Microbiology

Question 1

Name 5 microorganisms/ infection agents in decreasing size

Answer 1

parasites, fungi, bacteria, viruses and prion proteins

Question 2

what are prion proteins

Answer 2

infectious proteins that have no DNA or RNA

Question 3

Why does surgical equipment have to be destroyed after being used on a patient with a prion disease?

Answer 3

because prion proteins cN NOT VE RELIbly removed by sterilisation or disinfection

Question 4

what do eukaryotic cells contain

Answer 4

Nucleus, nucleolus, plasma membrane, mitochondria, ribosome, Golgi apparatus, endoplasmi reticulum

Question 5

what are eukaryotic cells

Answer 5

fungi and protozoa

Question 6

what are prokaryotic cells

Answer 6

bacteria

Question 7

what do prokaryotic cells contain

Answer 7

ribosomes, DNA, cell envelope, cell membrane

Question 8

what colour do gram neg cells stain

Answer 8

pink

Question 9

what colour do gram positive cells stain

Answer 9

purple

Question 10

why do gram positive cells stain purple

Answer 10

because they have a thick layer of peptidoglycan which retains purple stain

Question 11

why do gram neg cells stain pink

Answer 11

only have a thing layer of peptidoglycan

Question 12

why is it important to know the gram stain

Answer 12

many antibiotics act on bacteria cell wall, o it is important to know if the cell wall is arm positive or gram negative to know which antibiotic will work.

Question 13

what organisms don’t stain well

Answer 13

mycobacterium tuberculosis (organism that causes tb) and treponema palladium (organism that causes syphilis)

Question 14

what is needed for bacteria to grow

Answer 14

food, moisture, correct temp and correct pH

Question 15

Bacterial Growth phases

Answer 15

lag phase, log phase, stationary phase and death phase

Question 16

lag phase

Answer 16

bacteria only present in small numbers and DNA has to be replicated

Question 17

log phase

Answer 17

bacteria can multiply exponentially

Question 18

stationary phase

Answer 18

maintains constant levels

Question 19

death phase

Answer 19

resources begin to run out and some bacteria die

Question 20

3 main types of atmosphere bacteria grows in

Answer 20

aerobic, microaerophilic and anaerobic

Question 21

aerobic growth

Answer 21

growth in presence of oxygen

Question 22

microaerophilic

Answer 22

atmosphere with a reduced concentration of oxygen and enriched with CO2

Question 23

anaerobic

Answer 23

no oxygen present in atmosphere

Question 24

how often can bacteria replicate in ideal growth conditions?

Answer 24

every 20 minutes

Question 25

why do some bacteria make us ill?

Answer 25

gram positive bacteria produce exotoxins, usually produced inside the cell and exported from it. Gram negative bacteria produces endotoxins which is part of the bacterial wall.

Question 26

what type of cell produces spores

Answer 26

gram positive

Question 27

how can you identify different bacteria

Answer 27

gram stain reaction, atmosphere they grow in, shape and other criteria such as biochemical tests

Question 28

pathogen

Answer 28

harmful organism

Question 29

commensal

Answer 29

organism that is part of the normal flora

Question 30

opportunistic pathogen

Answer 30

an organism that will probably only cause infection in an immune-compromised individual

Question 31

contaminant

Answer 31

an organism that has got into a culture by accident

Question 32

pathogenicity

Answer 32

the ability of a microorganism to produce disease

Question 33

virulence

Answer 33

the degree of pathogenicity of an organism

Question 34

what kills fungi

Answer 34

anti fungal treatment , not antibiotics

Question 35

sterilisation

Answer 35

destruction and removal of 99.9% of micro organisms and spores

Question 36

disinfection

Answer 36

removal or destruction of pathogenic micro organisms enough to make an item safe

Question 37

how to disinfect something

Answer 37

use hot water or chemicals