The statement that best describes the difference between a gene and an allele is that a section of DNA that usually contains the code for a specific protein that determines a specific trait is a gene, while an allele is a section of a gene. The correct option among all the options that are given in the question is the last option or option "D".
<span>Amino acids are the basic structural unit of all proteins. A 'free' amino acid (a single amino acid) always has:
an amino group -NH2,
a carboxyl group -COOH
a hydrogen -H
a chemical group or side chain -"R".
Since the amino acids (except glycine) have 4 different groups attached to the a-carbon, they are optically active stereoisomers (recall 23.101 Organic Chemistry) although only L-isomers are found in proteins.
At a neutral pH, both the amino and the carboxyl groups are ionised, giving what is termed the zwitterionic</span>
starch into glucose
proteins into amino acids
lipids into fatty acids
There are many more examples of chemical digestion which takes place in the body. Chemical digestion is the breaking of larger more complex molecules into smaller, simpler ones that can be taken up by the cells more easily and readily by the use of chemical agents.. Chemical digestion is carried out primarily using biological molecules called enzymes. For example, the breakdown of starch is done by an enzyme known as amylase, which is present in the saliva.
