Chapter 2 of 19
Revision Notes
Biological Classification — Revision Notes
ICSE · Class 11 · Biology
Biological Classification revision notes for ICSE Class 11 Biology: 4 topics in quick points. Part of the ICSE Class 11 Biology syllabus.
64 questions57 flashcards5 concepts
Interactive on Super Tutor
Studying Biological Classification? Get the full interactive chapter.
Quizzes, flashcards, AI doubt-solver and a step-by-step study plan — built for revision notes and more.
Free trial, no card needed.

Super Tutor
Learn better with visuals Super Tutor pairs illustrations like this with notes and quizzes for Biological Classification.
Key Topics to Revise
1
1. History of Classification and Major Systems
- Aristotle was the earliest to attempt a more scientific basis of classification. He used simple morphological characters to classify plants into trees, shrubs and herbs, and animals into those with re
- Linnaeus proposed the Two-Kingdom system with Plantae and Animalia based on form and constitution.
- Ernst Haeckel added a third kingdom, Protista, in 1866 to include bacteria, algae, fungi and protozoa with cellular grade organisation.
2
2. Kingdom Monera
- Monera includes prokaryotic, single-celled organisms.
- A typical moneran has a naked circular DNA molecule that acts as the chromosome.
- Membrane-bound organelles and a true nucleus are absent.
3
3. Classification and Features of Bacteria
- On the basis of shape, bacteria are bacillus, coccus, spirillum and vibrio.
- An average bacillus is about 1.5 micrometres long and 0.5 micrometres in diameter.
- Cocci measure 0.5 to 1.25 micrometres in diameter and are generally non-motile.
4
4. Kingdom Protista
- Protista includes diverse unicellular eukaryotic organisms.
- Members of Protista are primarily aquatic.
- Protists evolved about 1.6 billion years ago.
Get complete notes with diagrams and examples
Full NotesKey Concepts
Living organisms are extremely diverseAristotle used simple morphological charactersErnst Haeckel added Protista in 1866RMonera includes prokaryotic
Frequently Asked Questions
What are the important topics in Biological Classification for ICSE Class 11 Biology?
Key topics in Biological Classification include History of Classification and Major Systems, Kingdom Monera, Classification and Features of Bacteria, Kingdom Protista. Study these first, then practise questions on each for Class 11 exams.
How should I revise Biological Classification for Class 11 exams?
Learn the core ideas first, then work through the 64 practice questions on Biological Classification. Revise definitions regularly and use flashcards for quick recall before the exam.
Sources & Official References
Content is aligned to the official syllabus. Refer to the board website for the latest curriculum.
More resources for Biological Classification
For serious students
Get the full Biological Classification chapter — start free.
Quizzes, flashcards, an AI doubt solver and a study plan for ICSE Class 11 Biology. Free to start, no card needed.