Flashcards in Lecture 23 - Endosymbiotic Theory and Protist Diversity Deck (21):
Darwin thought that evolution was driven by _______
What did natural selection favor?
-organisms that were best able to out-compete others
-left more descedants
What is another strategy driven by natural selection?
What is an example of a mutualistic symbiosis?
What is symbiosis?
-2 species live in close contact: larger host, smaller symbiont
Who do microbes often form symbiotic relationships with?
What is mutualism?
both symbiotic organisms benefit
one organism benefits white neither helping/harming the other in any sig. way
harms but does not kill its host
What are pathogens
parasites that cause disease
What was the theory of serial endosymbiosis?
-mitochondria and chloroplasts were formally small prokaryotes living within larger cells
What are endosymbionts
cells that live within other cells
What were the proposed ancestors of mitochondria?
-aerobic heterotrophic prokaryotes
proposed ancestors of chloroplasts?
What may have been an ancestral host cell
archaean or protoeukaryote
What were 3 things that endosymbiosis probably lead to?
3. eukaryotic features
What are 5 similarities between bacteria and chloroplasts/mitochondria of eukaryotes?
1. similar size
2. enzymes + transport systems
4. transfer RNAs, ribosomes
What is kleptoplastidy?
stealing and using chloroplasts from prey
What did the plastid-bearing lineage of protists evolve into?
(red + green algae)
Where did mitochondria first arise?
-through descent from a bacterium that was engulfed by a cell from an archaeal lineage