Which is a reflex response?

Answer/ explanation :

Reflex response is an involuntary, automatic and rapid response to a stimulus.

It's is controlled by the brain stem.

Reflex actions cannot be controlled. They are coordinated by nerves which moves to and fro in the spinal cord without a direct involvement of the brain.

Examples of a reflex response

Sneezing, coughing, yawning, toughing a hot object, blinking of the eyes.

There are two types of reflex response

Autonomic reflex arc

The somatic reflex arc

The reflex responses happens so quickly because they do not have to be processed by the brain before taking place.

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: