Unit 3 Culture: Terminology

Question 1

define simple diffusion

Answer 1

only water, O2, CO2 and lipids cross cell envelope by concentration gradient

Question 2

define active transport

Answer 2

transport of solutes by carrier proteins, nrg dependent often against [gradient]

Question 3

define constitutive enzymes

Answer 3

produced by the cell independent of the medium in which it is growing

Question 4

define inducible enzyme

Answer 4

produced in response to a stimulus (may be presence or absence of substrate)

Question 5

define constitutive-inducible enzyme (gene/gene product)

Answer 5

alway produced at low levels but production is increase in presence of stimulus

Question 6

define fastidious

Answer 6

vary in their nutritional requirements and do not grow in ambient air

Question 7

define semi fastidious

Answer 7

require blood to grow well (often benefits from increased C02)

Question 8

define non fastidious

Answer 8

grow in the absence of blood on base media in ambient air

Question 9

define mesophile

Answer 9

optimum growth temp is 25-45 C

Question 10

define routine incubation

Answer 10

Ambient air 78N 21O and 0.03 co2. 35 degrees

Question 11

characteristics of obligate aerobe

Answer 11

grow in presence of free O2
require O2 for metabolism
routine aerobic incubation

Question 12

define facultative anaerobe

Answer 12

grow in presence or absence of O2.

Question 13

define obligate anaerobe

Answer 13

varies in sensitivity to O2 can be aerotolerant, moderate anaerobe or strict anaerobe

Question 14

define aerotolerant

Answer 14

benefits from growth in Co2 incubator, don’t use O2 but can tolerate it. 15-19 02

Question 15

define moderate anaerobe

Answer 15

Oxygen less than 3 percent therefore Can’t survive in co2 incubator or routine

Question 16

define strict anaerobe

Answer 16

Dies in presence of 02 even 10 mins of 0.5 % o2 lethal

Question 17

characteristics of capnophile

Answer 17

grow best in increase C02 (5-10%)

Question 18

characteristics of microaerophile

Answer 18

grow best in low oxygen tension (5-10%) and increase CO2 (8-10%)

Question 19

define isotonic

Answer 19

maintenance of osmotic pressure. 0.5 %NaCl

Question 20

characteristics nutrient (basal) media

Answer 20

supports non fastidious org, does not enhance or inhibit bacterial

Question 21

characteristics of enriched media

Answer 21

supports more fastidious org by addition of special nutrients but no added inhibitory ingredients

Question 22

characteristics of selective media

Answer 22

inhibitory agents suppress growth of some, selects for other particular org

Question 23

characteristics of differential media

Answer 23

factors added to aid in distinguishing diff bacteria growing on same plate

Question 24

what is alpha hemolysis

Answer 24

greenish colony not hemolysis

Question 25

what is beta hemolysis

Answer 25

complete hemolysis

Question 26

what is gamma hemolysis

Answer 26

no hemolysis

Question 27

e.g. of constitutive enzyme

Answer 27

enzymes involved in glycolysis

Question 28

e.g. of inducible enzymes

Answer 28

galactosidase is produced in response to lactose

Question 29

define group translocation

Answer 29

requires org and molecules are modified for transport. purines, fatty acids etc

Question 30

Describe candle jars

Answer 30

Reduced o2 to 5 percent. Generates 3 percent c02