Cell Organelles

• Cell membrane — selective barrier; cell wall (plants) — rigidity and protection.
• Nucleus — control centre; chromosomes, DNA.
• Cytoplasm — fluid matrix; mitochondria (powerhouse), plastids (chloroplast in plants), vacuoles, ER, Golgi, ribosomes, lysosomes.

1. Nucleus — nuclear membrane, nucleolus, chromatin/chromosomes; directs cell activities.
2. Mitochondria — aerobic respiration; ATP energy (double membrane).
3. Chloroplast — photosynthesis in plants (chlorophyll); double membrane.
4. Endoplasmic reticulum — rough (ribosomes) → protein; smooth → lipids.
5. Golgi apparatus — packaging, modification, secretion.
6. Lysosomes — digestive enzymes; 'suicide bags'.
7. Vacuole — large in plant cells (turgor); storage.
8. NCERT Ch. 5 — diagram of plant and animal cell with labels.

Matching organelle to function

Chloroplast → photosynthesis (light energy to food)
Mitochondria → release energy from glucose (respiration)
Ribosome → protein synthesis
Lysosome → break down worn organelles / foreign material
Nucleus → stores genetic information; controls division
Cell membrane → regulates entry/exit of substances
Conclusion: structure linked to function in each organelle.

• Saying mitochondria photosynthesise (chloroplast does).
• Misconception: animal cells have chloroplasts (only plant/algae cells).
• Confusing cell wall and cell membrane.
• Thinking all cells have large vacuole (prominent in plant cells).
• Forgetting ribosomes are site of protein synthesis.

• Name the 'powerhouse' of the cell.
• Which organelle is found only in plant cells?
• Function of nucleus and lysosomes.
• What is the role of cell membrane?

Open the Practice tab for graded questions on Cell Organelles.