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Amylase is the enzyme that controls the breakdown of starch to glucose. Describe how the student could investigate the effect of pH on the breakdown of starch by amylase.

Breakdown answer into 5 simple marks that can be easily understood and remembered:Control variable - Keep amount of amylase and starch the sameDependent Variables - change PH levels 3 times Keep temperatu...

Answered by Kitty P. • Biology tutor

11508 Views

If a gene mutation is associated with the development of Alzheimer's Disease (e.g. E280A), how might a high frequency develop in a population and why wouldn't natural selection decrease it?

A high frequency of mutation can be produced by having a small population, leading to high levels of inbreeding. When there is little interbreeding with different populations, the genetic diversity will r...

Answered by Caitlin R. • Biology tutor

2458 Views

How can DNA mutations alter the structure of a protein?

Regions of an organism's genome that code for proteins are known as genes. The sequence of deoxyribonucleic acids (bases) in a gene directly translates to the sequence of amino acids in the protein it enc...

Answered by Lewis B. • Biology tutor

2973 Views

Describe 2 ways in which the body prevents entry of microorganisms into the body

-acid in the stomach kills any pathogens-skin acts as a physical barrier to pathogens-hair in the nose and ears trap any pathogens -saliva & mucous trap pathogens. The bronchi have villi that help mov...

Answered by Sara H. • Biology tutor

3799 Views

Describe the pathway of electrical activity in the heart during the cardiac cycle.

The wave of excitation originates in the sinoatrial node in the right atrium. From there, it travels through the right and left atria, causing contraction of the atria (atrial systole). It is prevented fr...

Answered by Josh W. • Biology tutor

2971 Views