Microbiology

Question 1

What are the four major groups of human pathogens?

Answer 1

Protozoa, fungi, bacteria and viruses

Question 2

What are Protozoa?

Answer 2

Single called animals, they are eukaryotes

Question 3

What are fungi?

Answer 3

Higher plant like organisms, they are eukaryotes

Question 4

What are viruses?

Answer 4

Generally small, single celled prokaryotes

Question 5

How can energy be made in the absence of a mitochondria?

Answer 5

The cell membrane can produce energy via the electron transport chain

Question 6

What does the nucleoid contain?

Answer 6

DNA and proteins

Question 7

General structure of the cell wall?

Answer 7

Repeated polysaccharide structure

Question 8

Structure of gram positive bacteria

Answer 8

They have cell walls composed of thick layers of peptidoglycan

Question 9

What colour do gram positive cells stain when subjected to a gram stain procedure?

Answer 9

Purple

Question 10

What are the targets for penicillin?

Answer 10

Peptidoglycan cross links

Question 11

Structure of gram negative bacteria

Answer 11

They have cell walls with a thin layer of peptidoglycan

Question 12

Difference with a gram -ve compared to a positive

Answer 12

It has an outer membrane, a periplasm and a thinner PG layer

Question 13

What is the very outer membrane of gram negative bacteria?

Answer 13

Lipopolysaccharide

Question 14

What do fimbrae allow?

Answer 14

Increased surface area contact and specificity to different tissue. It can mediate the transfer of material (bacterial sex)

Question 15

What can bacterial secretion systems secrete?

Answer 15

DNA, RNA and protein into cells

Question 16

What does a prokaryote need to grow?

Answer 16

Carbon (from proteins/sugars/CO2)
Oxygen, hydrogen and nitrogen = from amino acids, ammonia
Vitamins
Body temperature
Human Ion Conc (pH 6.8-7.2)
Osmotic protection

Question 17

What can bacteria do if there is not enough oxygen?

Answer 17

Switch to anaerobic growth but this can lead to tissue damage and other negative implications

Question 18

How do most bacteria exist?

Answer 18

As communities and not in isolation