Lecture 1

Question 1

Name 4 features of Gram-positive bacteria

Answer 1

1. thick layer of peptidoglycan (50%)
2. relatively featureless (no lipids, few proteins)
3. no outer membrane
4. susceptible to cell wall disruption

Question 2

Name 4 features of Gram-negative bacteria

Answer 2

1. pair of membranes (cytoplasmic and outer)
2. thin layer of peptidoglycan
3. high lipid content due to outer membrane
4. resistant to cell wall disruption

Question 2

List 4 functions of cell wall

Answer 2

1. Maintains cell shape, strength & rigidity
2. Protects against osmotic lysis
3. Allows for attachment to cells and other surfaces
4. Provides protection from the immune system

Question 2

Gram postive stain is

Answer 2

purple

Question 2

Gram negative stain is

Answer 2

pink

Question 2

TRUE/FASLE
Some gram-positive bacteria can be
easily decolorized

Answer 2

TRUE

Question 2

TRUE/FALSE
Some gram-negative bacteria can retain
the crystal violet color and appear
somewhat gram-positive

Answer 2

TRUE