Biology: Ch. 3 Cellular Respiration

Question 1

Cellular respiration equation

Answer 1

C6H12O6 + 6O2 –> 6 CO2 + 6 H2O + energy

Question 2

Aerobic respiration

Answer 2

Cellular respiration in the presence of oxygen

Question 3

Three components of cellular respiration

Answer 3

Glycolysis, Krebs Cycle, Oxidative Phosphorylation

Question 4

Glycolysis

Answer 4

• Decomposition of Glucose to pyruvate
• 2 ATP added
• 2 NADH produced
• 4 ATP produced (2 net ATP)
• 2 pyruvate formed

Question 5

The Krebs Cycle/ Citric Acid Cycle/ Tricarboxylic Acid (TCA) Cycle

Answer 5

• Pyruvate is converted to Acetyl-CoA

- 3 NADH, 1 FADH2, 1 ATP, 2 CO2

Question 6

Oxidative Phosphorylation

Answer 6

• Process of extracting ATP from NADH and FADH2 as their electrons pass along an electron transport chain
• Pass along carrier proteins such as cytochromes, which contain iron
• NADH: 3 ATP
• FADH2: 2 ATP
• Final electron acceptor: Oxygen ; Forms water

Question 7

How many ATP from glycolysis?

Answer 7

• 2 NADH, 2 ATP, 2 pyruvate
• 4 (b/c transport across mito. membrane) + 2 = 6 ATP
• Ahmad: 7 ATP

Question 8

How many ATP from conversion of pyruvate to acetyl-CoA?

Answer 8

• 1 NADH for each pyruvate = 2 NADH
• 6 ATP
• Ahmad: 5 ATP

Question 9

How many ATP from Krebs cycle?

Answer 9

• 2 ATP, 6 NADH, 2 FADH2
• 24 ATP
• Ahmad: 20 ATP

Question 10

Components of mitochondria

Answer 10

• Outermembrane: double layer of phospholipids
• Intermembrane space: B/w inner and outer membrane; H+ ions accumulate here
• Inner membrane: double phospholipid bilayer with convulsions called cristae; oxidative phosphorylation occurs here
• Matrix: Krebs cycle and conversion of pyruvate to acetyl-CoA occur here

Question 11

Chemiosmosis

Answer 11

Mechanism of ATP generation when energy is stored in the form of a proton concentration gradient

Question 12

Process of chemiosmosis

Answer 12

• NADH and FADH2 produced in matrix during Krebs Cycle
• Electrons removed from NADH and FADH2 as they pass along the protein complexes
• Protons transported from matrix to intermembrane compartment
• pH and electrical gradient are created
• ATP synthase generates ATP

Question 13

Two types of phosphorylation

Answer 13

1. Substrate level phosphorylation: phosphate group and associated energy transferred from substrate molecule to ADP
2. Oxidative Phosphorylation: Phosphate group added to ADP with the energy coming from the H+ gradient

Question 14

Anaerobic respiration

Answer 14

-When no oxygen is present, NAD+ is replenished by alcohol or lactic acid fermentation

Question 15

Alcohol fermentation

Answer 15

• Pyruvate to acetaldehyde: Produces 1 CO2

- Acetaldehyde to ethanol: Produces 1 NAD+

Question 16

Lactic Acid Fermentation

Answer 16

• Pyruvate to lactate: Produces 1 NAD+

- Humans & mammals: lactate transported to liver; can be converted back to glucose when surplus ATP is available