Bacterial Anatomy

Question 1

Advantages of being small

Answer 1

• High SA/V ratio = diffusion + absorption is favourable
• Rapid growth
• High cell density
• Increased efficiency

Question 2

Porins; molecule selectivity, direction of molecule passage

Answer 2

• Semi selective; small polar molecules

- BI-directional

Question 3

Beta-lactams function + example

Answer 3

• Acts on cell wall by INHIBITING the growth.

- Penicillin (only inhibits growth of gram +)

Question 4

Why are beta-lactams + lysozymes ineffective on gram negative bacteria?

Answer 4

• 2nd membrane contains porins which make large proteins, polysaccharides and H+ from coming in.

Question 5

Lysozyme

Answer 5

CLEAVES beta 1-4 linkages between sugars (N-Am + N-Ag)

Question 6

Functions of glycocalyx or EPS

Answer 6

• Dehydration protection
• Phagocytosis protection
• Adhesion
• Resistance to outer environment
• Virulence factor

Question 7

Capsule

Answer 7

Highly organized EPS + firmly attached to cell wall

Question 8

Mucoid layer

Answer 8

Poorly organized EPS + loosely attached to cell wall

- Biofilms