📌 Chapter Overview
The world around us is full of an incredible variety of living things — from tiny bacteria to giant whales, from small grass to tall trees. This chapter explores the diversity of life on Earth, how living things are different from non-living things, and how scientists classify living organisms to study them better.
🔑 Key Points / Summary
- There is a huge variety of living organisms on Earth
- Living things are different from non-living things
- All living things share certain common characteristics
- Scientists classify (group) living organisms to study them easily
- Living organisms are broadly divided into Plants, Animals and Microorganisms
- Plants are further classified based on their features
- Animals are classified as vertebrates and invertebrates
❓ What is Diversity?
- Diversity means variety or difference
- The living world shows enormous diversity — different shapes, sizes, colours, habitats and behaviours
- From the tiniest bacteria (too small to see) to the blue whale (largest animal), life exists in every corner of Earth
- This variety of life on Earth is called Biodiversity
🆚 Living vs Non-Living Things
Living Things:
Things that are alive — they grow, breathe, eat, reproduce and respond to changes.
Non-Living Things:
Things that are not alive — they do not grow, breathe or reproduce.
| Feature | Living Things | Non-Living Things |
|---|---|---|
| Growth | ✅ Yes | ❌ No |
| Breathing/Respiration | ✅ Yes | ❌ No |
| Movement | ✅ Yes | ❌ No (mostly) |
| Reproduction | ✅ Yes | ❌ No |
| Response to surroundings | ✅ Yes | ❌ No |
| Need food/energy | ✅ Yes | ❌ No |
| Made of cells | ✅ Yes | ❌ No |
💡 Tricky Example: Fire moves and grows but is NOT living because it cannot reproduce or respond like living beings. A car moves but is NOT living.
✅ Characteristics of Living Things
All living organisms share these features:
1. 🌱 Growth
- All living things grow over time
- Plants grow from seeds → seedlings → big plants
- Animals grow from young ones → adults
2. 🫁 Respiration
- All living things breathe (take in oxygen and release carbon dioxide)
- Animals breathe through lungs, gills etc.
- Plants breathe through tiny pores called stomata
3. 🍎 Nutrition
- All living things need food/energy to survive
- Plants make their own food (photosynthesis)
- Animals eat plants or other animals
4. 👶 Reproduction
- All living things produce young ones (babies/offspring)
- This ensures the species continues to exist
5. 🏃 Movement
- All living things move in some way
- Animals move from place to place
- Plants move slowly — they turn towards sunlight
6. 💡 Response to Stimuli
- All living things respond to changes around them
- Example: Touch-me-not plant folds its leaves when touched
- Example: We feel pain when hurt
7. ⚰️ Death
- All living things have a lifespan and eventually die
🗂️ Classification of Living Things
With millions of living organisms on Earth, scientists needed a system to organise and study them. This is called Classification.
Why Do We Classify?
- To organise the huge variety of living things
- To study them more easily
- To understand relationships between different organisms
- To identify new organisms easily
Who is the Father of Classification?
🏆 Carl Linnaeus is called the "Father of Classification" (or Father of Taxonomy)
🌳 Major Groups of Living Things
Living things are broadly grouped as:
ALL LIVING THINGS
├── 🦠 Microorganisms (Bacteria, Fungi, Protozoa)
├── 🌿 Plants (Kingdom Plantae)
└── 🐾 Animals (Kingdom Animalia)
🌿 Classification of Plants
Plants are classified based on whether they have proper roots, stems, leaves and seeds:
Group 1: Plants Without Seeds
| Type | Features | Examples |
|---|---|---|
| Algae | Live in water, no roots/stems/leaves | Seaweed, Spirogyra |
| Mosses (Bryophytes) | Small, live in damp places, no true roots | Moss |
| Ferns (Pteridophytes) | Have stems and leaves, no seeds | Fern |
Group 2: Plants With Seeds
| Type | Features | Examples |
|---|---|---|
| Gymnosperms | Seeds are naked (not inside fruit) | Pine, Deodar, Cycas |
| Angiosperms | Seeds inside fruits/flowers | Mango, Rose, Wheat |
Angiosperms are Further Divided:
| Type | Features | Examples |
|---|---|---|
| Monocots | One seed leaf, parallel veins | Grass, Wheat, Maize, Rice |
| Dicots | Two seed leaves, branched veins | Mango, Rose, Peas, Sunflower |
🌱 Types of Plants by Size
| Type | Features | Examples |
|---|---|---|
| Herbs | Small, soft stem, short life | Grass, Wheat, Tulsi |
| Shrubs | Medium size, woody but not very tall | Rose, Lemon, Henna |
| Trees | Tall, thick woody trunk | Mango, Banyan, Neem |
| Climbers | Weak stem, climb using support | Money plant, Pea, Grape |
| Creepers | Weak stem, spread on ground | Pumpkin, Watermelon |
🐾 Classification of Animals
Animals are first divided into two big groups:
1. 🦴 Vertebrates (Animals WITH a backbone)
Animals that have a backbone (spine) inside their body.
| Class | Features | Examples |
|---|---|---|
| Fish | Live in water, breathe through gills, scales | Rohu, Shark, Goldfish |
| Amphibians | Live on land AND water, moist skin | Frog, Toad, Salamander |
| Reptiles | Dry scaly skin, lay eggs on land | Snake, Lizard, Crocodile, Turtle |
| Birds | Feathers, wings, lay eggs, warm-blooded | Sparrow, Eagle, Ostrich |
| Mammals | Give birth to young ones, feed milk, warm-blooded | Human, Cow, Whale, Bat |
2. 🐛 Invertebrates (Animals WITHOUT a backbone)
Animals that do NOT have a backbone.
| Group | Examples |
|---|---|
| Insects | Butterfly, Ant, Mosquito, Bee |
| Worms | Earthworm, Tapeworm |
| Molluscs | Snail, Octopus, Squid |
| Crustaceans | Crab, Prawn, Lobster |
| Echinoderms | Starfish, Sea urchin |
💡 Remember: About 95% of all animals are invertebrates! Only 5% are vertebrates.
