# The Living World Notes, Class 11 Biology | SwaVid

The Living World, NCERT Class 11 Biology: notes with key ideas, key terms, common mistakes and 3 quick checks with worked answers.

Canonical: https://www.swavid.com/cbse/class-11/biology/chapter/the-living-world

Source: https://www.swavid.com/cbse/class-11/biology/chapter/the-living-world

# The Living World

## Key terms

## Key ideas

## Common mistakes

## Quick checks

## Keep going

## Questions parents ask

## Class 11 Biology on SwaVid

### Biodiversity and identification

### Nomenclature and codes

### Rules of binomial nomenclature

### Taxonomy and systematics

### Taxonomic hierarchy

### Next chapter

### Related chapter

### Related chapter

### All chapters

SwaVid › CBSE › Class 11 › Biology › The Living World

Notes written by SwaVid from the NCERT textbook.

Class 11 Biology, Chapter 1. Key ideas, formulas and common mistakes.

CBSE prints 15 marks for Unit I, not for this chapter alone.

Short answer. This chapter introduces biodiversity, the scientific naming of organisms, and the hierarchical system of biological classification. It teaches how binomial nomenclature standardises names across the world and how organisms are arranged into taxonomic categories from species to kingdom.

Source: NCERT Biology (Reprint 2026-27) , Chapter 1, The Living World

The number of known and described species ranges from 1.7 to 1.8 million. Standardised naming ensures that an organism is known by the same single name everywhere, which requires accurate identification first.

Scientific naming follows international codes: ICBN for plants and ICZN for animals. Each scientific name has two components, the generic name and the specific epithet.

Biological names are generally in Latin and written in italics or separately underlined when handwritten. The genus starts with a capital letter, while the specific epithet begins with a small letter.

Taxonomy deals with characterisation, identification, nomenclature, and classification into taxa. Systematics takes into account evolutionary relationships among organisms alongside traditional taxonomic studies.

Classification involves a hierarchy of steps where each step represents a category or rank called a taxon. The ascending order of obligate categories is species, genus, family, order, class, phylum or division, and kingdom.

Try each question first. Then tap it to see the answer.

Check capitalisation: The specific epithet must start with a small letter, so 'Tuberosum' should be 'tuberosum'.

Check underlining rule: The genus name and specific epithet must be underlined separately, not with a single continuous line.

The specific epithet 'tuberosum' must begin with a lowercase letter, and both parts must be underlined separately.

Ascending order means starting from the lowest basic category to the highest category.

Order: Species, Genus, Family, Order, Class, Phylum, Kingdom.

Species → Genus → Family → Order → Class → Phylum → Kingdom

In Homo sapiens, the first word denotes the genus, which is Homo.

According to the NCERT taxonomy table, the family of humans is Hominidae.

Genus: Homo; Family: Hominidae

Biological Classification .

Plant Kingdom .

Animal Kingdom .

The 19 chapters of Class 11 Biology .

CBSE does not give marks to one chapter. It prints 15 marks for Unit I, Diversity of Living Organisms, which includes The Living World.

No. They are written by SwaVid from the NCERT textbook. The CBSE curriculum is the reference for what is assessed.

Biological Classification.

SwaVid is an AI tutor for Indian students in Classes 6 to 12. It finds the earlier ideas a child missed, then teaches today’s chapter. Start free to see how it works.

- Ch 1 NCERT book
- 15 marks, Unit I
- 3 quick checks
- Capitalising the specific epithet in a scientific name . Always write the genus name with an initial capital letter and the specific epithet entirely in lowercase letters, for example, Mangifera indica.
- Drawing a single continuous underline under a handwritten scientific name . Underline the genus name and the specific epithet separately when writing names by hand to indicate their Latin origin.
- Using phylum instead of division for plants . In botanical classification, use the term division for the category that corresponds to phylum in animals.
- Thinking the number of shared characteristics increases from species to kingdom . Common characteristics decrease as you move up the hierarchy from species to kingdom; members of higher taxa share fewer similarities.

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