Two True-Breeding Mutant Strains of Drosophila Have Black Body Color

question 20

Multiple Choice

Two true-breeding mutant strains of Drosophila have black body color instead of the wild-type gray yellow. When the two strains are crossed, all the F1 flies have wild-type body color. How can these data be interpreted?

• A) Recombination occurred.
• B) The mutations involved are on two different genes.
• C) Complementation occurred.
• D) Both B and C
• E) A new mutation occurred in all the offspring.

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Definitions:

Genitals

The reproductive organs, especially the external sex organs.

Engorged

Swollen with fluid or blood; typically refers to body parts that have filled with such to an extreme level.

Erection

The physiological response resulting in the increased blood flow to the penis, leading to its enlargement and firmness.

Specific Object

A distinct item or entity that is identifiable and can be distinguished from other objects.