Extranuclear inheritance was first described by Carl Correns based on his observations of Mirabilis jalapa (the four o'clock plant).M.jalapa can have either white,variegated (white and green)or green leaves.Pollen from a variegated M.jalapa plant is used to fertilize a white M.jalapa flower.Which of the following phenotypes would you expect to see in the offspring of this cross?
A)White
B)Green
C)Variegated
D)White and variegated
E)White,green,and variegated

Question

Quizplus · Accepted Answer

CExtranuclear inheritance, often involving chloroplasts which are responsible for the green color in plants, can result in variegation. Since the pollen (male) does not contribute chloroplasts to the offspring in most plants, the offspring's phenotype depends on the mother's phenotype. In this case, the mother plant is white, lacking functional chloroplasts, so the offspring can only be white or potentially variegated if the variegation is due to a mutation in the chloroplast DNA that can be passed from the mother. However, since the mother plant is white, the primary expectation is white offspring, but variegation can occur due to mutations or segregation of chloroplasts during cell division. Green offspring are not expected because the white mother plant does not have green chloroplasts to pass on.

Extranuclear Inheritance Was First Described by Carl Correns Based on His