Bacteriology

Question 0

Define prokaryotic cells?

Answer 0

Prokaryotic cells don’t have a nucleus and are unicellular.

Question 1

Define eukaryotic cells?

Answer 1

Eukaryotic cells are usually multicellular an have a defined nucleus and are usually found in plants and animals.

Question 3

Describe the shape of a “cocci” bacteria?

Answer 3

Circular spherical and or grouped in clusters, pairs, cubical groups.

Question 4

Describe the shape of “Spirochaetes”?

Answer 4

Flexible spiral shape with motile filaments.

Question 5

Name 3 examples of bacilli bacteria?

Answer 5

Clostridium, bacillus, salmonella, escherichia, brucella, myobacterium.

Question 6

What are chains of cocci bacteria known as?

Answer 6

Streptococci

Question 7

Describe the clinical signs of deep pyoderma and name the primary pathogen?

Answer 7

Pain, crusting, malodour, ulceration of skin, exudation of pus and blood. Staphylylococcus pseudintermedius.

Question 8

Describe the nursing care that can be given to a rabbit suffering from pasteurellosis?

Answer 8

Isolate the rabbit, keep eyes and nose clean; apply barrier cream. Provide a hide box, hay. Tempt to eat. Groom.

Question 9

Describe how campylobacter is transmitted?

Answer 9

Faecal-oral transmission, via food and water born.

Question 10

Define the pathogens Leptospira canicola?

Answer 10

Dogs are the main carrier of Leptospira canicola which primarily affects the kidneys. Symptoms vary from mild to severe with kidney failure and sudden death in the worst cases. Dogs can also be carriers of Leptospira canicola and again the bacterium can be passed out in urine which puts other dogs and people at risk.

Question 11

10. Define the pathogens Leptospira icterohaemorrhagiae?

Answer 11

Rats are the main carrier. This bacterium is transmitted to dogs either directly through infected urine or indirectly via contact with contaminated water (ie swimming in rivers, ponds etc). Dogs that have been infected may go on to become carriers of the disease and the bacterium can then be passed out in their urine putting other dogs and people at risk. Symptoms can range from mild to severe with liver failure and sudden death in the worst cases.

Question 12

Define Pilli?

Answer 12

Hair like structures used for attachment.

Question 13

Define Flagellum?

Answer 13

Whip like structures used for mobility.

Question 14

Describe the functions of the cell membrane?

Answer 14

Transport of nutrients. Production of components of ATP. Attachment site for chromosome and plasmids. Biosynthetic enzymes. Photosynthetic bacteria have photosynthetic structures in the cell membrane.

Question 15

When stained with Gram stain, which type of bacteria will be stained pink?

Answer 15

Gram Negative.

Question 16

Gram Negative bacteria stains pink, why does this occur?

Answer 16

Gram negative bacteria have an extra layer of lipid, comprising an outer membrane and hence do not take up the purple stain.

Question 17

Describe endospores?

Answer 17

Highly durable survival form which can survive in unfavourable conditions. They can remain viable for years. They can survive extreme heat, pH, desiccation, chemicals, such as some disinfectants and UV.

Question 18

Describe the requirements for bacteria to replicate?

Answer 18

Nutrients. Correct temperature. Correct pH. Water. Correct gaseous mix.

Question 19

Describe how a phage will transfer bacteria DNA?

Answer 19

Phage inject DNA into bacterial cell. Fragments of bacterial DNA incorporated into phage. Bacterial cell lysed and new phage released. Phage containing bacterial DNA infects a new cell and the genes from 1st bacteria is incorporated into new host.

Question 20

What is meant by the term obligate pathogen?

Answer 20

A pathogen that is always associated with disease.

Question 21

Describe endotoxin?

Answer 21

Part of the cell envelope of Gram –ve bacteria Released when cells die or disintegrate Responsible for non-specific signs such as fever At high levels may cause endotoxic shock.

Question 22

Describe Exotoxin?

Answer 22

Exotoxins are proteins produced mainly by Gram +ve bacteria. The body produces antibodies known as antitoxins Exotoxins can be treated by chemicals e.g. formaldehyde – called toxoids.

Question 23

Which test will be most appropriate when choosing an antibiotic for treatment of a bacterial infection?

Answer 23

Culture and sensitivity.

Question 24

Which type of moist heat can be used to control bacteria?

Answer 24

Autoclave sterilisation or tyndallisation.

Question 25

What type of chemical agent can be used to control bacteria in a dog bite?

Answer 25

An antibacterial wash such as chlorhexidine.