Mircobiology (MCQ)

Question 1

branches of microbiology

Answer 1

.general microbiology- basics of microbiology structure, growth, diversity

.immunology-immune system

. food microbiology- study microbes that make food, drink-and when its not cooked properly

.industrial microbiology-microbes to produce products

.biotechnology-manipulation of organisms to form useful products

Question 2

light microscope

Answer 2

1. sample preparation-thin film for non living or motile cell, dividing cell
2. source of light- ordinary light
3. 2 lenses-objective lens and ocular lens (eyepiece)
4. final image- viewed directly by eye and it is coloured

.poor magnification and resolution
.long wavelength of white light
.uses live specimen

Question 3

wavelength

Answer 3

distance between successive crests of a wave

Question 4

resolution

Answer 4

distance between 2 points of specimen that can be distinguished as 2 separate objects

Question 5

magnification equation

Answer 5

M of objective lens x M of eyepiece lens
OR
M= I/A

Question 6

electron microscopes

Answer 6

.short wavelength of electrons
.uses magnets instead of lenses to focus on beam onto specimen
.image is projected onto photographic paper to make a grey scale image

Question 7

TEM (electron microscope)

Answer 7

1. sample prep- must be completely dry w/heavy positive ions
2. source of light- beams of electrons
3. 2D image not coloured on fluorescent screen
4. greater range of magnification and improved resolution
5. expensive used in research-need large physical space and use dead specimen

Question 8

SEM (electron microscope)

Answer 8

1. sample prep- must be completely dry and coated in heavy gold ions
2. source of light- beams of electrons
3. 3D image in black and white
4. highest magnification and resolution
5. expensive and use dead specimen

Question 9

unit conversions-
SMALL-BIG=DIVIDE
BIG-SMALL=MULTIPLE

Answer 9

1m= 1000mm
1mm=1000um
1um=1000nm

Question 10

spontaneous generation (ABOGENSIS)

Answer 10

.scientists believed that living organisms develop from non-living matter

.believed that there is a mysterious force that lead to formation of animals (Miasma)

Question 11

biogenesis

Answer 11

.scientists did not believe in that theory and believed that lifeforms come from other life forms (life makes life)

Question 12

Francesco Redi (1668)
(FOR BIOGENISIS)

Answer 12

.showing that meat did not produce maggots it was flies

Question 13

John Needman (1745)-STUDIED ON SPONTANEOUS GENRATION (study not valid)

Answer 13

.He prepared various broth jars

.He boiled them to eliminate any microbes present

.He left them uncovered at room temperature to cool and he sealed them

.After few days infusion become cloudy

.He thought that this proved theory of spontaneous generation- microbes generated spontaneously from non-living broth

Question 14

problems with John Needman’s experiment

Answer 14

.boiling time was insufficient to kill anyendosporesof microbes

.cooling of flasks left open to air could cause microbial contamination

.did not use propersterile technique

Question 15

Lazzaro Spallanzani (1745)
(DISPROVED JOHN NEEDMAN-FOR BIOGENESIS)

Answer 15

.disagreed w/Needham because Needham left jars exposed

.he repeated experiment but sealed all jars well

.result= no growth

Question 16

Louis Pasteur (1859)

Answer 16

.he squashed idea of spontaneous generation and approved germ theory (that turbidity is caused by microbes)

.Pasteur developed swan necked flasks

.Flask traps dust and microbes

Question 17

germ theory

Answer 17

.certain diseases are caused by invasion of body by microorganisms, organisms too small to be seen except through microscope

Question 18

Ignaz Semmelweis (1847)
(SAVIOUR OF MOTHERS)

Answer 18

.maternal mortality rate was decreased by introduction of handwashing w/chlorinated lime solution

.discovered wonders of now-basic hygienic practice as a way to stop spread of infection in 1847, during an experiment in Vienna hospital’s

Question 19

Joseph Lister

Answer 19

.carried out first antiseptic surgery w/carbolic acid

.prevention of infection in wounds during and after surgery

.first to apply science of Germ Theory to surgery

.Lister’s Antisepsis System is basis of modern infection control-principles made surgery safe and continue to save countless lives

Question 20

John Snow (FATHER OF EPIDEMOLOGY)

Answer 20

.proved that cholera outbreak is spread by contaminated water

.conducted pioneering investigations on cholera epidemics in England and particularly in London in 1854 in which he demonstrated that contaminated water was key source of epidemics

Question 21

Edward Jenner

Answer 21

.discovered small pox vaccine

.vaccination w/cowpox virus can protect a person from smallpox infection

Question 22

Robert Knoch

Answer 22

.built on Pasteur’s work by proving that particular organism is cause of disease or specific diseases caused by a specific microbe

Question 23

Koch’s theory/postulates

Answer 23

1. Be found in all cases of the disease examined (identify)
2. Be prepared and maintained in a pure culture (isolation)
3. Be capable of producing the original infection, even after several generations in culture (introduce)
4. Be retrievable from an inoculated animal and cultured again (re-isolate)