Consider the Following Genetic Study Involving Two Autosomal Genes

question 21

Multiple Choice

Consider the following genetic study involving two autosomal genes. One of these, eye colour, has the dominant allele (R) for red eye colour and the recessive allele (r) for yellow eye colour. The other has the dominant allele (T) leading to paws with thumbs, while the recessive allele (t) codes for paws without thumbs. If these genes are not linked, what should be the phenotype ratio of the offspring produced by a testcross (RrTt × rrtt) ?

• A) 1 red-eyed with thumbs : 1 yellow-eyed without thumbs
• B) 1 red-eyed with thumbs : 1 yellow-eyed with thumbs : 1 red-eyed without thumbs : 1 yellow-eyed without thumbs
• C) 3 red-eyed with thumbs : 1 yellow-eyed without thumbs
• D) 9 red-eyed with thumbs : 3 yellow-eyed with thumbs : 3 red-eyed without thumbs : 1 yellow-eyed without thumbs

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Definitions:

Ethnic Group

A community or population of individuals who share common cultural, linguistic, or ancestral heritage.

Bayley Scales

A standard series of measurements developed by psychologist Nancy Bayley used to assess the developmental progress of infants and toddlers.

Adaptive

Characterizes something that is able to adjust effectively to new conditions or environments, showing flexibility and resilience.

Developmentally Appropriate

Developmentally appropriate refers to practices or interventions that are suited to the age, individual characteristics, and developmental stage of a person, often used in the context of education or child care.