Cell Organelles and Their Functions
🧰 What Are Cell Organelles?
Cell organelles are specialized structures within the cytoplasm that perform specific functions necessary for the survival of the cell.
🧠 Think of them as mini-organs of the cell — each with its own job!
🧪 Major Cell Organelles and Their Functions
🔋 1. Mitochondria – Powerhouse of the Cell
- Produces energy by breaking down food (glucose)
- Site of cellular respiration
- Present in large numbers in active cells (e.g., muscle cells)
🧵 2. Endoplasmic Reticulum (ER) – Transport System
- A network of membrane-bound tubes
- Rough ER: Has ribosomes → helps in protein synthesis
- Smooth ER: No ribosomes → helps in fat (lipid) synthesis and detoxification
📦 3. Golgi Apparatus (Golgi Body) – Packaging Unit
- Modifies, packages, and transports proteins and lipids
- Looks like a stack of pancakes (flattened sacs)
🧼 4. Lysosomes – Suicide Bags
- Contain digestive enzymes
- Break down waste, old organelles, or harmful substances
- Can burst and digest the cell itself (self-destruction)
💧 5. Vacuoles – Storage Sacs
- Store water, food, and waste materials
- Large in plant cells, small in animal cells
- Helps maintain shape (turgidity) in plant cells
🌱 6. Plastids – Only in Plant Cells
- Chloroplasts – Contain green pigment chlorophyll, site of photosynthesis
- Chromoplasts – Colored plastids (red, yellow)
- Leucoplasts – Colorless, store food (like starch)
⚙️ 7. Ribosomes – Protein Factories
- Small dot-like structures
- Site of protein synthesis
- Found floating in cytoplasm or attached to ER
🧭 8. Centrosome/Centrioles – Only in Animal Cells
- Help in cell division
- Form spindle fibers that pull chromosomes apart
🧱 9. Cytoskeleton
- Protein filaments that give shape and support to the cell
- Involved in movement within the cell
📌 Recap: Organelles and Functions Table
| Organelle | Function | Special Note |
|---|---|---|
| Mitochondria | Energy production | Powerhouse of the cell |
| ER (Smooth & Rough) | Transport, protein & lipid synthesis | Rough ER has ribosomes |
| Golgi Apparatus | Packaging and secretion | Flattened sacs |
| Lysosomes | Digestion of waste | Suicide bags |
| Vacuoles | Storage | Large in plants |
| Plastids | Photosynthesis, pigment & food storage | Only in plant cells |
| Ribosomes | Protein synthesis | Non-membranous |
| Centrosome | Cell division | Only in animal cells |
🧠 Think & Explore
- 👉 Why are mitochondria called the powerhouse of the cell?
- 👉 Why don’t animal cells have chloroplasts?