In Drosophila Melanogaster,vestigial Wings Are Caused by a Recessive Allele

question 26

Multiple Choice

In Drosophila melanogaster,vestigial wings are caused by a recessive allele of a gene that is linked to a gene with a recessive allele that causes black body color.Morgan crossed black-bodied normal-winged females and gray-bodied vestigial-winged males.The F₁ were all gray bodied,normal winged.After examining the F₂ progeny,Morgan calculated the map distance to be 17 map units.Which of the following is correct about the F₂ progeny?

• A)black-bodied normal-winged flies = 17%
• B)black-bodied,normal-winged flies PLUS gray-bodied,vestigial-winged flies = 17%
• C)gray-bodied,normal-winged flies PLUS black-bodied,vestigial-winged flies = 17%
• D)black-bodied,vestigial-winged flies = 17%

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Definitions:

Neural

Pertaining to the nerves or the nervous system.

Autocrine

Relating to or denoting a mode of hormone action where a hormone affects the same cell type that produced it.

Nuclear Receptor

A class of proteins within cells that, upon binding with a ligand, can act as transcription factors to regulate gene expression.

G Protein

A type of protein that acts as a molecular switch inside cells, involved in transmitting signals from stimuli outside the cell to its interior.