Exercise 21 Carbohyrdate Fermentation

Question 1

catabolize

Answer 1

metabolize, release energy and simpler carbon compounds

Question 2

fn of permease

Answer 2

transport membrane for the uptake of mono and discaccharides

Question 3

two forms of catabolism

Answer 3

fermentation and respiration

Question 4

respiration uses

Answer 4

O2 as TEA in ETC

Question 5

fermentation uses

Answer 5

organic compound as TEA without use of ETC

Question 6

purpose of fermentation

Answer 6

reoxidize the NADH that has been produced in a pathway like glycolysis

Question 7

most carb. fermentation uses… at TEA

Answer 7

oyruvate, pyruvate derivates or phosphoenolpyruvate

Question 8

Phenol Red carb. broth fn identifies

Answer 8

the general end porduct of fermentation

Question 9

how is Phenol Red Broth differential medium

Answer 9

single type of carb. used as the sole ferementable nutrient

Question 10

what are nonfermentable nutrients in phenol red

Answer 10

peptone and beef extract

Question 11

phenol red changes colour to what and when

Answer 11

red when pH above 7.4. yellow when pH below 6.8

Question 12

how does phenol red change colours

Answer 12

acid production changes it to yellow, deamination of peptone aa will produce ammonia turns pink/red

Question 13

purpose of durham tube

Answer 13

traps gas produced if any

Question 14

why are reading after long incubation unreliable for phenol red

Answer 14

reversion, org ferments a carb until source is exhausted and then switches to deamination. false -ive

Question 15

why readings after short incubation unreliable for phenol red

Answer 15

pH hasn’t changed, pink colour indicates substrate not fermented and peptone aa likely deaminated