Imagine you want to study human crystallins, proteins present in the lens of the eye. to obtain a sufficient amount of the protein, you decide to clone the crystallin gene. would you construct a genomic library or a cdna library? what material would you use as a source of dna or rna?

Researchers randomly divide participants into groups. each group takes a different amount of omega-3 fatty acid supplements daily for a month. one group receives a placebo. the researchers measure the impact on cholesterol levels in the blood. what is the purpose of random assignment in this experiment? a, to produce treatment groups with similar characteristics b, to ensure that all people with high cholesterol have an equal chance of being selected for the study c, to increase the accuracy of the research results and prevent skewness in the data

All but one describes an effect of aging on the digestive system. a) decreased acid secretion b) decreased elasticity of stomach c) capacity to resist damage decreases d) food remains in stomach for less time

Ialready know the answers to these questions and they are on the attachment. but i just need to know why that answer is the correct one. plz asap! this is for a report that i need to email by 10!