L23. Bacterial Growth

Question 1

Name the following 4 stages of bacterial growth :
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Answer 1

Lag phase
Log phase
Stationary phase
Death

Question 2

Which type of agar can grow anything?

Answer 2

Non selective blood agar.

Question 3

What can/can’t mannitol salt agar grow?

Answer 3

It inhibits most bacteria due to its salt content but others (eg staph aureas and staph epidermidis) can still grow.

Question 4

Which type of bacteria has a thick peptidoglycan cell wall so retains the stain (purple)?

Answer 4

Gram positive (+ means with stain)

Question 5

Which bacteria type has a thin peptidoglycan cell wall so doesn’t retain the stain (pink)?

Answer 5

Gram negative bacteria (- means no stain retained)

Question 6

Which substance inside a bacterial cell is very toxic?

Answer 6

Lipopolysaccharides/endotoxins

Question 7

What shape are bacilli?

Answer 7

Rod-shaped

Question 8

What shape are cocci?

Answer 8

Circular balls

Question 9

Which bacteria causes acute ulcerative gingivitis?

Answer 9

Spirochetes (spiral shaped)

Question 10

Give an example of a bacteria and subsequent condition condition caused by :
gram positive cocci

Answer 10

s mutans (caries)

Question 11

Give an example of a bacteria and subsequent condition caused by :
gram positive bacilli

Answer 11

clostridium tetani (tetanus)

Question 12

Give an example of a bacteria and subsequent condition caused by :
gram negative bacilli

Answer 12

E.coli (stomach ache)

Question 13

Give an example of a bacteria and subsequent condition caused by :
gram negative cocci

Answer 13

Neisseria meningitidus (meningitis)

Question 14

What can a faculatative anaerobe do?

Answer 14

Can grow with or without oxygen

Question 15

Give an endogeonous source for angular chelitis

Answer 15

nares

Question 16

What does MRSA stand for?

Answer 16

Methicillin (antibiotic)
resistant
staph
aureas