Exam #3 - Chapter 7

Question 1

aerobic respiration

slide 9

Answer 1

final electron receptor is oxygen O₂

Question 2

autotrophs

Slide 3

Answer 2

able to produce their own organic molecules through photosynthesis

Question 3

anaerobic respiration

slide 9

Answer 3

final electron acceptor is an inorganic molecule (not O₂)

Question 4

heterotrophs

slide 3

Answer 4

live on organic compounds produced by other organisms

Question 5

fermentation

slide 9

Answer 5

final electron acceptor is an organic moleucle

Question 6

aerobic respiration formula

slide 10

Answer 6

C₆H₁₂O₆ + 6O₂ —-> 6CO₂ + H₂O
delta G = -686kcal/mol of glucose (standard conditions)
* energy is released in small steps (very slow)

Question 7

electron carriers

slide 12

Answer 7

• all carriers can be easily oxidized and reduced
• some carry just electrons, others carry electrons and protons
• NAD⁺ acquires 2 electrons and a proton to become NADH

Question 8

ATP and the 2 mechanisms for synthesis

slide 14

Answer 8

• Cells use ATP to drive endergonic rxns
  -ΔG = -7.3 kcal/mol
  1. substrate-level phosphorylation
• transfer phosphate group directly to ADP
• during glycolysis
  2. Oxidative phosphorylation
• ATP synthase uses energy from a proton gradient

Question 9

oxidation of glucose

slide 16

Answer 9

1. glycolysis
2. pyruvate oxidation
3. krebs cycle
4. electron transport chain and chemiosmosis
   (oxidation proceeds in stages)

Question 10

glycolysis

slide 18

Answer 10

• converts 1 glucose (6 carbons) to 2 pyruvate (3 carbons)
• 10 step biochemical pathway
• occurs in cytoplasm
• 2 ATP made my substrate-level phosphorylation
• 2 NADH produced by the reduction of NAD⁺

Question 12

all organisms use cellular respiration to extract energy from organic molecules

slide 3