Chapter 7: Cellular Respiration and Fermentation

Question 1

What are the three key pathways to cellular respiration?

Answer 1

Glycolysis, The citric acid cycle (Krebs cycle), and oxidative phosphorylation at the ETC

Question 2

What are catabolic pathways

Answer 2

pathways that break down organic molecules, releasing stored energy

Question 3

How do organic molecules possess potential energy?

Answer 3

As a result of the arrangment of electrons in the bonds betweeen their atoms

Question 4

What is fermentation

Answer 4

The partial breakdown of sugars without O2 (anaerobic)

Question 5

What is aerobic respiration?

Answer 5

The most efficient catabolic pathway. This occurs in the presence of O2 which makes this an aerobic process.

Question 6

What is the chemical equation for cellular respiration?

Answer 6

C6H12O6 + 6O2 –> 6 CO2 + 6H20 + NRG

Question 7

Is cellular resperiation exergonic or endergonic?

Answer 7

exergonic

Question 8

How is ATP synthesized in cellular respiration (summarized)

Answer 8

When cells break down glucose, the realocation of electron releases energy stored in organic molecules, and this energy is used to synthesize ATP

Question 9

What is oxidation?

Answer 9

the loss of electrons

Question 10

What is reduction?

Answer 10

the addition of electrons

Question 11

What is the reducing agent?

Answer 11

the electron donor

Question 12

What is the oxidizing agent?

Answer 12

the electron acceptor

Question 13

How do electrons move throughout compounds?

Answer 13

AN electron loses potential energy when it shifts from a less electronegative atom toward a more electronegative atom

Question 14

Is glucose oxidized or reduced?

Answer 14

oxidized

Question 15

Is O2 oxidized or reduced?

Answer 15

reduced

Question 16

Why are organic molecules with many hydrogen atoms great sources for energy?

Answer 16

These type of molecules are high in energy (hydrocarbons) because they are a soruce of “hilltop” (high energy) electrong with the potential to fall closer to O2

Question 17

If electrons and H+ ions were transferred directly to oxygen what would occur?

Answer 17

This reaction would result in an uncontrolled release of energy. This release of energy would cause the cells of living organisms to immediately die.

Question 18

Which coenzyme functions as an oxidizing agent?

Answer 18

NAD+

Question 19

Is NAD+ reduced or oxidized and how?

Answer 19

NAD+ is reduced and becomes NADH with the addition 2 electrons (2e-) and 1 Proton (H+)

Question 20

What is the function of dehydrogenases?

Answer 20

they remove a pair of hydrogen atoms (2 electrons and 2 protons) from the substrate, thereby oxidizing it.

Question 21

How many electrons and protons does NAD+ deliver to the ETC?

Answer 21

NAD+

Question 22

Which oxidizing agent delivers more energy: NAD+ or FAD

Answer 22

NAD+