When blood glucose levels are high View Available Hint(s) When blood glucose levels are high The pancreas releases insulin. The pancreas releases glucose. The liver releases insulin. The pancreas releases glucagon. The liver releases glucagon.

Explanation:

Pancreas release both insulin as well as glucagon, but there release depends on different glucose levels in bloodstream. When blood glucose concentration increases, in response to it Insulin is released by the beta cells in the islets of Langerhans.

Role of insulin: i) it lower glucose levels in the bloodstream, ii) it also promote the storage of glucose in muscle, liver and other parts o the body .

While  alpha cells in the islets of Langerhans produce glucagon when glucose concentration decreases in the blood.

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: