Meiosis

Question 1

what is the role meiosis

Answer 1

it makes gametes with only half the original number of chromosomes

Question 2

Where does meiosis occur in humans?

Answer 2

in the reproductive organs (the ovaries in females and testes in males)

Question 3

How does meiosis work?

Answer 3

1)Before the cell starts to divide, it duplicates its genetic information, forming two armed chromosomes — one arm of each chromosome is an exact copy of the other arm. After replication, the chromosomes arrange themselves into pairs.
2)In the first division in meiosis the chromosome pairs line up in the centre of the cell.
3)The pairs are then pulled apart so each new cell only has one copy of each chromosome. Some of the father’s chromosomes and some of the mother’s chromosomes go into each new cell.
4)In the second division, the chromosomes line up again in the centre of the cell. The arms of the chromosomes are pulled apart.
5)You get four gametes, each with only a single set of chromosomes in it. Each of the gametes is genetically different from the othersbut they all have 23 chromosomes

Question 4

What happens after the 2 gametes combine during fertilisation?

Answer 4

-the resulting new cell divides by mitosis to make a copy of itself
-mitosis repeats many times to produce lots of new cells in an embryo
-as the embryo develops these cells then start to differentiate into different types of specialised cell that make up whole organism