Biology Chapter on Energy Processes

Questions and Answers

What is the net gain of ATP produced during glycolysis for each glucose molecule?

4 ATP

2 ATP (correct)

0 ATP

6 ATP

Which of the following processes is dependent on the presence of oxygen?

Glycolysis

Citric Acid cycle

Fermentation

Electron transport chain (correct)

What happens to glucose during cellular respiration?

It undergoes fermentation

It is reduced

It is oxidized (correct)

It remains unchanged

What is produced during the transition reaction in mitochondria?

NADH and Acetyl CoA Signup and view all the answers

Which statement best describes the efficiency of cellular respiration?

It captures only about 40% of energy as ATP. Signup and view all the answers

What is the final product of the electron transport chain?

Water Signup and view all the answers

Which coenzymes are involved in carrying high-energy electrons during cellular respiration?

NAD+ and FAD+ Signup and view all the answers

How many ATP molecules are produced in the citric acid cycle per glucose molecule?

2 ATP Signup and view all the answers

Which process occurs in the cytoplasm of the cell?

Glycolysis Signup and view all the answers

What is the role of oxygen in respiration?

It is the final electron acceptor. Signup and view all the answers

Study Notes

Benefits of Exercise

Improves oxygen intake and delivery to muscles.
Increases lung capacity and red blood cell production.
Enhances blood supply to the brain and strengthens the heart.

Autotrophs and Heterotrophs

Autotrophs produce their own food.
Heterotrophs obtain energy by consuming other organisms.

Energy Flow in Ecosystems

Energy enters ecosystems through sunlight and exits as heat.

Photosynthesis and Cellular Respiration Relationship

Photosynthesis produces oxygen and organic molecules utilized in cellular respiration.

Cellular Respiration Overview

All living cells convert chemical energy in organic molecules into ATP for powering cellular work.
Breakdown of organic molecules is exergonic.

Fermentation and Respiration Types

Fermentation partially degrades sugars without the use of oxygen.
Aerobic respiration utilizes organic molecules and oxygen to produce ATP.
Anaerobic respiration resembles aerobic but utilizes compounds other than oxygen.

Cellular Respiration Chemical Reaction

Glucose and oxygen convert to carbon dioxide, water, ATP, and heat.
Equation: $C_6H_{12}O_6 + 6O_2 → 6CO_2 + 6H_2O + 38ATP + heat$.
Glucose, fats, and proteins oxidized to produce carbon dioxide.
Oxygen is reduced to form water.

Efficiency and Energy Loss

Cellular respiration is 40% efficient at converting energy into ATP; remaining energy is lost as heat.

Electron Carriers

High-energy electrons from glucose are accepted by NAD+ and FAD+.
These co-enzymes transport electrons to the electron transport system to produce water.

Oxidation-Reduction (Redox) Reactions

Involves transfer of electrons between reactants, impacting electron sharing in covalent bonds.
Oxidation is electron loss; reduction is electron gain (remember "OIL RIG").
Reducing agents donate electrons; oxidizing agents accept them.

Steps of Cellular Respiration

Glycolysis: Occurs in cytoplasm, splits glucose into two pyruvate molecules, requiring 2 ATP, yielding 4 ATP and generating NADH and FADH2, resulting in a net gain of 2 ATP.
Transition Reaction: Takes place in the mitochondria, converts pyruvate into acetyl CoA, producing 2 carbon dioxide molecules.
Citric Acid Cycle (Krebs Cycle): Cyclic series in the mitochondria's matrix, processes each acetyl CoA into 2 carbon dioxide and 2 ATP; turns twice per glucose molecule produces due to two acetyl CoA from one glucose.
Electron Transport Chain: Occurs in cristae of mitochondria, requires oxygen, processes high-energy electrons from NADH and FADH2, generating 90% of ATP (32-34 ATP), with oxygen as the final electron acceptor forming water.