Final answer:
The alternate form of genes offering variability in nucleic acids is known as alleles (Option A). Alleles are found on chromosomes and provide the genetic variations that result in diverse traits among individuals.
Step-by-step explanation:
The correct answer to the question is A) Allele. Alleles are the alternate forms of a gene that are found on chromosomes and provide variability in the genetic makeup of organisms. Within the vast sequence of nucleotides on the DNA, alleles confer the unique combinations that result in different traits.
In biology, understanding how alleles contribute to genetic diversity is fundamental. Each parent donates one allele for each gene, allowing for various combinations in the offspring. These allelic variations are responsible for the multitude of genetic differences observed among people. Although DNA has a limited alphabet of just four nucleotides—adenine (A), thymine (T), cytosine (C), and guanine (G)—these can arrange into countless sequences to form genes. Different alleles arise from variations in these sequences, further contributing to genetic variation.
It is the specific sequence of the nucleotide bases A, T, C, and G in DNA, and A, U, C, and G in RNA, that makes up the genetic code, which in turn dictates the synthesis of proteins. Proteins, being the functional molecules within cells, determine an organism's traits. Therefore, alleles play a critical part in forming the diverse traits and characteristics we see across individuals in a population.