Meiosis

Question 1

Haploid

Answer 1

Only contain one copy of each chromosome in a homologous pair (eg. Gametes)

Question 2

Homologous pairs

Answer 2

Pairs of matching chromosomes that carry the same genes but different alleles

Question 3

Fertilisation

Answer 3

Gametes fuse (haploid sperm fuses with a haploid egg cell) forming a diploid zygote

Question 4

Where does meiosis take place?

Answer 4

In the reproductive organs of multicellular, eukaryotic organisms

Question 5

Meiosis process

Answer 5

1) DNA unravels and replicates
2) DNA condenses to form double-chromosomes, each made from two sister chromatids, joined by a centromere
3) In the first division homologous pairs separate, halving chromosome number
4) In the second division pairs of sister chromatids separate and the centromere divides
5) Four genetically different haploid cells produced

Question 6

Which events during mitosis lead to genetic variation?

Answer 6

Crossing over of chromatids and independent segregation of chromosomes

Question 7

Crossing over of chromatids

Answer 7

During meiosis I, homologous chromosomes pair up, twist around and swap alleles. So each daughter cell has different chromatids

Question 8

Independent segregation of chromosomes

Answer 8

When the homologous pairs are separated in meiosis I, it’s random which chromosome from each pair ends up in which daughter cell. So each daughter cell has different combinations of maternal and paternal chromosomes