Cell Division

Question 1

Chromosomes are found in….

Answer 1

Pairs

Question 2

D. Meiosis

Answer 2

2 stage process of cell division that reduces the chromosomes of daughter cells. It is involves in making gametes for sexual reproduction

Question 3

How many chromosomes do you have?

Answer 3

46 - 23 pairs

Question 4

Stages of the cell cycle:

Answer 4

1: longest. Grows bigger-increases mass, replicate DNA form 2 copies of each chromosome. Increase number of sub-cellular structures (eg. Mitochondria)
2: mitosis - each set of chromosomes are pulled to a different end of cell = nucleus divides.
3: cytoplasm and cell membranes divide to form 2 identical daughter cells.

Question 5

When do most types of animal cells differentiate?

Answer 5

At an early stage of development.

Question 6

D. Differentiation.

Answer 6

The process where cells become specialised for a certain function.

Question 7

D. Zygote?

Answer 7

When the egg and sperm fuse.

Question 8

2 types do stem cells?

Answer 8

Embryonic and adult

Question 9

Where are adult stem cells from?

Answer 9

Bone marrow

Question 10

Uses of stem cells in humans?

Answer 10

• Treatment of paralysis and spinal injuries
• Treatment of diabetes
• Restoration of eyesight
• Bone damage and cartilage
• Heart damage after a heart attack

Question 11

Uses of stem cells in plants?

Answer 11

• Clones of the mature plant can be grown very quickly and economically
• Large numbers of rare plants can be produced - save from extinction?
• Produce large quantities of cloned plants with disease resistance

Question 12

Problems with embryonic stem cells?

Answer 12

• Most come from aborted embryos or spare embryos from fertility treatment
• As embryo cannot give permission it’s a violation of human rights
• Developments are slow, expensive and hard to control
• May cause cancer
• Trigger an immune response

Question 13

How are scientists overcoming ethical issues with embryonic stem cells?

Answer 13

Taking them from the umbilical cord and amniotic fluid.

Question 14

Advantages of embryonic stem cells? (4)

Answer 14

• Wont be rejected by patient
• Many cells can be produced
• reduce waiting time for organ transplants
• Cells and tissues of any type could be produced

Question 15

D. Allele?

Answer 15

a version of a particular gene

Question 16

D. Cytokinesis?

Answer 16

the dividing of the cell at the last stage of mitosis

Question 17

D. Chromosome?

Answer 17

a thread-like structure carrying genetic material

Question 18

D. Mitosis?

Answer 18

Asexual cell division where 2 identical cells are formed

Question 19

D. Chrimatids?

Answer 19

duplicate chromosomes produced during mitosis