Question

A scientist is studying fruit fly wings. Straight wings are dominant, and curly wings are recessive. Which statement correctly describes the F1 generation if a straight-winged parent is crossed with a curly-winged parent and if both parents are true breeding?
The offspring will have two genes for straight wings.
The offspring will produce only gametes that have genes for curly wings.
The offspring will have one allele for straight wings and one allele for curly wings.
The offspring will have only one kind of allele for the gene that determines wing type.

Answer 1

"The offspring will have one allele for straight wings and one allele for curly wings."

Explanation: A true-breeding straight parent is homozygous dominant (SS) and a true-breeding curly parent is homozygous recessive (ss). All F1 offspring are heterozygous (Ss) — they display the dominant straight-wing phenotype but carry one recessive allele.