The Prokaryotes (Archaea and Bacteria Domains)

Question 1

What are key features of Prokaryotes?

Answer 1

1. Unicellular
2. Can survive in a broad range of environments
3. No internal organelles
4. Posses distinct ribosomes
5. 20X smaller cells than Eukaryotes
6. Chemically** unique cell walls**
7. Circular chromosome with smaller plasmids
8. **Asexual **and rapid binary fission

Question 2

What does the Prokaryote plasma membrane consist of?

Answer 2

1. Phosphalipid bilayer
2. Hydrocarbon chains have no branches
3. Ester linkage

Question 3

What are unique features of Archaeal Membrane Lipids?

Answer 3

1. Some are a lipid monolayer
2. Have multiple branches and rings
3. Ether linkage is more chemically stable

Question 4

What is the cell wall of bacteria made from?

Answer 4

Peptidoglycan which is amino acids and sugar assembled alternating between NAG and NAM

Question 5

What is the difference between Gram(-) and Gram(+) cell walls?

Answer 5

Gram(-) has a thinner peptidoglycan layer and a** second outer membrane** with lipopolysaccharides and the space between is called the periplasmic space

Question 6

What are key features of Proteobacteria and what are examples?

Answer 6

1. Largest and most diverse
2. 5 major subgroups
3. Some capable of nitrogen fization

Rhizobuim, Salmonella (gamma), helicobacter pylori (epsilon), E.coli (gamma), Vibrio Cholera (gamma)

Question 7

What domain does Cholera belong to?

Answer 7

Proteobacteria

Question 8

What are key features and examples of Chlamydias?

Answer 8

1. Only survive as obligate parasites
2. Small as .3Micrometers
3. Endocytosis into the vacuoles
4. Develop int larger noninfectious reticulate bodies

Chlamydia trachomatis

Question 9

What are key features and examples of Spirochetes?

Answer 9

1. Tightly coiled and slender
2. Motile with 1+ flagella at each end called endoflagella

Borrelia burgdorferi (causes Lyme Disease)

Question 10

What are key features of Cyanobacteria?

Answer 10

1. Called Blue-green Algae
2. Capable of Photosynthesis
3. Some form biofilms

Question 11

What are key features and examples of Endospore Forming Gram Positive Bacterias?

Answer 11

1. Found in soil
2. Enter a dormant stage called the Endospore when they run out of nutrients
3. Difficult to kill

Clostridium botulinum

Question 12

What are key features and examples of Nonsporulating Gram Positive Bacterias?

Answer 12

1. Staphylococci and Streptococci
2. harmless but some are notorious pathogens

Staphylococcus aureus

Question 13

What are key features of Archaea Euryarchaeotes?

Answer 13

1. Phylogenies based on RNA sequences
2. Anerobic
3. Methanogens
4. Species can survive in conditons of extremely high salt and temperature, and low pH

Question 14

What are features and examples of Extreme Thermophiles?

Answer 14

1. Optimum growth at 100 Celcius

Pyrococcus furiosus

Question 15

What are key features and examples of Extreme Acidophiles?

Answer 15

1. Optimum growth at pH<2 but keep a pH of around 6.4

Thermoplasma acidophilum

Question 16

What are key features and examples of Extreme Halophiles?

Answer 16

1. Survive in high salt environments
2. Some will die in salt levels below 9%

Haloarchaea