lect 7/8: microbial metabolism

Question 1

define heterotrophs

Answer 1

use organic molecules as carbon sources which often also serve as energy sources

Question 2

define autotrophs

Answer 2

use CO2 as their sole/principal carbon source and must obtain energy from other sources

Question 3

define lithotrophs

Answer 3

use reduced inorganic substances

Question 4

what does glycolysis produce

Answer 4

At and reduces NAD+ to NADH while oxidizing glucose to pyretic acid

Question 5

what does the krebs cycle do

Answer 5

produces some ATP by substrate phosphorylation, reduces NAD+ and FAD, and gives off CO2

Question 6

what is the final electron acceptor in aerobic respiration

Answer 6

Oxygen

Question 7

what is the final electron acceptor in anaerobic respiration

Answer 7

different exogenous acceptor (besides oxygen)

Question 8

how is ATP synthesized for fermentation

Answer 8

substrate-level phosphorylation

Question 9

where does the embden-meyerhof pathway occur

Answer 9

cytoplasmic matrix

Question 10

what are the 2 phases of EM pathway

Answer 10

six carbon phase and 3 carbon phase

Question 11

what does the oxidation step of the EM pathway produce

Answer 11

NADH

Question 12

what is the net outcome of the EM pathway

Answer 12

2 pyruvate, 2ATP, 2NADH and 2H+

Question 13

what uses the entner-duodoroff pathway

Answer 13

soil bacteria and a few gram negative bacteria

Question 14

what is the yield per glucose in the ED pathway

Answer 14

1 ATP, 1 NADPH, and 1 NADH

Question 15

what is the main product in the pentose phosphate pathway

Answer 15

NADPH

Question 16

what is the net outcome for the PPP

Answer 16

6CO2, 12 NADPH, and 12H+Pi

Question 17

what is the major role of the TCA cycle

Answer 17

source of carbon skeletons for use in biosynthesis

Question 18

what does each acetyl CoA molecule generate

Answer 18

2 molecules CO2, 3 molecules NADH, one FADH2, and one GTP

Question 19

how many ATP molecules are synthesized directly from oxidation of glucose to CO2

Answer 19

4 ATP molecules

Question 20

where does ETC occur in bacteria and archae

Answer 20

plasma membrane

Question 21

what is the upper branch of the ETC in bacteria

Answer 21

stationary phase and low aeration

Question 22

what is the lower branch of the ETC in bacteria

Answer 22

log phase and high aeration

Question 23

what does ATP synthase use to catalyze ATP synthesis

Answer 23

PMF down gradient

Question 24

define dissimilatory nitrate reduction

Answer 24

use of nitrate as terminal electron acceptor, making it unavailable to cell for assimilation or uptake

Question 25

define denitrification

Answer 25

reduction of nitrate to nitrogen base (in soil, causes loss of soil fertility)

Question 26

what are triglycerides hydrolyzed to and by what

Answer 26

hydrolyzed to glycerol and fatty acids by lipases

Question 27

define protease

Answer 27

hydrolyzes protein to amino acids

Question 28

define deamination

Answer 28

removal of amino group from amino acid