What is the theory of endosymbiosis? What is the theory of autogeny? What organelles’ origins are explained by each theory, and what evidence is there for the validity of the endosymbiotic theory? 

The theory of endosymbiosis emphasizes that during the history of life, symbiosis has played a role in branching out from a few common ancestors to many descendent species. it is an evolutionary theory of the origin of eukaryotic cells from prokaryotic organisms advanced where the organelles distinguishing eukaryote cells evolved through symbiosis of individual single-celled prokaryotes autogeny was alternative theory of cellular respiration as it is thought to be that all eukaryotic cells evolved through a slow branching evolution. the original ancestor was a photosynthetic bacterium. The evidence for endosymbiotic theory includes the following is that Mitochondria possess a circular genome in which transcription is coupled to translation, characteristic of bacterial DNA.

it divides and replicate independently of host cell division and do so in a manner akin to binary fission, possessing homologues of the bacterial division protein. They are enclosed by a double-membrane and they have same size and shape of bacteria.

7.Compare and contrast the structure and functions of the three types of cytoskeletal fibers. What proteins make up each of the three types of cytoskeletal fibers? What are the differences in size and function among te three fiber  ?