What is the difference between a gene and an allele?

• A. A gene is a segment of DNA that codes for a trait, while an allele is a variant form of a gene.
• B. A gene is a variant form of a trait, while an allele is a segment of DNA that codes for a trait.
• C. A gene is a type of protein, while an allele is a type of RNA.
• D. A gene is a physical location on a chromosome, while an allele is a type of chromosome.

Answer: (A)

Verified step by step guidance

1. Begin by understanding the basic definitions: A gene is a segment of DNA that contains the instructions for building a specific protein or set of proteins, which in turn determine a particular trait.
2. Next, clarify what an allele is: An allele is a variant form of a gene. Different alleles can lead to variations in the expression of a trait.
3. Consider the relationship between genes and alleles: While a gene is the overall unit that codes for a trait, alleles are the different versions of that gene that can exist. For example, the gene for eye color may have alleles for blue, brown, or green eyes.
4. Reflect on the genetic makeup: In diploid organisms, individuals have two alleles for each gene, one inherited from each parent. These alleles can be the same (homozygous) or different (heterozygous).
5. Finally, distinguish between the options given: The correct distinction is that a gene is a segment of DNA that codes for a trait, while an allele is a variant form of a gene. This understanding helps differentiate the roles of genes and alleles in genetics.