Science Curiosity Notes Class 6 English Medium 2026-27

Science Curiosity Chapter 2. Diversity in the Living World

CBSE Notes New Syllabus: Class 6

Assignments - What Have You Learned?

Chapter 2. Diversity in the Living World

Living organisms around us are different in size, shape, habitat, and food habits. To make their study easy, scientists classify them into different groups based on their common characteristics.

Detailed Notes

Diversity in the Living World

Diversity in the Living World: The presence of many different kinds of living organisms on Earth is called diversity in the living world.

Examples of Living Organisms

(i) Plants

(ii) Animals

(iii) Birds

(iv) Insects

(v) Microorganisms

Characteristics of Diversity

(i) Living organisms differ in size and shape.

(ii) They live in different habitats.

(iii) They have different food habits.

(iv) They show different ways of movement.

Biodiversity

Biodiversity: Biodiversity is the variety of plants, animals, and microorganisms found in a region.

Importance of Biodiversity

(i) Maintains ecological balance.

(ii) Supports the food chain.

(iii) Provides food and medicines.

(iv) Protects natural resources.

Examples of Biodiversity

(i) Forests

(ii) Grasslands

(iii) Rivers

(iv) Oceans

Classification of Living Organisms

Classification: Classification is the process of grouping living organisms based on their similar characteristics.

Need for Classification

(i) Makes the study of organisms easy.

(ii) Helps identify organisms correctly.

(iii) Shows similarities and differences.

(iv) Helps scientists study new organisms.

Basis of Classification

(i) Body structure

(ii) Habitat

(iii) Food habits

(iv) Reproduction

Classification of Plants

Classification of Plants: Plants are grouped according to the nature of their stem and growth habit.

Major Groups of Plants

(i) Herbs

(ii) Shrubs

(iii) Trees

(iv) Climbers

(v) Creepers

Herbs

Herbs: Herbs are small plants with soft and green stems.

Examples of Herbs

(i) Spinach

(ii) Coriander

(iii) Tomato

(iv) Wheat

(v) Rice

Characteristics of Herbs

(i) Small in size.

(ii) Soft and tender stem.

(iii) Usually live for a short period.

Shrubs

Shrubs: Shrubs are medium-sized plants with hard and woody stems.

Examples of Shrubs

(i) Rose

(ii) Tulsi

(iii) Hibiscus

(iv) Henna

Characteristics of Shrubs

(i) Medium-sized plants.

(ii) Woody stems.

(iii) Branches grow near the base.

Trees

Trees: Trees are tall plants with a thick woody stem called a trunk.

Examples of Trees

(i) Mango

(ii) Neem

(iii) Banyan

(iv) Peepal

Characteristics of Trees

(i) Tall and strong plants.

(ii) Thick woody trunk.

(iii) Branches grow above the ground.

Key Points

(i) Earth has many kinds of living organisms.

(ii) Biodiversity is important for nature.

(iii) Classification makes the study of organisms easier.

(iv) Plants are grouped into herbs, shrubs, trees, climbers, and creepers.

(v) Herbs have soft stems, while trees have thick trunks.

Climbers

Climbers: Climbers are plants with weak stems that need support to grow upward.

Examples of Climbers

(i) Grapevine

(ii) Pea Plant

(iii) Money Plant

(iv) Bean Plant

Characteristics of Climbers

(i) Have weak stems.

(ii) Cannot stand upright.

(iii) Grow with the support of sticks, walls, or other plants.

Creepers

Creepers: Creepers are plants with very weak stems that grow along the ground.

Examples of Creepers

(i) Pumpkin

(ii) Watermelon

(iii) Muskmelon

(iv) Bottle Gourd

Characteristics of Creepers

(i) Have very weak stems.

(ii) Spread on the ground.

(iii) Produce large and heavy fruits.

Leaf Venation

Leaf Venation: The arrangement of veins on a leaf is called leaf venation.

Types of Leaf Venation

(i) Reticulate Venation

(ii) Parallel Venation

Reticulate Venation

Reticulate Venation: In this type, the veins form a network-like pattern on the leaf.

Examples of Reticulate Venation

(i) Mango

(ii) Rose

(iii) Mustard

(iv) Hibiscus

Characteristics of Reticulate Venation

(i) Veins form a network.

