Catabolic Reactions Cont’d

Question 1

What is the 1st step for the Kreb cycle ?

Answer 1

Preparation occurs in the mitochondria and uses 3 carbon pyruvic acid to convert to 2 carbon acetyl coA with 1 NADH formed

Question 2

What is the kreb cycle?

Answer 2

Repetitive cycle involving 9 carbon compounds: Acetyl group (2 carbons) + oxaloacetic acid (4 carbons) + citric acid (6 carbon) that Produces lot of energy and releases CO2 and NADH + 1 FADH2 and 1GTP formed

Question 3

What is the Glyoxylate cycle?

Answer 3

Catabolism of C2-C3 organic acids typically involves production of oxaloacetate ; also a variation of the citric acid cycle

Question 4

Describe the Electron transport and chemiosmotic ATP synthesis

Answer 4

NADH and FADH2 is converted into ATP, Electrons are released to electron transport system and provide energy for active transport of H+ ions (separates protons from electrons to create an electron potential) ; oxygen is the terminal electron acceptor that ends up making water

Question 5

What is the last step for aerobic respiration?

Answer 5

Use of O2

Question 6

What is anaerobic respiration and some examples of it?

Answer 6

Less energy is released with the use of electron acceptors other than oxygen; Dependent on electron transport, generation of a proton motive force, and ATPase activity; examples include nitrate (NO3-), ferric iron (Fe3+), sulfate (SO42-), carbonate (CO32-)

Question 7

What are facultative anaerobes? Name some examples for them.

Answer 7

They use oxygen when it’s around, but use nitrate if there’s no oxygen. Examples include Pseudomonas sp Moraxella sp, Bacillus sp

Question 8

What are strict anaerobe? Name an example.

Answer 8

Use sulfate and hydrogen sulfide gas; Desulfovibrio sp

Question 9

What is Fumarate to succinate and what cycle does it use? Name some examples.

Answer 9

An organic electron acceptor that uses the Kreb cycle; Proteus sp,Enterococcus sp, Escherichia coli

Question 10

Where is methanogenic bacteria found and what compound is it made from?

Answer 10

Found an intestinal tracks, sewage plants, and ruminants; carbonate

Question 11

What does Acidophilic use and name an example.

Answer 11

Uses iron to grow in concentrated sulfuric acid; Thiobacillus feroxidans

Question 12

Describe chemolithotrophy and name some examples of it

Answer 12

Uses inorganic chemicals as electron donors that typically need oxygen and is autotrophic (uses CO2 as carbon source) Begins with oxidation of inorganic electron donor and uses electron transport chain and proton motive; Examples include hydrogen sulfide (H2S), hydrogen gas
(H2), ferrous iron (Fe2+), ammonia (NH3);