Question

question 1 10 pts what is the endosymbiotic theory primarily about? the origin of mitochondria and chloroplasts from ancient bacteria the evolution of single - celled organisms into multicellular ones the formation of the nuclear membrane the development of cell walls in plant cells question 2 10 pts how long ago did the events described in the endosymbiotic theory take place? over 2 billion years ago 1 billion years ago 3 billion years ago 500 million years ago

Explanation:

Question 1

The endosymbiotic theory explains that mitochondria and chloroplasts in eukaryotic cells originated from ancient prokaryotic bacteria (like proteobacteria for mitochondria and cyanobacteria for chloroplasts) that were engulfed by larger cells and developed a symbiotic relationship. The other options: evolution of single - cell to multi - cell is about multicellularity evolution, nuclear membrane formation is related to other cellular evolution aspects, and cell wall development in plants is not the focus of endosymbiotic theory.

The events of endosymbiotic theory (the engulfment and symbiotic development of the bacteria that became mitochondria and chloroplasts) are estimated to have occurred over 2 billion years ago. This is a well - established timeline in the study of cellular evolution.

Answer:

A. The origin of mitochondria and chloroplasts from ancient bacteria

Question 2