In a Perfectly Controlled Laboratory Environment,a Pure-Breeding Fish with a 23-Mm

question 14

Essay

In a perfectly controlled laboratory environment,a pure-breeding fish with a 23-mm tail was crossed to a pure-breeding fish with a 15-mm tail.In the F₁,all individuals had tails of an intermediate length: 19 mm.If tail length is a typical polygenic trait controlled entirely by the equal and additive effect of two unlinked genes,each with two alleles ("+" and "-"),what phenotypic ratios do you expect to find in the F₂?

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Definitions:

Superior to Inferior

Describes a direction in anatomy going from the upper part of the body towards the lower part.

Pharynx

A muscular tube that connects the mouth and nasal cavities to the esophagus and larynx, serving both the respiratory and digestive systems.

Esophagus

Portion of the digestive tract between the pharynx and stomach.

Parietal Peritoneum

Layer of peritoneum lining the abdominal walls.