An individual mixotroph loses its plastids, yet continues to survive. Which of the following most likely accounts for its continued survival?
A) It relies on photosystems that float freely in its cytosol.
B) It must have gained extra mitochondria when it lost its plastids.
C) It engulfs organic material by phagocytosis or by absorption.
D) It has an endospore.
E) It is protected by a case made of silica.

Question

Quizplus · Accepted Answer

When an individual mixotroph loses its plastids, it is no longer capable of photosynthesis. Therefore, it must either rely on other sources of energy or engulf organic material by phagocytosis or by absorption to survive. Option A is incorrect because photosystems cannot float freely in the cytosol without being enclosed within a membrane-bound organelle like plastids. Option B is incorrect because gaining extra mitochondria does not necessarily provide the energy needed to survive without plastids. Option D is incorrect because an endospore is a specialized dormant structure that protects the bacterial cell during unfavorable environmental conditions and has nothing to do with energy acquisition. Option E is incorrect because while silica is protective, it does not provide a means of energy acquisition.

An Individual Mixotroph Loses Its Plastids, Yet Continues to Survive