(ii) Mostly found in dicot plants.

Parallel Venation

Parallel Venation: In this type, the veins run parallel to each other from the base to the tip of the leaf.

Examples of Parallel Venation

(i) Wheat

(ii) Rice

(iii) Maize

(iv) Banana

Characteristics of Parallel Venation

(i) Veins run side by side.

(ii) Mostly found in monocot plants.

Root System

Root System: The root system is the underground part of a plant that absorbs water and minerals and holds the plant firmly in the soil.

Functions of Roots

(i) Fix the plant in the soil.

(ii) Absorb water and minerals.

(iii) Store food in some plants.

Types of Root System

(i) Tap Root System

(ii) Fibrous Root System

Tap Root System

Tap Root System: A root system with one main root and many smaller side roots is called a tap root system.

Examples of Tap Root

(i) Mustard

(ii) Gram

(iii) Radish

(iv) Carrot

Characteristics of Tap Root

(i) Has one thick main root.

(ii) Smaller roots arise from the main root.

(iii) Common in dicot plants.

Fibrous Root System

Fibrous Root System: A root system made up of many thin roots of nearly the same size is called a fibrous root system.

Examples of Fibrous Root

(i) Wheat

(ii) Rice

(iii) Maize

(iv) Grass

Characteristics of Fibrous Root

(i) No main root is present.

(ii) All roots are nearly equal in size.

(iii) Common in monocot plants.

Key Points

(i) Climbers need support to grow upward.

(ii) Creepers spread along the ground.

(iii) Leaves show reticulate or parallel venation.

(iv) Roots absorb water and minerals.

(v) Plants have either a tap root or a fibrous root system.

Cotyledon

Cotyledon: A cotyledon is the seed leaf that stores food for the growing plant.

Importance of Cotyledons

(i) Store food for the young plant.

(ii) Help the seed germinate.

(iii) Support the early growth of the seedling.

Classification of Plants Based on Cotyledons

Classification Based on Cotyledons: Plants are grouped into monocots and dicots according to the number of cotyledons in their seeds.

Types of Plants

(i) Monocot Plants

(ii) Dicot Plants

Monocot Plants

Monocot Plants: Monocot plants have one cotyledon in their seeds.

Characteristics of Monocot Plants

(i) Have one cotyledon.

(ii) Show parallel venation.

(iii) Have a fibrous root system.

Examples of Monocot Plants

(i) Wheat

(ii) Rice

(iii) Maize

(iv) Banana

Dicot Plants

Dicot Plants: Dicot plants have two cotyledons in their seeds.

Characteristics of Dicot Plants

(i) Have two cotyledons.

(ii) Show reticulate venation.

(iii) Have a tap root system.

Examples of Dicot Plants

(i) Gram

(ii) Pea

(iii) Mustard

(iv) Mango

Difference Between Monocot and Dicot Plants

Relationship Between Leaf Venation and Root System

Relationship: Leaf venation is generally related to the type of root system in a plant.

Important Relationships

(i) Reticulate Venation → Tap Root → Dicot Plant.

(ii) Parallel Venation → Fibrous Root → Monocot Plant.

Nature Conservation

Nature Conservation: Nature conservation means protecting plants, animals, and their habitats.

Importance of Nature Conservation

(i) Protects biodiversity.

(ii) Maintains ecological balance.

(iii) Saves endangered species.

(iv) Protects natural resources.

Ways to Conserve Nature

(i) Plant more trees.

(ii) Avoid cutting forests.

(iii) Protect wildlife.

(iv) Reduce pollution.

(v) Use natural resources wisely.

Chapter Summary

Important Points

(i) Earth has a great diversity of living organisms.

(ii) Biodiversity is essential for a healthy environment.

(iii) Classification helps us study living organisms easily.

(iv) Plants are classified as herbs, shrubs, trees, climbers, and creepers.

(v) Leaves show reticulate or parallel venation.

(vi) Plants have tap root or fibrous root systems.

(vii) Monocots have one cotyledon, while dicots have two cotyledons.

(viii) Parallel venation is usually associated with fibrous roots.

(ix) Reticulate venation is usually associated with tap roots.

(x) Conserving biodiversity helps maintain the balance of nature.