Biology
📌 Movement into & out of the cells
1⃣ Diffusion 🌬
📌 Definition: The movement of molecules from high concentration to low concentration until it reaches equilibrium.
✅ Examples:
Oxygen diffusing into red blood cells 🩸
Glucose diffusing from the blood into body cells 🍬
Carbon dioxide diffusing out of cells during respiration
⚡ Factors Affecting Diffusion:
🔥 Temperature → Higher temp = Faster diffusion
📏 Surface Area → Larger SA = Faster diffusion (e.g., alveoli in lungs 
)
📉 Concentration Gradient → Steeper gradient = Faster diffusion
2⃣ Osmosis 💦
📌 Definition: The movement of water molecules from high water potential to low water potential until it reaches equilibrium
✅ Examples:
🌱 Plant cells in water:
Hypotonic Solution (Dilute water) → Water enters, cell becomes turgid (firm) 🌿
Hypertonic Solution (Concentrated solution) → Water leaves, cell becomes flaccid (shrunken) 🥀
Plasmolysis → Extreme water loss where the membrane pulls away from the cell wall 🏜
🔬 Osmosis Experiment:
🥔 Potato Experiment:
Potato in distilled water → Gains mass (water moves in)
Potato in saltwater → Loses mass (water moves out)
3⃣ Active Transport 🚛
📌 Definition: The movement of molecules against the concentration gradient (low to high) using ATP energy ⚡.
✅ Example:
🌱 Root hair cells absorbing minerals from the soil, even when the concentration is lower outside the cell.
💪 Small intestine absorbing glucose into the blood.