Cell Division - Meiosis

Question 1

What is the difference between gametes and normal cells?

Answer 1

Gametes have half the usual number of chromosomes

Question 2

Why do gametes only have one copy of each chromosome?

Answer 2

So that when the two sex cells combine they end up with the right number of chromosomes (46, 23 pairs)

Question 3

How does sexual reproduction produce variation?

Answer 3

The offspring has a mixture of two sets of chromosomes.

Question 4

Define meiosis.

Answer 4

Meiosis produces cells which have half the normal number of chromosomes.

Question 5

Describe the stage of first division in meiosis.

Answer 5

Chromosome pairs line up in the centre of the cell, the cells are then pulled apart so that each new cell only has one copy of each chromosome.

Question 6

Describe the stage of second division in meiosis.

Answer 6

• Again, the chromosomes line up in the centre of the cell, (similarly to mitosis) the arms of the chromosomes are pulled apart…
• You get four gametes each with only a single set of chromosomes