial, connective, muscle and nerve

Question 9

What do multipotent haematopoietic stem cells in the red blood marrow do?
Give examples

Answer 9

Give rise to all the cell types in the blood, e.g red blood cells, platelets and various forms of phagocytes and lymphocytes

Question 10

Why can embryonic stem cells differentiate into any type of human cell?

Answer 10

Because most of their genes are still switched on (expressed)

Question 11

Adult stem cells can only produce a limited range of cell types, what does this mean?

Answer 11

This means they are multipotent

Question 12

What does stem cell research provide information about?

Answer 12

Cell growth
Differentiation
Gene regulation

Question 13

What can stem cells be used as?

Answer 13

Can be used as model cells to study how diseases develop or for drug testing

Question 14

What are the therapeutic uses for stem cells?

Answer 14

Bone marrow transplants - ie treatment of leukaemia
Skin grafts for burns
Repair of damaged or diseased organs (or tissues)

Question 15

What causes cancer cells to divide excessively?

Answer 15

Cancer cells do not respond to signals that regulate them

Question 16

What happens when cancer cells fail to attach to each other?

Answer 16

They can spread throughout the body where they form secondary tumours

Question 17

Where do most cancers starts from?

Answer 17

Start from cells that have undergone a series of mutations to the gene involved in the control of cell division

Question 18

What are the agents that cause genetic damage?

Answer 18

Smoking
Pollution
Excessive skin exposure to UV light
Mustard gas

Question 19

What are somatic cells?

Give examples

Answer 19

Non sex cells, e.g. Skin, muscle, bone and blood