B2 Cell Division

Question 1

What are stem cells

Answer 1

A stem cell is an undifferentiated cell which could turn into any cell in an organism

Question 2

What are the 2 main properties of stem cells

Answer 2

• can divide by mitosis indefinitely
• can differentiate into specialised cells

Question 3

What are the 2 types of stem cells

Answer 3

Embryonic and adult

Question 4

What are the features of embryonic stem cells

Answer 4

• early stage of the embryo
• can produce any type of cell

Question 5

What are the features of adult stem cells

Answer 5

These cells can grow and replace SIMILAR damaged cells ( eg. Blood cells from bone marrow)

Question 6

What is meristem

Answer 6

This is a type of stem cell in plants that help them differentiate into any type of plant cell thought the plants life ( this Is how they are able to grow after being cut down)

Question 7

What is theraputic cloning

Answer 7

Producing an embryo with the same genes as a patient

Question 8

What are the stages of therapeutic cloning

Answer 8

• combining a egg cell without nucleus and nucleus from a patient
• shock to start
• after time an embryo is created
• stem cells are removed from embryo and signalled to create any animal cell

Question 9

Why does cell division take place

Answer 9

• G rowth
• R epair
• R eplace

Question 10

What are the 3 stages to the cell cycle

Answer 10

1. DNA is replicated
2. Mitosis- the nucleus divides
3. Cytoplasm and cell membranes divide to from 2 identical cells

Question 11

What are the stages of mitosis

Answer 11

1. DNA replicates so you have 2 copies of
   each chromosome.
2. Pairs of chromosomes start to line up
   in the middle of the cell.
3. Spindle fibres attach to centre of each
   pair of chromosomes
4. 1 copy of each chromosome is pulled
   to opposite poles of the cell.
5. Two new identical daughter cells form
   containing the same DNA as the original