Respiration

What is Respiration?

✅ Definition:

Respiration is the process by which living organisms release energy from glucose (sugar) by breaking it down — usually in the presence of oxygen.

📌 It is how cells get energy to carry out life functions like growth, repair, movement, etc.

⚡ Why is respiration important?

• Provides energy (ATP) for all cellular activities

• Keeps cells and organs functioning

• Helps in muscle movement, nerve signals, and body temperature regulation

🧬 Types of Respiration:

🧪 Word Equation (for Aerobic Respiration):

Glucose+Oxygen→Carbon dioxide+Water+Energy (ATP)\text{Glucose} + \text{Oxygen} \rightarrow \text{Carbon dioxide} + \text{Water} + \text{Energy (ATP)}

In words:

C6H12O6+6O2→6CO2+6H2O+energy (ATP)C_6H_{12}O_6 + 6O_2 \rightarrow 6CO_2 + 6H_2O + \text{energy (ATP)}

• Glucose (sugar): comes from food (or photosynthesis in plants)

• Oxygen: from breathing (animals) or diffusion (plants)

• ATP: Adenosine Triphosphate — the energy molecule of the cell

🧬 Where does respiration happen?

• In every cell of the body

• Inside special cell parts called mitochondria — often called the “powerhouses” of the cell

💨 Anaerobic Respiration:

When oxygen is not available, cells can still make energy using anaerobic respiration, but:

• Less energy is produced

• Byproducts like lactic acid (in animals) or ethanol + CO₂ (in yeast) are created

• Causes muscle fatigue during intense exercise

🧠 Simple Comparison: Respiration vs. Photosynthesis

🧠 Fun Facts:

• The average human cell contains about 1000–2000 mitochondria

• You produce around 32 molecules of ATP per glucose molecule during aerobic respiration

• Lactic acid build-up from anaerobic respiration causes muscle soreness

• Respiration happens 24/7 — even when you're asleep!

📌 Summary Table: