Question

Assume that some members of an aquatic species of motile, photosynthetic protists evolve to become parasitic to fish. They gain the ability to live in the fish gut, absorbing nutrients as the fish digest food. Overtime, which of the following phenotypic changes would you expect to observe in the population of protists?
a.) gain of meiosis
b.) loss of mobility
c.) loss of chloroplasts
d.) no changes would be expected
e.) gain a rigid cell wall

Answer 1

Answer:

c.) loss of chloroplasts

Explanation:

Chloroplasts are the double membrane-bound organelles of photosynthetic eukaryotes and serve as the site for photosynthesis. The organisms that can carry out photosynthesis make the organic nutrients and do not depend on other organisms for food.

According to the given information, the photosynthetic protists become parasite in fish and start deriving nutrition from the host. If the protists continue to survive as a parasite to fish, the chloroplasts will be rendered non-significant. The parasitic mode of nutrition does not require chloroplasts and therefore, the protists would lose the organelles over generations.