Question

an individual of a plant species shows a certain physical characteristic that requires two copies of the same allele to be expressed. based on this information, how would the allele for the characteristic most likely be classified?
a recessive
b dominant
c sex - linked
d polygenic

Explanation:

To determine the allele type, we analyze each option:

• Recessive alleles require two copies (homozygous recessive, e.g., \( aa \)) to be expressed, as dominant alleles (\( A \)) would mask them if present.
• Dominant alleles are expressed with one or two copies (\( AA \) or \( Aa \))—no need for two identical alleles.
• Sex - linked traits relate to sex chromosomes (X/Y) and don’t depend on two identical alleles for expression.
• Polygenic traits involve multiple genes, not a single allele requiring two copies.

Since the plant needs two copies of the same allele, the allele is recessive.

Answer:

A. Recessive