Which term refers to the alternative forms of a gene?

Which term refers to the alternative forms of a gene?

• A. Heredity
• B. Genetic screening
• C. Alleles
• D. Codon/Triplet

Answer: (C)

The idea being tested is that a gene can exist in different forms, called alleles. A gene is a specific sequence on a chromosome that influences a trait, and alleles are the alternative versions of that same gene at the same location. These different forms arise through mutations and create variation in what traits are seen in individuals. In most organisms you inherit two alleles for each gene, one from each parent, and the combination you have helps determine your phenotype depending on how the alleles interact. For example, the ABO blood group system depends on different alleles at one gene, giving rise to different blood types. The other terms describe something else: heredity is the passing of traits through generations, genetic screening is testing DNA for conditions, and a codon/triplet is a three-nucleotide sequence in RNA that codes for an amino acid, not a version of a gene.

The idea being tested is that a gene can exist in different forms, called alleles. A gene is a specific sequence on a chromosome that influences a trait, and alleles are the alternative versions of that same gene at the same location. These different forms arise through mutations and create variation in what traits are seen in individuals. In most organisms you inherit two alleles for each gene, one from each parent, and the combination you have helps determine your phenotype depending on how the alleles interact. For example, the ABO blood group system depends on different alleles at one gene, giving rise to different blood types. The other terms describe something else: heredity is the passing of traits through generations, genetic screening is testing DNA for conditions, and a codon/triplet is a three-nucleotide sequence in RNA that codes for an amino acid, not a version of a gene.