Question

question 26 of 26

which statement is an example of the \blending of traits\ misconception that was popular before mendels work?

a. a black-coated horse and a white-coated horse will have only gray offspring.
b. a short-eared dog and a long-eared dog will have only short-eared offspring.
c. a goat that has lost its leg will have only three-legged offspring.
d. a turtle that stretches its neck will have both long-necked and short-necked offspring.

Explanation:

Define blending inheritance

The "blending of traits" (or blending inheritance) was a widespread belief before Mendelian Genetics became accepted. It proposed that offspring inherit a literal mixture of their parents' physical traits, resulting in an intermediate phenotype, much like mixing black and white paint to get gray.

Analyze the given options

• Option A: A black-coated horse and a white-coated horse having only gray offspring represents an intermediate phenotype (gray) resulting from the mixture of the parental traits (black and white). This perfectly illustrates the blending hypothesis.
• Option B: A short-eared dog and a long-eared dog having only short-eared offspring describes a pattern where one parental trait completely masks the other, which is an example of complete dominance rather than blending.
• Option C: A goat losing its leg and having three-legged offspring describes the inheritance of an acquired physical characteristic (Lamarckian inheritance), not blending.
• Option D: A turtle stretching its neck and having both long-necked and short-necked offspring also relates to Lamarckian ideas of use and disuse, rather than blending.

Select the correct option

Option A is the only statement that describes parental traits mixing to produce an intermediate, blended trait in the offspring.

Answer:

• (A) A black-coated horse and a white-coated horse will have only gray offspring. (Correct answer)
• (B) A short-eared dog and a long-eared dog will have only short-eared offspring.
• (C) A goat that has lost its leg will have only three-legged offspring.
• (D) A turtle that stretches its neck will have both long-necked and short-necked offspring.