Archaea & Bacteria

How are bacteria classified?

1. metabolism (mode of nutrition)

2. ability to produce endospores

3. motility

4. shape

5. peptidoglycan cell wall

What are resistant bodies that bacteria release when their environment becomes difficult to live in?

endospores

What do endospores contain?

1. DNA

2. small amount of cytoplasm

What are the bacterial means of motility?

1. flagella

2. corkscrew motion

3. gliding through slime material

Which bacterial shape is spherical?

cocci

Which bacterial shape is rod-shaped?

bacilli

Which bacterial shape is spiral?

spirilla/spirochete

Which bacteria have thick peptidoglycan cell walls?

gram-positive

Which bacteria have thin peptidoglycan covered with lipopolysaccharides?

gram-negative

What special sugars does peptidoglycan contain?

amino sugars

What molecules are used as recognition and binding sites by bacterial viruses that cause infections?

teichoic acids

Where are teichoic acids found?

cell wall

On which bacteria are teichoic acids only found?

gram positive

How are the teichoic acids attached to the peptidoglycan layer?

covalent bonds

Which bacteria are photosynthetic and contain an accessory pigment called phycobilins?

cyanobacteria

What specialized cells do cyanobacteria contain that produce nitrogen-fixing enzymes?

heterocysts

The nitrogen-fixing enzymes produced by heterocysts convert fixed inorganic nitrogen gas into NH3 that can be used to make what?

amino acids and nucleotides

What is the common name for cyanobacteria?

blue-green algae

(Note: not related to

eukaryotic algae groups)

Of what organisms are the oldest known fossils?

cyanobacteria

Where can cyanobacteria grow?

they grow rapidly in aquatic environments, turing water green or blue-green

Which bacterial group contains nitrifying bacteria, which are able to convert ammonia to nitrate with autotrophic metabolism?

chemosynthetic

Which bacteria are heterotrophs that fix N2?

nitrogen-fixing

Where do nitrogen-fixing bacteria live?

nodules of plants

(Note: a form of mutualism)

Which bacterial group contains coiled bacteria that move with a corkscrew motion via internal flagella between cell wall layers?

Spirochetes

Which type of cells are archaeans?

prokaryotic

Archaean cell walls are composed of what structural component?

polysaccharides

The phospholipids in archaean cells contain which type of linkage?

ether

What shape is the hydrocarbon chain in archaea?

branched

DNA of which domains is associated with histones?

1. archaea

2. eukarya

Which organelle's activity is not inhibited by antibiotics streptomycin and chloramphenicol in archaeans?

ribosome activity

Which group of archaea contains obligate anaerobes that

produce CH4?

methanogens

(Note: produced as

a by-product of

obtaining energy

from H2 to fix CO2)

Which group of archea lives in extreme environments?

extremophiles

Which extremophiles live in high salt concentration environments?

halophiles

(Note: salt lovers)

What metabolism do halophiles possess?

aerobic

To which category of energy utilization do most halophiles belong?

heterotrophic

(Note: others are anaerobic and photosynthetic with the pigment bacteriorhodopsin)

Which extremophiles are sulfur-based chemoautotrophs that live in very hot places?

thermophiles

(Note: heat lovers)