Cellular Respiration

Question 1

Catabolism

Answer 1

Catabolic reactions are exergonic, energy releasing reactions. These are used to generate ATP in cellular respiration.

Question 2

Substrate-level phosphorylation

Answer 2

Is used to make small amounts of ATP throughout cellular respiration. The phosphate added to ADP is coming from the substrate rather than inorganic phosphate as in oxidative phosphorylation.

Question 3

Glycolysis

Reactants? Products?

Answer 3

Input: Glucose, 2 ATP, 2NAD+,
Output: 4 ATP, 2 Pyruvate, 2 H2O, 2 NADH
- The first step in cellular respiration which occurs in the cytoplasm and is anaerobic.

Question 4

Chemiosmosis

Answer 4

The last step in cellular respiration in which ATP synthase is driven by the proton gradient in the intracellular space, binding inorganic phosphates to ADP.

Question 5

Mitochondria

What is the result of defects in mitochondrial function?

Answer 5

Site of cellular respiration in all eukaryotic cells

Mitochondrial defects are associated with degenrative diseases, cancer, and aging. Symptoms include muscle weakness, neurodegeneration, and metabolic dysfunction.

Question 6

What components are reduced and oxidized in the cellular respiration equation?

Answer 6

C6H12O6 + 6O2 -> 6CO2 + 6H2O
- Glucose is oxidized to CO2
- Oxygen is reduced to H2O
- Equation has a negative free energy and is therefore exothermic. Energy is released.

Electrons release potential energy when moving from less electronegative atoms to more electronegative ones.

Question 7

NADH

Answer 7

The electron carrier in cellular respiration. This carries electrons to the transport chain.

Dehydrogenase enzymes take 2 H atoms and 2 electrons from glucose. 1 H+ gets released and the rest goes to form NADH.

Question 8

Oxidation of Pyruvate

Reactants? Products?

Answer 8

Input: 1 Pyruvate
Output: CO2 + NADH + Acetyl CoA
- THERE ARE TWO PYRUVATES FROM GLYCOLYSIS

Occurs in the mitochondrial matrix. Pyruvate enters by active transport.

Question 9

Citric Acid Cycle

Reactants? Products?

Also called Krebs Cycle or Tricarboxylic Acid Cycle

Answer 9

Input: Acetyl CoA
Output: 2CO2 + 3NADH + 1FADH2 + 1ATP
- THERE ARE TWO ACETYL COA FROM OXIDATION OF PYRUVATE

Occurs in the mitochondrial matrix.

ATP isnt always made because sometimes GTP is made instead.

Question 10

Oxidative Phosphorylation

WHAT IS THE ETC???

Answer 10

• Composed of the ETC and Chemiosmosis
• In the ETC, FADH2 and NADH donate their electrons, and the transport of electrons through the ETC powers proton pumps that devise a proton gradient in which the intermembrane space passively diffuses protons through ATP synthase back into the mitochondrial matrix
• Oxygen is the final acceptor, producing water at the end of the process.

Question 11

How much ATP is made per glucose in Cellular Respiration?

Answer 11

30-32 ATP

GTP can be made instead of ATP for each Acetyl CoA during the Citric Acid cycle