A Black Guinea Pig Crossed with a Guinea Pig with Albinism

question 35

Multiple Choice

A black guinea pig crossed with a guinea pig with albinism produced 12 black offspring. When the albino was crossed with a second black animal, six blacks and six albinos were obtained. What is the best explanation for this genetic situation?

• A) Albinism is a recessive trait; black is a dominant trait.
• B) Albinism is a dominant trait; black is incompletely dominant.
• C) Albinism and black are codominant.
• D) Albinism is a recessive trait; black is codominant.

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Definitions:

Major Depressive Disorder

A psychiatric condition characterized by a persistent feeling of sadness or a lack of interest in external stimuli.

Optimistic

Having a positive outlook on future events, believing in the best possible outcome.

Diagnostic Reliability

The consistency and stability of a diagnosis over time or between different assessors.

DSM-IV-TR

The Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision; a handbook used by healthcare professionals in the United States as an authoritative guide to diagnose mental disorders.