Class 6 Science Chapter 10 Notes
🌿 Living Creatures: Explorin
g their Characteristics
(New NCERT "Curiosity" | 2025-26)
📌 Chapter Overview
This chapter explores what makes a living being "alive" — and how living things are different from non-living things. Through the curiosity of Avadhi and Aayush, who begin by observing shells on a beach, students discover the key characteristics shared by all living organisms — movement, growth, nutrition, respiration, excretion, response to stimuli, and reproduction. The chapter also covers seed germination, life cycles of plants and animals (mosquito and frog), and animal adaptations.
💡 Opening Story: Avadhi and Aayush find beautiful shells on the beach and wonder — "A shell comes from a snail, which is a living creature. But the shell itself doesn't move or breathe — is it living or non-living?" This simple question opens a deep discussion about what it truly means to be alive!
🔑 Key Points
- All objects around us are either living or non-living
- Living beings have 7 main characteristics — movement, nutrition, growth, respiration, excretion, response to stimuli, reproduction
- Non-living things do not show these characteristics
- Plants also show movement — but not from place to place (called locomotion)
- Seed germination needs water, air, and suitable temperature
- Living organisms go through a life cycle — birth → growth → reproduction → death
- The process of major changes in body form during a life cycle is called Metamorphosis
- Animals adapt to their habitat through colour, body shape, and special features
🔎 10.1 Living and Non-Living Things
Everything around us can be divided into two groups:
| Category | Description | Examples |
|---|---|---|
| Living things | Show all life processes — grow, move, breathe, reproduce | Plants, animals, fungi, bacteria |
| Non-living things | Do NOT show life processes | Stone, chair, car, book, shell |
💡 Key Insight: A wooden log comes from a living tree, but the log itself is non-living — because its cells are dead and it can no longer perform any life process like growth, respiration, or reproduction.
Tricky cases:
- Seed → Living! (It can germinate and grow into a plant under the right conditions)
- Shell → Non-living! (It was made by a living snail, but the shell itself has no life processes)
- Egg → Living! (It can hatch and develop into an organism)
- Dried leaf → Non-living! (No longer performs life processes)
🔎 10.2 Characteristics of Living Beings
✅ Characteristic 1: Movement
- All living beings show movement
- In animals — movement of the whole body from one place to another = Locomotion
- Fish swim, birds fly, snakes crawl, humans walk
- In plants — no locomotion, but they show movement of parts:
- Sunflower turns toward the sun (phototropism)
- Roots grow downward (toward gravity)
- Shoot grows upward (toward light)
- Touch-me-not (Mimosa) folds its leaves when touched
- Insectivorous plants (like Drosera) trap insects by moving their leaves
- Flowers open and close
📌 Important: All living beings show movement but not all show locomotion. Movement is a broader term.
✅ Characteristic 2: Nutrition
- All living beings need food for energy, growth, and repair
- Animals eat plants or other animals (they cannot make their own food)
- Plants make their own food using sunlight, water, and carbon dioxide through Photosynthesis
- Nutrition provides energy for all life processes
✅ Characteristic 3: Growth
- All living beings grow — they increase in size and complexity over time
- Growth happens because living beings take in nutrition and use it to build more cells
- In animals → growth occurs throughout the body (baby grows into adult)
- In plants → growth mainly at tips of roots and shoots
- Non-living things can also increase in size (like a snowball rolling), but that is NOT growth — it is just accumulation of material from outside
💡 Key Difference: In living beings, growth happens from inside using nutrients. In non-living things, size increases by adding material from outside.
✅ Characteristic 4: Respiration
- All living beings need energy to carry out life processes
- This energy comes from respiration — the process of releasing energy from food
- Breathing = taking air in (inhaling) and pushing it out (exhaling)
- Respiration = using oxygen to break down food (glucose) → release energy + carbon dioxide + water
| Organism | How they respire |
|---|---|
| Humans / animals | Breathe through lungs or gills |
| Plants | Exchange gases through tiny pores called stomata on leaves |
| Fish | Breathe through gills |
| Dolphins/Whales | Breathe through lungs (come to surface for air) |
| Insects | Breathe through tiny holes called spiracles |
📌 Remember: Both plants and animals respire. Plants also take in oxygen and release carbon dioxide just like animals — but during daytime, photosynthesis produces more oxygen than respiration uses.
