Chloroplasts are proposed to have arisen after archaea cells

Chloroplasts are proposed to have arisen after archaea cells engulfed ___, in endosymbiosis, allowing the engulfed cell to remain, with specialized function

aerobic bacteria

aerobic archaea

photosynthetic bacteria

photosynthetic archaea

anaerobic bacteria

Solution

Ans. Chloroplasts are proposed to have arisen after archaea cells engulfed photosynthetic bacteria, in endosymbiosis, allowing the engulfed cell to remain, with specialized function.   

The chloroplast of plants closely resembles to cyanobacteria (a photosynthetic bacteria). SO, the organelle is supposed to have evolved when a larger cell (archaean) engulfed it and both the cells exhibited symbiosis.

Since chloroplast carriers out photosynthesis, the engulfed cell must also be photoautotroph. So, all options including aerobic bacteria or archaea and anaerobic bacteria are incorrect because they don’t carry out photosynthesis.