In Genetics, the Dash Symbol (-) Is a "Wild Card

question 129

Multiple Choice

In genetics, the dash symbol (-) is a "wild card" that stands for either the dominant allele or the recessive allele; for example, A- means the individual has either the genotype AA or Aa. Two genes that undergo independent assortment affect coat color in Duroc pigs. Each gene has two alleles, one of which is dominant for coat color. Genotypes of the form A- B- are red, those of the form A- bb and aa B- are sandy, and genotype aa bb is white. What ratio of red : sandy : white is expected from the cross Aa Bb × Aa Bb?

• A)10:3:3
• B)9:3:4
• C)12:3:1
• D)9:6:1

---

Definitions:

Guthrie

Refers to Edwin Ray Guthrie, a psychologist known for his theory that learning is based on a stimulus-response association.

Learning Theory

A set of theories that describe how behaviors are acquired, processed, and retained through interaction with the environment.

Single Trial

A learning or experimental situation where an organism is exposed to a stimulus or condition only once, used to assess immediate and initial responses.

Reward

A stimulus or event that increases the likelihood of a behavior being repeated, often pleasant or beneficial in nature.