Question

which structure will form when a primitive cell engulfs an aerobic bacterium?
○ mitochondria
○ chloroplast
○ nucleus
○ cell membrane

Explanation:

According to the endosymbiotic theory, when a primitive cell engulfs an aerobic bacterium, the bacterium evolves into a mitochondrion. Chloroplasts are formed from engulfing photosynthetic bacteria, the nucleus is not formed via engulfing bacteria, and the cell membrane is a pre - existing structure of the cell, not formed by engulfing a bacterium.

Answer:

A. mitochondria