Bacteria

Question 1

What are the cellular features of gram positive bacteria?

Answer 1

Thick peptidoglycan wall with teichoic acids and lipoteichoic acids that is relatively porous

Question 2

What is the structure of peptidoglycan?

Answer 2

N-acetyl glucosamine and N-acetyl muramic acid linked horizontally and vertically by peptide chains and pentapeptide bridges

Question 3

What are the features of gram negative cell wall?

Answer 3

An outer membrane, lipopolysaccharides with O-antigen side chains, a peri-plasmic space between the inner and outer layer, thin layer of peptidoglycan - overall a cell wall that is relatively impervious

Question 4

What are the features of acid fast bacteria?

Answer 4

thick waxy walls around a peptidoglycan base, resistant to harsh environments and antibiotics but slow to replicate

Question 5

What are the 5 major groups of bacteria according to their staining characteristics?

Answer 5

gram positive cocci, gram negative cocci, gram positive rods, gram negative rods, acid fast

Question 6

What are the variable characteristics of bacteria?

Answer 6

Flagella, fimbriae, capsules, spores

Question 7

What are the two antigens of E coli used for stereotyping?

Answer 7

O-antigens and H-antigens

Question 8

What are the phases of bacterial growth?

Answer 8

lag phase, log phase, stationary phase

Question 9

What are the three categories of metabolic growth according to final electron acceptor

Answer 9

Respiration (oxygen), anaerobic respiration (non-organic but not oxygen), fermentation (organic)

Question 10

What are the five types of bacteria according to their relationship with oxygen?

Answer 10

Strict aerobes, strict anaerobes, facultative anaerobes, aerotolerant anaerobes (survives but doesn’t grow in oxygen), microaerophiles