🦠 Microorganisms
- Living organisms that are too small to see with the naked eye
- Also called microbes
- Need a microscope to see them
- Found everywhere — in air, water, soil, inside our body
| Type | Examples | Role |
|---|---|---|
| Bacteria | Lactobacillus | Makes curd, causes diseases |
| Fungi | Yeast, Mushroom | Makes bread, causes infections |
| Protozoa | Amoeba | Lives in water |
| Algae | Spirogyra | Produces oxygen in water |
| Virus | Influenza virus | Causes diseases (cold, flu) |
🌍 Habitats and Diversity
Living organisms are found in different habitats (places where they live):
| Habitat | Examples of Living Things |
|---|---|
| Forest | Tiger, Deer, Oak tree, Ferns |
| Desert | Camel, Cactus, Scorpion |
| Ocean/Sea | Whale, Coral, Seaweed, Fish |
| Freshwater | Frog, Lotus, Crocodile |
| Grassland | Lion, Elephant, Grass |
| Mountain | Snow leopard, Pine tree, Yak |
| Polar regions | Polar bear, Penguin |
📖 Important Definitions
| Term | Definition |
|---|---|
| Diversity | A wide variety of different living things |
| Biodiversity | The variety of all living organisms on Earth |
| Classification | The process of grouping living things based on similarities |
| Taxonomy | The science of classifying living organisms |
| Vertebrate | Animal with a backbone |
| Invertebrate | Animal without a backbone |
| Habitat | The natural home/environment of a living organism |
| Microorganism | A living thing too small to see without a microscope |
| Photosynthesis | The process by which plants make their own food using sunlight |
| Stomata | Tiny pores on leaves through which plants breathe |
| Stimulus | A change in the environment that a living thing responds to |
🌟 Important Extra Questions & Answers
Q1. What is biodiversity? Why is it important?
Answer: Biodiversity means the variety of all living organisms found on Earth. It is important because:
- Different organisms depend on each other for food and survival
- Plants produce oxygen that animals need to breathe
- Many medicines come from plants and animals
- It keeps the environment balanced
Q2. What is classification? Why do scientists classify living things?
Answer: Classification is the process of grouping living organisms based on their similarities and differences. Scientists classify living things because:
- There are millions of species — it is impossible to study them individually
- Classification makes it easier to identify and study organisms
- It helps us understand how different organisms are related to each other
Q3. What is the difference between vertebrates and invertebrates? Give two examples each.
Answer:
- Vertebrates have a backbone inside their body. Examples: Fish, Bird
- Invertebrates do not have a backbone. Examples: Earthworm, Butterfly
Q4. How are plants different from animals?
Answer:
| Plants | Animals |
|---|---|
| Make their own food (photosynthesis) | Cannot make their own food |
| Generally cannot move from place to place | Can move from place to place |
| Breathe through stomata | Breathe through lungs/gills |
| Have chlorophyll (green colour) | No chlorophyll |
Q5. Name the five groups of vertebrates with one example each.
Answer:
- Fish → Rohu
- Amphibians → Frog
- Reptiles → Snake
- Birds → Sparrow
- Mammals → Human being
✅ MCQ Questions
1. Which of the following is a characteristic of ALL living things? a) They can fly b) They have green colour c) They reproduce d) They live in water
✅ Answer: c) They reproduce
2. The Father of Classification is: a) Charles Darwin b) Carl Linnaeus c) Gregor Mendel d) Isaac Newton
✅ Answer: b) Carl Linnaeus
3. Which of the following is an invertebrate? a) Frog b) Snake c) Butterfly d) Fish
✅ Answer: c) Butterfly
4. Plants breathe through tiny pores called: a) Roots b) Stomata c) Veins d) Petals
✅ Answer: b) Stomata
5. Which group of plants has naked seeds (not inside fruit)? a) Algae b) Mosses c) Gymnosperms d) Angiosperms
✅ Answer: c) Gymnosperms
6. Which of the following is a mammal? a) Crocodile b) Shark c) Bat d) Eagle
✅ Answer: c) Bat
7. Microorganisms can be seen with: a) Naked eye b) Telescope c) Microscope d) Binoculars
✅ Answer: c) Microscope
8. A cactus plant is found in which habitat? a) Ocean b) Forest c) Desert d) Mountain
✅ Answer: c) Desert
🧠 Quick Revision Table
| Topic | Key Point |
|---|---|
| Biodiversity | Variety of all life on Earth |
| Classification | Grouping organisms by similarities |
| Father of Classification | Carl Linnaeus |
| Living characteristics | Growth, Respiration, Nutrition, Reproduction, Movement, Response |
| Vertebrates | Fish, Amphibia, Reptiles, Birds, Mammals |
| Invertebrates | Insects, Worms, Molluscs, Crustaceans |
| Plant types | Herbs, Shrubs, Trees, Climbers, Creepers |
| Microorganisms | Bacteria, Fungi, Algae, Protozoa, Virus |
📌 Exam Tips:
- Always remember 7 characteristics of living things
- Learn 5 classes of vertebrates with examples
- Difference between vertebrates and invertebrates is a favourite exam question
- Remember Carl Linnaeus as Father of Classification 🎯