Week 2

Question 1

microorganism

Answer 1

microscopic organism consisting of a single cell or cell cluster including the viruses

Question 2

bacteria and fungi

Answer 2

-They are essential to maintaining a balance between living organisms and chemicals in the environment

Question 3

microbiology

Answer 3

the study of microograisms

Question 4

mycology

Answer 4

study of fungi

Question 5

parasitology

Answer 5

-study of protozoa and parasitic worms

Question 6

-virology-

Answer 6

the study of viruses

Question 7

immunology-

Answer 7

the study of immunity and immune system

Question 8

Koch’s postulates

Answer 8

the organism should be constantly present in animals suffering from the disease and should not be present in healthy animals./

2- organism must be cultivated in a pure culture away from the animal body

3-the culture when, inoculated into susceptible animals. should initate the charcteristic disease symtoms

4- the organsim should be re isolated from the disease.

Question 9

bioremediation

Answer 9

-the use of microbes to clean up contaminated soil and groundwater, for example. Breaking down cyanite to improve the health of patients

Question 10

Carl Woese’ classification:

Answer 10

Bacteria-cell walls contain peptidoglycan(murein)

archaea-cell walls when present lack peptidoglycan

Eukaraya-includes protists, fungi, plants and animals

Question 11

Prokaryotes:

Answer 11

-Unicellular microorganisms, genetic material not enclosed with a true nucleus

-includes bacteria and archaea

Question 12

Shapes of micrbobes

Answer 12

Bacillus(rod-like)

Coccus(spherical ovoid)

Spiral(corkscrew, curved)

Question 13

Eukaryotes:

Answer 13

fungi-unicellular forms include yeasts and molds

-protozoa-unicellular, free living or parasitic

-algae-unicellular forms, photosynthetic eukaryotes

Question 14

Viruses:

Answer 14

-different from other microbial groups

-need electron microscope to visualize

-celluar organisms w nucleuic acid core sorrounded by a protein coat

-need to use cells.

Question 15

Characteristics of prokaryotes

Answer 15

-DNA is not enclosed in a membrane: one circular chromosome

-DNA is not associated with histones

-lack membrane bound organelles

-cell walls contain peptidoglycan and are complicated

-typically divide by the process of binary fission

Question 16

Pleomorphic=

Answer 16

”shape shifter”, having many shapes

Question 17

-micrometer-

Answer 17

typical unit of measurment for microorganisms

Question 18

light microscopy-

Answer 18

uses of visible light to observe speciments

Question 19

compound light microscopy

Answer 19

=total magnification acheived through a series of lenses

Question 20

-resoution=

Answer 20

ability of lenses to distinguish between two points a speicficed distance apart

Question 21

refractive index=

Answer 21

measure of light-bending ability of a medium

Question 22

-staining changes=

Answer 22

the refractive index to enhance visulzation

Question 23

-condenser focuses light =

Answer 23

to produce a brightfield illumination

Question 24

Darkfield microscopy

Answer 24

-image visulized using only REFLECTED LIGHT

-a specimen appears light against dark background

Question 25

Phase-contrast microscopy

Answer 25

allows detailed examination of internal strucutres in living microorganisms -based on wave nature of light rays -brings together both direct light rays and diffracted rays -image contains regions that are both in phase and out of phase

Question 26

DIC-differential interference contrast (DIC)

Answer 26

-uses two beams of light each split by seperate prisms -differences in refractive indexes generates contrast in the image -higher ressolution than phase contrast -image appears 3-d

Question 27

Fluorescense microscopy

Answer 27

the ability of substances to absorb wavelengths of light and emit lights of longer wavelengths -specimens can flourese naturally under UV or can be stained w fluorochromes

Question 28

Electron Microscopy:

Answer 28

-required to visualize structures smaller than 0.2 -beams of electrons has 100,000 times smaller wavelengths than light

Question 29

-transmission E.M

Answer 29

-magnifies objects 10,000 to 100,000 times -requires sectioning and fixing of specimen

Question 30

SCANNING E.M

Answer 30

-scans specimen with electron beam and magnifies 1000 to 10000x