Cellular Respiration

Study Notes

Cellular Respiration

Definition: The process by which cells generate energy from glucose, releasing carbon dioxide and water as byproducts
Types:
- Aerobic Respiration: Occurs in the presence of oxygen, produces ATP and water
- Anaerobic Respiration: Occurs in the absence of oxygen, produces lactic acid or ethanol
Stages:
1. Glycolysis: Breakdown of glucose into pyruvate
2. Citric Acid Cycle (Krebs Cycle): Conversion of pyruvate into ATP, NADH, and FADH2
3. Electron Transport Chain: Generation of ATP from NADH and FADH2

Photosynthesis

Definition: The process by which plants, algae, and some bacteria convert light energy into chemical energy
Equation: 6 CO2 + 6 H2O + light energy → C6H12O6 (glucose) + 6 O2
Importance: Produces oxygen and organic compounds for the food chain
Light-Dependent Reactions: Convert light energy into ATP and NADPH
Light-Independent Reactions (Calvin Cycle): Fix CO2 into glucose using ATP and NADPH

Exchange of Gases

Definition: The process of exchanging oxygen and carbon dioxide between the environment and an organism
Mechanisms:
- Diffusion: Movement of gases from high concentration to low concentration
- Active Transport: Movement of gases against concentration gradient using energy
Sites of Gas Exchange:
- Lungs (human)
- Gills (fish)
- Skin (amphibians)
- Leaves (plants)

Human Respiratory System

Components:
- Nose and Mouth: Air enters and is filtered
- Trachea: Air passes through and divides into bronchi
- Bronchi: Air passes through and divides into bronchioles
- Alveoli: Gas exchange occurs between air and blood
Functions:
- Inhaling oxygen
- Exhaling carbon dioxide
- Regulating pH levels

Breathing Mechanism

Definition: The process of inhaling and exhaling air
Steps:
1. Inspiration: Diaphragm contracts, chest cavity expands, air enters lungs
2. Expiration: Diaphragm relaxes, chest cavity decreases, air exits lungs
Muscles involved:
- Diaphragm: Primary muscle of inspiration
- Intercostal muscles: Assist in inspiration and expiration
- Accessory muscles: Used during forced breathing (e.g., neck, back, and abdominal muscles)

Cellular Respiration

Cellular respiration generates energy from glucose, producing CO2 and H2O as byproducts
There are two types of cellular respiration: aerobic (with oxygen) and anaerobic (without oxygen)
Aerobic respiration produces ATP and water, while anaerobic respiration produces lactic acid or ethanol
The three stages of cellular respiration are glycolysis, citric acid cycle, and electron transport chain
Glycolysis breaks down glucose into pyruvate
Citric acid cycle converts pyruvate into ATP, NADH, and FADH2
Electron transport chain generates ATP from NADH and FADH2

Photosynthesis

Photosynthesis converts light energy into chemical energy in plants, algae, and some bacteria
The equation for photosynthesis is 6 CO2 + 6 H2O + light energy → C6H12O6 (glucose) + 6 O2
Photosynthesis produces oxygen and organic compounds for the food chain
Light-dependent reactions convert light energy into ATP and NADPH
Light-independent reactions (Calvin cycle) fix CO2 into glucose using ATP and NADPH

Exchange of Gases

Exchange of gases involves the exchange of oxygen and carbon dioxide between the environment and an organism
Gases move through diffusion (from high to low concentration) and active transport (against concentration gradient using energy)
Sites of gas exchange include lungs (humans), gills (fish), skin (amphibians), and leaves (plants)

Human Respiratory System

The human respiratory system consists of nose and mouth (air enters and is filtered), trachea (air passes through and divides into bronchi), bronchi (air passes through and divides into bronchioles), and alveoli (gas exchange occurs between air and blood)
The functions of the human respiratory system include inhaling oxygen, exhaling carbon dioxide, and regulating pH levels

Breathing Mechanism

Breathing mechanism involves the process of inhaling and exhaling air
Inspiration occurs when the diaphragm contracts, chest cavity expands, and air enters lungs
Expiration occurs when the diaphragm relaxes, chest cavity decreases, and air exits lungs
Muscles involved in breathing include diaphragm (primary muscle of inspiration), intercostal muscles (assist in inspiration and expiration), and accessory muscles (used during forced breathing)

Description

Test your knowledge on the process of cellular respiration, including its definition, types, and stages. From glycolysis to the electron transport chain, see how well you understand how cells generate energy.