Microbiology

Question 1

What are viruses and how do they replicate?

Answer 1

Small infectious agents
Can only replicate inside other living cells

Question 2

What are prions and how are they replicated?

Answer 2

Infectious abnormally folded protein
Replicated by inducing normal proteins to form an amyloid plaque
Replicates itself without the need for genetic information

Question 3

Describe protozoas

Answer 3

Single-celled
Heterotrophic
Eukaryotic

Question 4

Describe helminths and how are they separated?

Answer 4

Multicellular
Worm like parasites
Separated into shapes:
Flukes
Tapeworms
Roundworms

Question 5

Describe bacteria

Answer 5

Microscopic
Single-celled
Prokaryotic

Question 6

Describe the cell walls and colour of gram positive and gram negative

Answer 6

Gram positive has thick cell wall and becomes dark purple
Gram negative has inner and outer membrane and becomes light pink

Question 7

Describe endotoxins

Answer 7

Lipopolysaccharide complex associated with the outer membrane of gram -ve

Question 8

Describe exotoxins

Answer 8

Usually secreted by bacteria and act at a site removed from bacterial growth

Question 9

What are the 5 shapes of bacteria?

Answer 9

Cocci = round
Coccobacilli = oval thing
Bacillus = rod
Vibrio = sausage shape
Spirochete = spirally thing

Question 10

Cytosol

Answer 10

Contents of cell within plasma membrane excluding nucleus and organelles

Question 11

Nucleus

Answer 11

Contains DNA, site of transcription

Question 12

Cytoplasm

Answer 12

Contents of cell within plasma membrane excluding nucleus

Question 13

RER

Answer 13

Has ribosomes bound to cytosolic surface, involved in protein synthesis

Question 14

SER

Answer 14

No ribosomes bound, involved in lipid synthesis

Question 15

Golgi Apparatus

Answer 15

Sorting and modification of proteins

Question 16

Mitochondria

Answer 16

Site of ATP production

Question 17

Peroxisome

Answer 17

Oxidation of organic molecules resulting in their breakdown

Question 18

What is the role of endosome?

Answer 18

Processes and sorts molecules that have been internalised into the cell

Question 19

What do lysosomes contain and what is their role?

Answer 19

Contains digestive enzymes that break down macromolecules

Question 20

Plasma Membrane

Answer 20

Selectively permeable layer that surrounds the cell
Phospholipid and protein
Chemical messengers interacting with receptors
Anchors cells to the extracellular matrix

Question 21

What can normal bacterial flora do and what can it be disrupted by?

Answer 21

Protection against pathogenic bacteria
Aiding digestion
Vitamin production
Stimulation of immune response
Can be disrupted by:
Compromised immune system
Ageing
Antibiotic treatment
Prolonged hospitalisation

Question 22

Pathogenic and non-pathogenic bacteria

Answer 22

Pathogenic bacteria can cause or has the potential to cause disease or infection
Non-pathogenic bacteria do not cause disease

Question 23

Name 5 virulence factors

Answer 23

Factors that make bacteria pathogenic:
Entry into host
Antibiotic resistance
Toxin production
Immune evasion
Invasiveness

Question 24

How are viruses classified?

Answer 24

Viruses can’t be classified by disease so are classified by their nucleic acid

Question 25

Viral Replication and Protein Synthesis

Answer 25

Nucleic acid is copied and viral proteins are produced