Microbiology

Question 1

Structure of Gram negative bacteria

Answer 1

Thin cell wall of peptidoglycan (DO NOT RETAIN CRYSTAL VIOLET)

Outer membrane consisting of Lipopolysaccharides
(Lipopolysaccharides provide some resistance to antibiotics and the enzyme lysozyme)

Question 2

Lysozyme Function

Answer 2

Breaks down cell walls of bacterium

Peptidoglycan in the cell walls is the specific active site that lysozyme targets

Question 3

What colour does Gram negative bacteria stain by counter stain

Answer 3

Red

Question 4

Ways of safely disposing bacterial culture plates

Answer 4

Put into biohazard bags

Use of autoclave at 121 degrees for 15-30 minutes (100kPa/ 15psi)

Question 5

Obligate anaerobes

Answer 5

Require oxygen for growth at all times

Question 6

Obligate anaerobes

Answer 6

Cannot grow in the presence of oxygen as it inhibits their growth

Question 7

Facultative anaerobes

Answer 7

Grow best in the presence of oxygen but can survive and grow without it

Question 8

What colour do Gram positive bacteria appear with Gram stain

Answer 8

Purple

Question 9

Shape of Coccus bacteria

Answer 9

Round

Question 10

Shape of Bacillus bacteria

Answer 10

Rod-shaped

Question 11

Shape of Spirillum bacteria

Answer 11

Spiral/ Helical