Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Microbiology > Archaea > Flashcards

Archaea Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

What are archaea?

A

Prokaryotic and unicellular organisms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Where are archaea found?

A

Thrive in earthos ecological niches. Extreme environments.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What was rRNA used for?

A

Subunit of ribosome which was used as a molecular chonometer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Why was ssrRNA a ood molecular chronometer?

A

Universal. Conserved. Abundant.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What does the phlya Crenarchaeota include?

A

thermophiles (extreme), psychrophiles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What does the phlya Euryarchaeota include?

A

halophiles, methanogens, thermophiles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What does the phlya Nanoarchaeota include?

A

has one single organism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What does the phlya

Korarchaeota include?

A

know they exist due to rRNA but haven’t been able to culture them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What does the phlya Thaumarchaeota include?

A

originally in open ocean, non extreme, adapted where nitrogen in short supply, soil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is an extremophile?

A

Organism that thrives in an extreme environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are obligate extremophiles?

A

Must have conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are facultative extremophiles?

A

Can tolerate conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Where do thermophilic archaea live?

A

Fumaroles, hot springs, deep sea vents

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What issues do thermophilic archaea face?

A

Denaturation of molecules (proteins). Membrane fluidity (more fluid). Solubility of gases in liquids.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How do thermophilic archaea survive?

A
  • Monolayer membranes
  • Link using an ether link (stronger)
  • Thermostable proteins
  • Chaperonins
  • Mecahnisms to protect DNA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is a monolayer membrane?

A

Single phospholipd layer - uses biphytanyl and crenarchaeol

17
Q

What are thermostable proteins?

A

highly hydrophobic core - increases internal ‘sticking’ - more salt bridges (ionic interactions) so proteins remain folded

18
Q

What are chaperonins?

A

Specialist proteins. Function is to refold partially denatured proteins.

19
Q

What mechanisms are there to protect DNA from heat?

A
  • Increased cellular solute levels prevents chemical damage to DNA
  • Reverse DNA gyrase - positive supercoils - prevents unwinding
  • DNA binding proteins in Euryarchaeota - highly basic proteins that wind and compact DNA into nucleosome like structures
20
Q

Where do you find halophilic archaea?

A

Salt lakes. Dead seas. Hypersaline habitats.

21
Q

What issues do halophilic archaea face?

A

Osmotic forces - need to maintain water balance and compatible solutes

22
Q

How might halophilic archaea solve their issues?

A
  • Pumping inorganic ions into the cell from the environment

- Synthesis organic solutes

23
Q

What are Comptabile Solutes?

A

Compounds that adjust the water balance

24
Q

What are the most studied halophilic archaea?

A

Halobacterium

25
Q

How do halobacterium survive in the dead sea?

A
  • Pumps K+ inside the cell so that the concentration of K+ in the cell is greater than outside
    -Water therefore flows into the cell
    -Glycoprotein cell wall
    -Stabilised by Na+
  • Cytoplasmic proteins are also acidic
    Lower levels of hydrophobic amino acids
26
Q

What would happen to the halobacterium if there was a loss of Na+?

A

Loss of cell wall integrity

27
Q

Where would you find Psychrophilic Archaea?

A

Antarctica. Icy seas. Alpine and polar environments. Temps 1 to -10. Metabolize at -40. Sruvive at -45

28
Q

What problems do Psychrophilic Archaea face?

A

Decreased membrane fluidity

Issue of solute chemistry

29
Q

How do Psychrophilic Archaea survive?

A
  • Cell membranes, unsaturated lipids, double bonds (won’t pack)
  • more proteins containing noncharged amino acids
  • lower content of hydrophobic amino acids
  • Antifreeze proteins
30
Q

Where would you find Methanogenic Archaea?

A

Where there is no oxygen - swamps, ocean, lake sediments and animal digestive tracts

31
Q

What are the different pathways of the Methanogenic Archaea?

A
  1. CO2 reduction pathway
  2. Methylotrophic pathway
  3. Acetoclastic pathway
32
Q

Describe the CO2 reduction pathway?

A

CO2
Form HCOO-
CO - carbon monoxide

33
Q

What are the substrates of the Methylotrophic pathway?

A

Methanol
Methylamine
Dimethylamine

34
Q

What are the substrates of the Acetoclastic pathway?

A

Acetate

Pyruvate

35
Q

What can cell walls of archaea be composed of?

A

Pseudomurein. Polysaccharide. Glycoprotein.

36
Q

What biotechnology are archaea used in?

A
  • PCR and thermostable DNA - wouldn’t be able to do this without archaea
  • Biodegradation of toxic compounds
  • Biomining - use and produce unusual compound
  • Thermostable enzymes
37
Q

What does archaea raise the possibility of?

A

Life on other planets

38
Q

How is the cell envelope of Archaea different from bacteria?

A

Monolayer - biphytanylu. Surrounded by a layer of protein or pseudomurein.

Microbiology (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions