A piece of DNA was cut using a restriction enzyme which produced fragments of the following sizes. 350 bp, 1300 bp and 1800 bp.
The fragments were then separated using gel electrophoresis. A molecular weight marker was loaded into lane 1 and the digest fragments were loaded into lane

2. a) The bands for the fragments of the molecular weight marker are shown in lane 1 (fragment sizes are known to be 500 bp, 1000 bp, 1500 bp and 2000 bp). Label the fragment sizes for these bands in base pairs (bp) on the blanks beside the gel.

b) On the gel, sketch the bands that would be produced by the digest fragments.

1) gene flow

- it is described as the transfer of genes from one population to another population so that frequency of gene is increased.

-a zebra migrates to join a different herd of zebras.

2) natural selection

- a mechanism of evolutionary change in which individuals with advantageous traits survive and reproduce whereas the others ( those that can not adapt) eliminate from the population.

-competition for sunlight leads to taller trees.

3) mutation

- permanent change in the nucleotide sequence of dna ( genetic material) that could have harmful or useful consequences.

-the dna of a snake changes to make its venom stronger.

4) genetic drift - it is a random phenomenon ( that occurs by chance such as fire) that results in change in the gene frequency in a small population.    

-a grassfire randomly sweeps through a population of buffalo and kills most of the animals.

explanation:

name and explain one of the event that occurs during meiosis that increases the variation in offspring even more than simple reproduction?