Respiration in Organisms
Explore the fascinating process of respiration in organisms. Learn about human breathing, gas exchange, cellular respiration, and how to demonstrate that we breathe out carbon dioxide.
Help & Instructions
â–¼- Respiration Process: Arrange the steps of respiration in correct order
- CO2 Experiment: Set up the experiment to show we breathe out carbon dioxide
- Use the hint button if you need help with any section
- Try different activities to learn about various aspects of respiration
- Understand the process of respiration in the human body
- Learn how to demonstrate that we breathe out carbon dioxide
- Differentiate between aerobic and anaerobic respiration
- Identify the organs involved in the respiratory system
Respiration Process: Arrange the Steps
Drag and drop the steps of respiration in the correct order.
CO2 Experiment: Set Up the Demonstration
Arrange the apparatus to show that we breathe out carbon dioxide.
Respiration is the process by which organisms exchange gases with their environment. In humans, breathing involves inhaling oxygen-rich air and exhaling carbon dioxide-rich air. Cellular respiration then uses oxygen to break down glucose and release energy in cells.
Respiration in Organisms Concepts
The respiratory system includes these key organs:
- Nose and Mouth: Entry points for air
- Trachea (Windpipe): Tube that carries air to lungs
- Bronchi: Tubes that branch into each lung
- Bronchioles: Smaller branches inside lungs
- Alveoli: Tiny air sacs where gas exchange occurs
- Diaphragm: Muscle that helps in breathing
Respiration involves these key steps:
- Breathing In (Inhalation): Diaphragm contracts, rib cage expands, air enters lungs
- Gas Exchange in Alveoli: Oxygen diffuses into blood, CO2 diffuses out
- Transport: Blood carries oxygen to cells and CO2 back to lungs
- Cellular Respiration: Cells use oxygen to break down glucose and produce energy
- Breathing Out (Exhalation): Diaphragm relaxes, rib cage contracts, air leaves lungs
We can prove we breathe out CO2 using limewater test:
- Limewater (calcium hydroxide solution) turns milky when CO2 is bubbled through it
- When we exhale into limewater, it turns milky, proving CO2 is present
- This is a simple chemical test: CO2 + Ca(OH)2 → CaCO3 (milky) + H2O
Organisms use different types of respiration:
- Aerobic Respiration:
- Requires oxygen
- Produces more energy (36-38 ATP molecules per glucose)
- End products: CO2 and H2O
- Occurs in mitochondria
- Equation: C6H12O6 + 6O2 → 6CO2 + 6H2O + Energy
- Anaerobic Respiration:
- Does not require oxygen
- Produces less energy (2 ATP molecules per glucose)
- End products: Lactic acid (in muscles) or ethanol + CO2 (in yeast)
- Occurs in cytoplasm
- Equation (in muscles): C6H12O6 → 2C3H6O3 (lactic acid) + Energy
Different organisms have different respiratory structures:
- Humans and Mammals: Lungs
- Birds: Lungs with air sacs for efficient oxygen extraction
- Fish: Gills that extract oxygen from water
- Insects: Tracheal tubes that deliver air directly to cells
- Earthworms: Skin (cutaneous respiration)
- Plants: Stomata in leaves for gas exchange