✅ Characteristic 5: Excretion
- Living beings produce waste products during life processes
- These waste products must be removed from the body — this is called Excretion
- If waste is not removed, it becomes toxic (poisonous) for the organism
| Organism | Waste products excreted |
|---|---|
| Humans | Urine (liquid), sweat, carbon dioxide |
| Plants | Oxygen (during photosynthesis), carbon dioxide (during respiration), water (through stomata) |
| Animals | Urine, sweat, carbon dioxide, feces |
✅ Characteristic 6: Response to Stimuli
- A stimulus is anything in the environment that causes a living being to react
- All living beings respond to stimuli — this shows they are aware of their surroundings
| Stimulus | Response |
|---|---|
| Touching something hot | Pulling hand away quickly |
| Bright light in eyes | Blinking / squinting |
| Touching a touch-me-not plant | Leaves fold immediately |
| Plant shoot near window | Grows toward light (phototropism) |
| Predator approaching | Animal runs away |
| Loud sound | Turning toward the sound |
💡 Non-living things do NOT respond to stimuli on their own. A stone hit by a ball moves because of an external force — not because it "responded."
✅ Characteristic 7: Reproduction
- All living beings produce new individuals of their own kind — this is called Reproduction
- Without reproduction, a species would go extinct
- It ensures continuity of life on Earth
| Type | Examples |
|---|---|
| Lay eggs | Frogs, mosquitoes, birds, fish |
| Give birth to young ones | Humans, dogs, cats, whales |
| Seeds and spores | Plants, fungi |
✅ What is Death?
- A living being is considered dead when it can no longer show the characteristics of life — even if food, air, and water are available
- Death = cessation of all life processes (breathing, growth, movement, response all stop)
🔎 10.3 Summary — Living vs Non-Living
| Characteristic | Living Things | Non-Living Things |
|---|---|---|
| Movement | Yes (locomotion or partial) | No (only if pushed/pulled) |
| Nutrition | Yes — need food | No |
| Growth | Yes — from inside | No (or only from outside) |
| Respiration | Yes — release energy | No |
| Excretion | Yes — remove waste | No |
| Response to stimuli | Yes | No |
| Reproduction | Yes | No |
🔎 10.4 Seed Germination
Germination = the process by which a seed sprouts and begins to grow into a new plant
✅ Conditions Needed for Germination:
| Condition | Why it is needed |
|---|---|
| Water | Softens seed coat; activates enzymes inside the seed; starts growth |
| Air (Oxygen) | Provides oxygen for respiration during germination |
| Suitable temperature | Too hot or too cold stops germination |
📌 Is light needed for germination?
- NO — light is NOT essential for germination
- Some seeds need light (Calendula, Zinnia — must be left uncovered)
- Some seeds need darkness (bean seeds — must be covered with soil)
- But after germination, sunlight IS essential for photosynthesis and further growth of the seedling
✅ Stages of Seed Germination:
Seed absorbs water → Seed coat softens → Embryo activates
→ Radicle (root) emerges first → Plumule (shoot) emerges
→ Seedling grows → Plant develops
✅ Why loosen soil before planting?
- Loosened soil has air pockets — provides oxygen for seed respiration
- Allows roots to penetrate easily
- Better water absorption
🔎 10.5 Life Cycle of Plants
A life cycle = the complete series of stages a living being goes through from birth to death
Seed → Germination → Seedling → Young Plant → Mature Plant
→ Flowers → Fruits (with seeds) → Seeds dispersed → New cycle begins
- Every plant produces seeds (through flowers and fruits) for the next generation
- The life cycle of a plant is continuous
🔎 10.6 Life Cycle of Animals
🦟 A) Life Cycle of a Mosquito (4 stages)
EGG → LARVA → PUPA → ADULT MOSQUITO
| Stage | Where | Features |
|---|---|---|
| Egg | On stagnant water | Female lays eggs in clusters on still water |
| Larva | In water | Wriggles in water; feeds; breathes through a tube at surface |
| Pupa | In water | Comma-shaped; does not feed; transformation occurs inside |
| Adult | On land and air | Wings develop; flies; female bites for blood |
⚠️ Health Alert: Female mosquitoes transmit diseases like Malaria and Dengue. They breed in stagnant water (coolers, pots, puddles). To disrupt their life cycle: remove stagnant water, use larvicides, use mosquito nets.
