Chapter 5 (Book)

Question 1

general result of Arrhenius eqution

Answer 1

growth rate doubles for every 10C rise in temp

Question 2

high temp causes proteins to ________

Answer 2

denature

Question 3

low temp causes a decrease in…

Answer 3

membrane fluidity and mobility of enzymes

Question 4

psychrophilic protein adaptation

Answer 4

more flexibility and require less heat to function

downside is they denature at lower temps

Question 5

psychrophilic lipid adaptation

Answer 5

more unsaturated FA so membrane is more fluid

downside is that at higher temp the membrane is too flexible and fails to maintain integrity

Question 6

psychrophilic cryoprotectants

Answer 6

proteins like trehalose that depress the freezing point so they don’t freeze

Question 7

thermophile adaptations

Answer 7

more H-bonding

chaperones that refold proteins after denaturation

DNA-binding proteins that stabilize DNA

enzymes to super supercoil DNA

Question 8

thermophile membrane adaptations

Answer 8

saturated FA for more h-bonding

archaea do a monolayer

Question 9

heat-shock response

Answer 9

activates stress response genes

make chaperones to maintain protein shape

enzymes change lipids in the memb.

Question 10

many barophiles are ________

Answer 10

psychrophilic b/c temp at ocean floor is 2C

barophilic thermophiles exist in vents

Question 11

barophilic adaptations

Answer 11

must maintain flexibility so many unsat FA

pressure-adapted ribosomes

Question 12

bacteria in a hypertonic solution do what

Answer 12

import/synthesize compatible solutes - small molecules that don’t disrupt cell metabolism

attempt to balance the osmolarity

Question 13

bacteria in hypotonic solutions

Answer 13

press-sensitive channels leak solutes out

Question 14

why do halophiles keep a low intracellular Na+ concentration

Answer 14

solutes are moved into the cell by symport with Na

special pumps exchange Na out for K in

Question 15

alkaliphile adaptations

Answer 15

sodium motive force (provides energy for flagella, symport)

use a Na+ out H+ in pump

H+ in drives ATP synthase

Question 16

aerobic respiration

Answer 16

the use of O2 as the terminal electron acceptor

Question 17

aerotolerant anaerobe

Answer 17

only uses fermentation for energy

possesses enzymes to deal with ROS

Question 18

starvation activates _______ genes

Answer 18

survival

Question 19

eutrophication

Answer 19

sudden infusion of a large amount of a formerly limiting nutrient

causes a bloom of microbes

threatens existence of some microbes

Question 20

how do organisms that synthesize antibiotics avoid getting killed by their own antibiotics

Answer 20

the producing organism may lack the target molecule

if the antibiotic enters the organism, it modifies it