Biology Chapter on Energy Processes

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.

Description

Explore the essential concepts of energy processes in biology, including the differences between autotrophs and heterotrophs, as well as the roles of photosynthesis and cellular respiration. This quiz covers how energy flows through ecosystems and the types of respiration. Test your knowledge on these foundational topics in biological science.