Cellular Metabolism II

Question 1

Mitochondrion

Answer 1

Outer membrane, inner membrane, mitochondrial matrix is within inner membrane, intermembrane space is between outer and inner membrane

Question 2

Pyruvate decarboxylation location

Answer 2

Mitochondrial matrix

Question 3

Pyruvate decarboxylation start and end products

Answer 3

Pyruvate from glycolysis is brought into the mitochondrial matrix via secondary active transport with protons. Pyruvate decarboxylase complex (PDC) catalyzes reaction between pyruvate and coenzyme A. Produces 1 Acetyl-CoA, 1 CO2 and 1 NADH.

Question 4

Krebs cycle location

Answer 4

Mitochondrial matrix

Question 5

Krebs cycle oxygen requirement

Answer 5

Aerobic, requires oxygen

Question 6

Krebs cycle - important step

Answer 6

Acetyl-CoA merges with oxaloacetate to form citrate.

Question 7

Krebs cycle end products

Answer 7

1 round gives 3 NADH (electron carrier), 1 FADH2 (electron carrier), 1 GTP (or ATP), 2 CO2

Question 8

Electron transport chain location

Answer 8

Inner membrane of mitochondria, which has many folds to increase surface area to increase ETC

Question 9

Electron transport chain oxygen requirement

Answer 9

Aerobic, requires oxygen, oxidative phosphorylation occurs. Electron carriers become oxidized

Question 10

Electron transport chain - electron carriers

Answer 10

Electron carriers made from glycolysis, pyruvate decarboxylation and Kreb’s cycle are oxidized by oxidative phosphorylation during this process

Question 11

Electron transport chain - carrier proteins

Answer 11

Receive electrons from electron transporters and use their energy to pump H+ against the concentration gradient into the intermembrane space.

Question 12

Electron transport chain - final electron acceptor

Answer 12

Oxygen

Question 13

Electron transport chain - final (by)product

Answer 13

Final electron acceptor oxygen combines with H+ to make H2O

Question 14

Electron transport chain - ATP synthase

Answer 14

Makes ATP using the proton motive force. Catalyzes ADP + Pi to ATP. ATP is made into the mitochondrial matrix

Question 15

Electron transport chain - Proton motive force

Answer 15

H+ gradient, pH and electrical gradient. More H+ = more acidic = lower pH

Question 16

Electron transport chain - NADH vs FADH2

Answer 16

NADH makes 3 ATP, FADH2 makes 2 ATP. More protons are pumped across per NADH molecule than FADH2, because NADH enters the chain earlier at complex I, but FADH2 enters at complex II

Question 17

Electron transport chain - Coenzyme Q/Ubiquitone

Answer 17

Carrier protein, can be fully oxidized and fully reduced in the process of passing electrons between the complexes

Question 18

Electron transport chain - Cytochrome C

Answer 18

Carrier protein, has iron atom that captures and releases electron between complex III and complex IV

Question 19

Total Energy from cellular respiration

Answer 19

1 glucose molecule give 36 ATP

Question 20

Fermentation

Answer 20

It is how cells deal with lack of oxygen but still make ATP. Regenerates NAD+

Question 21

Alcoholic fermentation location

Answer 21

Occurs in fungi (yeast), plants, bacteria.

Question 22

Alcoholic fermentation steps

Answer 22

Converts pyruvate from glycolysis into acetaldehyde, then into ethanol. Releases 1 CO2 and oxidizes 1 NADH to 1 NAD+.

Question 23

Alcoholic fermentation final electron acceptor

Answer 23

Acetaldehyde, receives electrons from NADH. Acetaldehyde is then reduced to ethanol

Question 24

Alcoholic fermentation NAD+

Answer 24

NAD+ generated can be used to continue glycolysis

Question 25

Lactic acid fermentation location

Answer 25

Skeletal muscle cells

Question 26

Lactic acid fermentation steps

Answer 26

Reduces pyruvate from glycolysis into byproduct called lactate, and this process oxidizes NADH to NAD+.

Question 27

Lactic acid fermentation - Lactate and Cori cycle

Answer 27

Lactate is weak base. Corresponding weak acid is lactic acid. Lactate enters blood stream and goes to liver. In liver, lactate is converted to glucose, which enters blood stream to be used by cells to produce more ATP in glycolysis

Question 28

Lactic acid fermentation NAD+

Answer 28

NAD+ generated can be used to continue glycolysis and make more ATP