A Couple Are Both Heterozygous for the Dominant Allele for Polydactyly

question 29

Multiple Choice

A couple are both heterozygous for the dominant allele for polydactyly. They want to have three children. What is the probability that all three children will have polydactyly?

• A) 3/4
• B) 9/64
• C) 1/64
• D) 27/64
• E) 1/2

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Definitions:

Alginic Acid

A polysaccharide distributed widely in the cell walls of brown algae, used as a food thickener and pharmaceutical ingredient.

Brown Algae

A large group of mostly marine, multicellular algae, including many seaweeds commonly found in colder waters.

Emulsifying Agent

A substance that helps to mix two immiscible liquids, such as oil and water, to form a stable mixture called an emulsion.

Pellicle

An outer layer of plasma membrane and elastic proteins that protects and gives shape to many unwalled, single-celled protists.