Answer:The hypothesis that eukaryotic cells evolved from a symbiotic association of prokaryotes—endosymbiosis—is particularly well supported by studies of mitochondria and chloroplasts, which are thought to have evolved from bacteria living in large cells.
Explanation:
Answer:
Those organisms are fit which has the ability to survive in harsh climatic condition and transfer their traits to the next generation through the process of reproduction.
Explanation: Fit means they are strong and compete with other organisms for food, shelter and other survival items. Those organisms which are not fit could not survive in harsh environmental conditions and removed from that ecosystem.
