Oct 25 Flashcards Preview

EEOB 3310 > Oct 25 > Flashcards

Flashcards in Oct 25 Deck (24):
1

Who proposed the central dogma?

Crick

2

TRUE/FALSE
Compartmentalization increases the concentration of replicated molecules

TRUE

3

The evolution of metabolism was incomplete because of what?

Absence of O2

4

What cellular feature evolved to produce energy while maintaining internal pH?

proton gradient

5

What is a harmful byproduct of metabolism?

H

6

Depletion of organic nutrients in the aqueous environment led to use of what molecule in metabolism?

CO2

7

Membrane-bound NADH dehydrogenase complexes that could exploit energy from sunlight (photochemical reaction centers) likely evolved in ancestors of...

green sulfur bacteria

8

What collect light energy and transfer it to reaction centers?

chlorosomes

9

Cyanobacteria have two photosystems (PSI and PSII) to obtain electron from what molecule?

water

10

Photosynthesis led to what?

increase in oxygen biomass

11

Oxygen levels increased from < 1 billion years?

20%

12

What were the consequences of increased aerobicity?

1) free radicals
2) death of anaerobes
3) large amounts of biomass
4) various metabolic pathways

13

Increased aerobicity led to the emergence of what type of bacteria?

non-photosynthetic

14

The increase in free radicals led to what?

evolution of catalase and superoxide dismutase

15

What is the endosymbiotic theory of eukaryote evolution?

ancient archaea or bacterium engulfed but not consumed-->organelles

16

Which organelles have their own genomes?

mitochondria and plastids

17

Ribosomal RNA is most similar to...

bacteria

18

Mitochondria and plastids are believed to come from...

mitochondria-->ancient gammaproteobacterium
plastid-->ancient cyanobacterium

19

How do aerotolerant anaerobes deal w/ free radicals?

encode catalase and superoxide dismutase

20

What are 2 theories about the origin of the nucleus?

1) from archaea post-acquisition of organelles
2) horizontal transfer of genes between nucleus and mitochondria and/or plastids

21

TRUE/FALSE
Many insects harbor bacterial symbionts intracellularly

TRUE

22

Bacterial symbionts have (large/small) genomes

small

23

What is a phenomenon of bacterial symbionts?

speciate w/ hosts

24

How do bacterial symbionts benefit their host?

Provide their hosts with nutrients missing from their diets