Class 11 Biology Chapter 8 Cell – The Unit of Life – Revision Notes

Quick revision notes for Class 11 Biology Chapter 8 (Cell: The Unit of Life). These Class 11 Biology Chapter 8 notes are ideal for quick revision just before exams.

Cell Theory

• Schleiden & Schwann + Virchow: cells are the basic unit of life; all cells from pre-existing cells.

Prokaryotic vs Eukaryotic

• Prokaryotic: no membrane-bound nucleus/organelles, 70S ribosomes.
• Eukaryotic: membrane-bound nucleus/organelles, 80S ribosomes (70S in mitochondria/chloroplast).

Key Organelles

• Nucleus (genetic control), ER (rough/smooth), Golgi (packaging), Mitochondria (ATP), Chloroplast (photosynthesis), Lysosome (digestion), Vacuole (storage/turgor).

Membrane and Wall

• Plasma membrane: fluid mosaic model (Singer & Nicolson).
• Cell wall: cellulose (plants), chitin (fungi).

One-Line Summary

The cell is the fundamental structural and functional unit of life, with prokaryotic cells lacking and eukaryotic cells possessing a true nucleus and membrane-bound organelles that perform specialized functions.

Written by Satish

NCERTBooks.org is an independent educational resource run by a small team focused on making official NCERT textbooks easy to find, read, and download for students, parents, and teachers across India. We are not affiliated with NCERT or the Ministry of Education -- we organise publicly available NCERT content by class and subject, verify links against official sources, and build tools (like our in-browser reader) that make studying more convenient. Every guide we publish is written and reviewed by our team based on the actual NCERT curriculum and syllabus.