crossing over

Question 1

Crossing over is the process by which

Answer 1

non sister chromatids exchange alleles

Question 2

Process:
During meiosis I homologous chromosomes pair up and are in very close proximity to each other

The non-sister chromatids can ………………

These crossing points are called ……………..

The entanglement places ……….on the DNA molecules

As a result of this a section of chromatid from one chromosome may break and

Answer 2

cross over and get entangled

chiasmata

stress

rejoin with the chromatid from the other chromosome

Question 3

This swapping of alleles is significant as it can result in a

Answer 3

new combination of alleles on the two chromosomes

Question 4

There is usually at least one, if not more, chiasmata present in each bivalent during meiosis
Crossing over is more likely to occur

Answer 4

further down the chromosome away from the centromere