According to the endosymbiotic theory, why was it adaptive for the larger host) cell to keep the engulfed cell alive, rather than digesting it as food?
A) The engulfed cell provided the host cell with carbon dioxide.
B) The engulfed cell allowed the host cell to metabolize glucose.
C) The host cell was able to survive anaerobic conditions with the engulfed cell alive.
D) The engulfed cell provided the host cell with ATP.
E) The host cell would have been poisoned if it had digested the engulfed cell.

Question

Quizplus · Accepted Answer

The engulfed cell, which eventually became the mitochondria, provided the host cell with the ability to produce ATP through aerobic respiration. This gave the host cell an energy advantage, making it adaptive to keep the engulfed cell alive.

According to the Endosymbiotic Theory, Why Was It Adaptive for the Larger