Question

this passage describes the leaf type trait in tomato plants:
tomato leaves come in many types, including regular leaves and potato leaves. regular leaves are small and have jagged edges. potato leaves are large and have smooth edges.
in a group of tomato plants, some individuals have regular leaves and others have potato leaves. in this group, the gene for the leaf type trait has two alleles. the allele for potato leaves (l) is recessive to the allele for regular leaves (l).
a certain tomato plant from this group has regular leaves.
based on this tomato plants phenotype for the leaf type trait, which of the following could be its genotype for the leaf type gene? select all that apply.
ll ll ll

Explanation:

Step1: Recall Dominant/Recessive Rules

In genetics, a dominant allele (here, \( L \) for regular leaves) is expressed if present, while a recessive allele (\( l \) for potato leaves) is only expressed in homozygous form (\( ll \)).

Step2: Analyze Genotypes and Phenotypes

• Genotype \( LL \): Homozygous dominant. Since \( L \) is dominant, the plant has regular leaves (matches the phenotype).
• Genotype \( Ll \): Heterozygous. The dominant \( L \) allele is present, so the plant has regular leaves (matches the phenotype).
• Genotype \( ll \): Homozygous recessive. This would express the recessive trait (potato leaves), which does not match the "regular leaves" phenotype.

Answer:

The correct genotypes are \( LL \) and \( Ll \) (so the first two options: \( LL \), \( Ll \)). The \( ll \) genotype is incorrect as it produces potato leaves.