NEET 2025 – Cell: The Unit of Life | NCERT-Based Notes + Diagrams

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Post Content:

Introduction:
"Cell: The Unit of Life" is a conceptual and factual chapter. NEET 2025 can include diagram-based MCQs and questions from cell organelles and types of cells. Focus on NCERT keywords and functions.

1. Discovery of Cell

Discovered by Robert Hooke in 1665 (cork cell)

Cell Theory by Schleiden & Schwann

Rudolf Virchow: "Omnis cellula-e-cellula" – cells arise from pre-existing cells

2. Prokaryotic vs Eukaryotic Cells

Feature Prokaryote (Bacteria) Eukaryote (Plants/Animals)

Nucleus Absent Present
Organelles No membrane-bound Membrane-bound
Ribosome Type 70S 80S
Cell Wall Peptidoglycan Cellulose (plants)


3. Cell Organelles

Nucleus: Double membrane, contains nucleolus and chromatin

Mitochondria: Powerhouse, double membrane, has its own DNA

Plastids:

Chloroplast: Green, photosynthesis, has DNA


Endoplasmic Reticulum (ER):

Rough ER: Protein synthesis

Smooth ER: Lipid synthesis


Golgi Apparatus: Modifies & packages proteins

Lysosomes: Contain hydrolytic enzymes (suicide bags)

Ribosomes: 70S (prokaryotes), 80S (eukaryotes)

Centriole: In animal cells, for spindle formation

4. Differences: Plant vs Animal Cell

Feature Plant Cell Animal Cell

Cell Wall Present (cellulose) Absent
Plastids Present Absent
Vacuole Large central Small, scattered
Centriole Absent Present

5. NCERT Diagram Practice

Prokaryotic cell (E. coli)

Plant and Animal cell labeled diagrams

Mitochondria and Nucleus internal structure

Quick Mnemonic (for Cell Organelles):

"Never Make Pink Elephants Glide Like Rabbits Carefully"
(Nucleus, Mitochondria, Plastids, ER, Golgi, Lysosomes, Ribosomes, Centrioles)

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