Chapter 6: How Cells Harvest Chemical Energy

Question 1

Multicellular Respiration

Answer 1

Removes the CO2 Produced as a Waste Product​.

Bodily Respiration, aka “breathing,” refers to the metabolic exchange of the gases O2 & CO2.​

Question 2

Cellular Respiration

Answer 2

is an exergonic (energy-releasing) process that transfers energy from glucose to form A T P and​

captures about 34% of the available energy originally stored in glucose with the rest of the energy lost as heat.​

Question 3

How Cells Capture Energy

Answer 3

Cells extract energy from fuel molecules in a process with electron transfer via chemical reactions.​

Electrons removed from food molecules via oxidation reactions are transferred to N A D+ via reduction reactions. ​

N A D H passes electrons to an electron transport chain. ​

As electrons pass from carrier molecule to carrier molecule and finally to O2 in a series of redox reactions, energy is released​

​

Question 4

Steps of Aerobic Respiration

Answer 4

1. Glycolysis: Glucose —> Pyruvate
2. Pyruvate oxidation —> citric acid cycle (CO2 byproduct)
3. Oxidative phosphorylation (O2 and H2O) —> ATP

Question 5

Glycolysis (Stage 1)

Answer 5

occurs in the cytosol (cytoplasm),​

begins cellular respiration, and​

breaks down glucose into two molecules of a three-carbon compound called pyruvate.​

Question 6

Pyruvate Oxidation (Stage 2)

Answer 6

take place in mitochondria,​

complete breakdown of glucose to carbon dioxide​

supply the third stage of respiration with electrons.​

Question 7

Phosphorylation w/ Electron Transport (Stage 3)

Answer 7

NADH & FADH2 shuttle electrons to electron transport chains embedded in the inner mitochondrial membrane.​

Most ATP produced by cell respiration is generated by oxidative phosphorylation.​

Chemiosmosis: movement of H+ ions down their electrochemical gradient across the selectively permeable inner mitochondrial membrane.​

Transported electrons & relocated H+ ions are finally passed to oxygen, which becomes reduced to H2O.​

Question 8

Glycolysis

Answer 8

-Occurs in the cytoplasm

Question 9

Chemiosmosis

Answer 9

the H+ gradient drives H+ back through the enzyme complex ATP synthase in the inner membrane, synthesizing ATP​

Question 10

ATP Production

Answer 10

-mostly occurs by oxidative phosphorylation

Question 11

Anaerobic Cell Respiration

Answer 11

-Glycolysis Breaks Each Glucose Molecule Down Into 2 Pyruvate Molecules

-that then Undergo Lactic Acid Fermentation or Alcohol Fermentation ​

Question 12

Fermentation

Answer 12

-enables cells to produce ATP w/o o2

-Under anaerobic conditions, muscle cells, yeasts, and certain bacterias produce ATP by glycolysis

-NAD+ is recycled from NADH as pyruvate is reduced to lactate (lactic acid fermentation)

Question 13

Aerobic Respiration Formula

Answer 13

C6H12O6 (glucose) + 6 O2——-> 6 CO2 + 6 H2O + ATP + Heat

Question 14

Fuel Molecules

Answer 14

-Fats, carbs, and proteins

Question 15

Lactic vs. Ethanol Fermentation

Answer 15

Lactic: muscles

Eth. : Yeasts