Lecture 15-17 Review

Question 1

Give the 5 phyla of Archaea:

Answer 1

1. Euryarchaeota
2. Thaumarchaeota
3. Nanoacrhaeota
4. Korarchaeota
5. Crenarcheaeota

Question 2

Give 6 common traits in all Archaea

Answer 2

1. evolution of archaea is driven by horizontal gene transfer b/w phyla
2. ether linked lipids
3. lack of peptidoglycan in cell walls
4. structurally complex RNA polymerases
5. RNA polymerases resemble eukaryotic enzymes
6. chemoorganotrophic or chemolithotrophic organisms

Question 3

Describe euryarchaeota characteristics

Answer 3

• halophillic (salt-loving)
• some are obligate aerobes
• some are methanogens (the strictest of anaerobes)
• hyperthemophillic
• acidophillic

Question 4

Give and describe 2 organisms that represent halophilic euryarchaeota

Answer 4

1. halococcus: largest plasmids in nature, 30% of total cellular DNA
2. Haloquadratum: have gas vesicles for floating in hypersaline environment

Question 5

Certain euryarchaeota do not synthesize or accumulate organic compounds. Instead, what do they do?

Answer 5

They pump large amounts of K+ from the enviro into the cytoplasm
= more K+ inside the cell than outside –> this maintains (+) water balance

Question 6

Give 2 hyperthermophilic euryarchaeota

Answer 6

1. thermococcus
2. thermoplasma

Question 7

Thermoplasma is a hyperthermophilic organism that has a ___(small/large) genome.
Its DNA is in globular ___-like structures, and it has a ______ cell wall built like lipid monolayer with mannose & glucose

Answer 7

small

eukaryotic

lipoglycan

Question 8

Methanogens=

Answer 8

microorganisms that produce methane (CH4) as an integral part of their energy metabolism
- they’re the strictest of anaerobes

Question 9

The major source of biogenic methane in nature are _____

Answer 9

methanogens

Question 10

Give 2 acidiophilic euryarchaeota organisms

Answer 10

Ferroplasma
- cell-wall lacking, strong acidophile, uses Fe2+ as e- donor

Picrophilus
- more acidophilic than ferroplasma; grows optimally at pH 0.7

Question 11

which organelles are derived from bacteria?

Answer 11

mitochondria
chloroplasts
hydrogenosomes

Question 12

primary endosymbiosis gave rise to the ______ in the common ancestor of green algae, red algae, & plants

Answer 12

chloroplast