Lab 1 - Basic Techniques

Question 1

Autoclave

Answer 1

Steam pressure sterilizer

(121C at 15 psi for 15 mins +)

Question 2

moist heat

Answer 2

better sterilizer than dry heat because water is a better conductor of heat than air is

Question 3

medium

Answer 3

nutrient source used for culturing microbes

Question 4

media classified by

Answer 4

physical state, nutritional or chem composition and function or use

Question 5

agar

Answer 5

usual solidifying agent

complex polysaccharide extracted from red algae

Question 6

sloppy agar

Answer 6

medium that denotes agar at a lower concentration

• organisms can disperse more
• mostly used in motility studies

Question 7

media physical state

Answer 7

solid (plate or slant) or liquid (broth)

Question 8

media nutritional composition

Answer 8

minimal or rich

Question 9

minimal nutritional composition

Answer 9

supplies salts and mono/di-saccharrides
chemically defined … exact amounts needed

Question 10

rich media

Answer 10

wide variety of nutrients

no need to synthesize building blocks (amino acids)

Question 11

SAR11 and rich media

Answer 11

can be poisoned

it is adjusted to low nutrient enviros

Question 12

oligotroph

Answer 12

organism that can live in very low nutrient enviro

Question 13

copiotroph

Answer 13

org. live in very nutrient rich enviros

Question 14

Media - function

Answer 14

selective, differential, selective-differential and all purpose

Question 15

selective media

Answer 15

supports growth of one, inhibits unwanted orgs

Question 16

Inhibitory compounds

Answer 16

inhibit growth of unwanted organisms

ex. dyes (crystal violet - triphenyl methane dye… inhibits gram+ organisms, antibiotics, etc.)

Question 17

differential mediums

Answer 17

supports growth of multiple organisms but enables user to distinguish them.

Question 18

selective-differential media

Answer 18

supports growth of a particular group of organisms and also differentiates bacterial types within that group.

Question 19

all purpose medium

Answer 19

supports a wide range of organisms indiscriminately

e.g. nutrient agar

Question 20

dehydrated media

Answer 20

like boxed cake mix

Question 21

inoculations

Answer 21

aseptic transfer of cultures

Question 22

inoculum

Answer 22

substance used for inoculations

Question 23

‘streak’ plate technique

Answer 23

used to obtain isolated colonies