Cellular Respiration: Maximizing ATP Yields

Question 1

What is cellular respiration?

Answer 1

oxidation-driven flow of electrons from reduced coenzymes to an electron acceptor, usually accompanied by the generation of ATP

Question 2

What is aerobic respiration?

Answer 2

process where the terminal electron receptor is oxygen, the reduced form of this terminal electron acceptor is water

Question 3

what is anaerobic respiration?

Answer 3

respiratory process that involves electron acceptors such as sulfur, protons and ferric ions that require no molecular oxygen

Question 4

Where does cellular respiration, aerobic respiration and anaerobic resipiration occur?

Answer 4

Mitochondria

Question 5

compared to fermentation why does aerobic respiration yield more energy?

Answer 5

with oxygen as the terminal electron acceptor, pyruvate can be oxidized completely as CO2 instead of being used to accet electrons from NADH.

Generates 38 ATP molecules per 1 glucose molecule

Question 6

what are the five stages of aerobic respiration?

Answer 6

1. the glycolytic pathway
2. pyruvate is oxidized to generate acetyl CoA
3. acetyl CoA enters the TCA cycls, where it is completely oxidized to CO2
4. electron transport, the transfer of electrons from reduced coenzymes to oxygen coupled to active transport of protons across a membrane
5. the electrochemical proton gradient formed in #4 is used to drive ATP synthesis (oxidative phsophrylation)

Question 7

Mitochondria structure:

describe the outer membrane

Answer 7

not a significant permeability barrier for ions and small molecues because it contains porins that permit the passage of solutes

Question 8

Mitochondria structure:

describe the intermembrane structure

Answer 8

between the inner and outer membranes is continuous with the cytosol with respect to small solutes

Question 9

Mitochondria structure:

describe the inner membrane

Answer 9

permeability barrier to most solutes, partitions the mitochondria into two portions (intermembrane space & matrix) also has cristae, which are infoldings that greatly increase the surface area

Question 10

Mitochondria structure:

Describe the matrix

Answer 10

cotains enzymes involved in mitochondrial function as well as DNA molecules and ribosomes