Pathology

Question 1

Name the structural parts of a bacteria.

Answer 1

1. Capsule
2. Pilli/fimbriae
3. Flagellae.
4. Spores
5. Slime
6. Cell wall.

Question 2

What does the capsule do?

Answer 2

Protects the cell from phagocytosis and dessication.

Question 3

What do Pilli/fimbriae do?

Answer 3

1. Contain lectin which recognise and bind to oligosaccharide units on host cell.
2. Involved in appendage which is useful in bacterial conjugation.

Question 4

Describe flagellum.

Answer 4

20nm thick helical tube.

Question 5

Which bacteria has a lot of pilli?

Answer 5

E. coli.

Question 6

Name 4 common bacteria with flagella.

Answer 6

1. Vibrio cholera.
2. Helicobacter pylori.
3. Campylobacter jejuni.
4. E. coli.

Question 7

What is a spore?

Answer 7

1. Unit of asexual reproduction.

2. Allows survival under unfavourable conditions.

Question 8

Name 5 common disease caused by spore bacteria.

Answer 8

1. Botulism.
2. Gas gangrene.
3. Tetanus.
4. Food poisoning.
5. Anthrax.

Question 9

What is slime used to protect against?

Answer 9

1. Immune attack.

2. Antibiotics.

Question 10

What bacteria will secrete slime?

Answer 10

Bacteria growing in biofilm.

Question 11

What are the two sugar residues which alter in peptidoglycan?

Answer 11

1. N-acetylglucosamine.

2. N-acetylmuramic acid.

Question 12

Explain the importance of LTA.

Answer 12

1. Provides cell rigidity.

2. Recognised by host immune cells.

Question 13

Explain the importance of LPS.

Answer 13

1. Essential for outer membrane function.
2. Causes immune and inflammatory responses.
3. Produces endotoxins.

Question 14

What is the recipient cell in bacterial recombination referred to as?

Answer 14

F+ cell.

Question 15

Three types of bacterial shapes.

Answer 15

1. Cocci
2. Bacilli.
3. Helical.

Question 16

What essentially is a virus?

Answer 16

A nucleic acid enclosed in a protein shell.

Question 17

Name three key structures in a virus.

Answer 17

1. Capsid.
2. Envelope (sometimes)
3. Spikes (sometimes)

Question 18

Example of a virus with an envelope.

Answer 18

Herpes virus.

Question 19

What are spikes?

Answer 19

Glycoprotein projections from the envelope which are highly antigenic.

Question 20

Example of a virus with spikes.

Answer 20

Adenovirus.

Question 21

Name the six stages in viral replication.

Answer 21

1. Adsorption.
2. Penetration.
3. Replication.
4. Assembly
5. Maturation.
6. Release

Question 22

Explain how naked viruses (no envelope) are released.

Answer 22

1. Occurs at site of nucleic acid replication.
2. Viral enzymes break down host cell wall.
3. RNA viruses are released as they are produced.
4. DNA viruses are releases when host cell autolysis.
5. DNA viruses are expelled as inclusion bodies.

Question 23

Explain how enveloped viruses are released.

Answer 23

1. Virus migrates to plasma membrane.
2. Capsid forms from budding of plasma membrane.
3. Slow release of viral particles.
4. No inclusion bodies.

Question 24

Give an example of replication of an enveloped virus.

Answer 24

HIV budding.

Question 25

What are the 4 groups of protozoa?

Answer 25

1. Sporozoa. 2. Flagellates. 3. Amoeba. 4. Ciliates

Question 26

4 common infections of protozoa.

Answer 26

1. Malaria. 2. Giardiasis. 3. Toxoplasmosis. 4. Cryptosporidiosis.

Question 27

Is yeast single celled?

Answer 27

Yes.

Question 28

4 common fungal infections.

Answer 28

1. Candidiasis 2. Cryptococcosis. 3. Aspergillosis. 4. Ringworm

Question 29

What are helminths?

Answer 29

Parasitic worms.

Question 30

Three groups of helminths.

Answer 30

1. Cestoda. 2. Trematoda. 3. Nematoda.

Question 31

What are cestoda, trematoda and nematoda?

Answer 31

1. Cestoda = tapeworms. 2. Trematoda = flukes. 3. Nematoda = round worms.

Question 32

Give three examples of helminth diseases.

Answer 32

1. Tape worm infections. 2. Schistosomiasis. 3. Trichiuriasis.

Question 33

Four criteria for Koch's postulates.

Answer 33

1. Bacteria must be present in every case. 2. Bacteria must be isolated and be able to grow in pure culture. 3. Bacteria must be able to reproduce when injected into host. 4. Bacteria must be recoverable from the experimentally infected host.

Question 34

What does the innate immune response consist of?

Answer 34

1. Normal microbiota 2. Physical barriers. 3. Chemical barriers. 4. Phagocytic cells.

Question 35

Explain the importance of normal microbiota.

Answer 35

1. Compete with pathogens for colonisation sites. 2. Produce antibiotic substances to inhibit growth. 3. Produce toxic metabolic substances. 4. May alter pH.

Question 36

Name 4 physical barriers?

Answer 36

1. Skin 2. Mucomuciliary clearance. 3. Flushing (passing of urine). 4. Peristalsis.

Question 37

Name 4 chemical barriers?

Answer 37

1. Mucus. 2. Gastric acid. 3. Antimicrobial proteins 4. Plasma proteins.