🐸 B) Life Cycle of a Frog (5 stages)
EGG (Spawn) → EMBRYO → TADPOLE → FROGLET → ADULT FROG
| Stage | Features |
|---|---|
| Egg (Spawn) | Cluster of eggs laid in water; jelly-like coating protects them |
| Embryo | Develops inside the egg; 2–5 days |
| Tadpole | Hatches from egg; lives in water; breathes through gills; has a tail for swimming; looks like a fish |
| Froglet | Legs develop; tail shrinks; starts coming to land; develops lungs |
| Adult Frog | Fully developed; lives on land and water (amphibian); breathes through lungs; reproduces |
💡 Key difference between mosquito and frog life cycle:
- Both undergo metamorphosis (dramatic changes in body form)
- Mosquito has 4 stages; Frog has 5 stages
- Tadpoles breathe through gills; adult frogs through lungs and skin
- Tadpole has a tail for swimming; adult frog has legs for jumping
🦋 C) Life Cycle of a Silk Moth / Butterfly (4 stages)
EGG → LARVA (Caterpillar) → PUPA (Cocoon) → ADULT
| Stage | Features |
|---|---|
| Egg | Laid on leaves |
| Larva (Caterpillar) | Feeds on leaves; grows; secretes silk to form a cocoon |
| Pupa (Cocoon) | Transformation occurs inside cocoon; does not feed |
| Adult | Emerges from cocoon; mates; lays eggs to continue cycle |
📌 Silk is obtained from the cocoon of the silk moth (Bombyx mori). India is one of the largest producers of silk — this is called Sericulture!
🔎 10.7 What is Metamorphosis?
- Metamorphosis = the process in which an organism undergoes significant changes in body form during different stages of its life cycle
- Examples: mosquito, butterfly, silk moth, frog — all undergo metamorphosis
- The young ones look completely different from the adults (e.g., tadpole ≠ frog)
🔎 10.8 Adaptation — How Animals Survive in Their Habitat
Adaptation = special features in animals that help them survive in their environment
| Animal | Habitat | Adaptation |
|---|---|---|
| Camel | Desert | Stores fat in hump; excretes less water; long eyelashes block sand |
| Polar bear | Arctic | Thick white fur for warmth and camouflage |
| Duck | Water | Webbed feet for swimming |
| Eagle | Sky/mountains | Sharp eyesight; curved beak and talons for hunting |
| Fish | Water | Streamlined body; gills for breathing |
| Frog | Land and water | Can breathe through skin and lungs |
Camouflage = ability to blend into surroundings to hide from predators
- Examples: Chameleon changes colour; green grasshopper on grass; stick insect looks like a twig
📖 Important Definitions
| Term | Definition |
|---|---|
| Living things | Organisms that show all life processes — movement, growth, respiration, excretion, reproduction, response to stimuli |
| Non-living things | Objects that do not show life processes |
| Movement | Change in position or location of an organism or its parts |
| Locomotion | Movement of the whole body from one place to another |
| Nutrition | Process of obtaining and using food for energy, growth, and maintenance |
| Photosynthesis | Process by which plants make food using sunlight, water, and CO₂ |
| Respiration | Process of releasing energy from food using oxygen |
| Breathing | Physical act of taking air in and pushing it out |
| Stomata | Tiny pores on leaf surface used for gas exchange in plants |
| Excretion | Removal of waste products from the body |
| Stimulus | Anything that causes a living being to react or respond |
| Reproduction | Process of producing new individuals of the same kind |
| Germination | Process by which a seed sprouts and begins to grow into a plant |
| Life Cycle | Complete series of stages from birth to death of an organism |
| Metamorphosis | Significant changes in body form during different stages of a life cycle |
| Adaptation | Special features that help an organism survive in its habitat |
| Camouflage | Ability to blend into surroundings to avoid being seen |
| Phototropism | Growth of a plant toward light |
| Spawn | Cluster of frog eggs laid in water |
| Tadpole | Larval stage of a frog — lives in water, breathes through gills |
❓ NCERT Exercise Questions & Answers
Q1. How would you now categorise a seed — as living or non-living?
Answer: A seed is a living thing. Even though it may appear inactive, it has a tiny embryo inside which can germinate and grow into a full plant when given the right conditions (water, air, and suitable temperature). It carries out life processes when conditions are favourable. So a seed is a living organism in a dormant state.
Q2. How can the life cycle of a mosquito be disrupted?
Answer: The life cycle of a mosquito can be disrupted by:
- Removing stagnant water from coolers, pots, tyres, and puddles — mosquitoes need still water to lay eggs
- Using larvicides — chemicals that kill the larvae in breeding water before they grow into adults
- Covering water storage containers — prevents mosquitoes from laying eggs
- Using mosquito nets and repellents — prevents adult mosquitoes from biting
Q3. What are the similarities and differences in the life cycles of a mosquito and a frog?
Answer:
Similarities:
- Both undergo metamorphosis (dramatic body changes across stages)
- Both begin life as eggs
- Both have an aquatic larval stage (larva/tadpole live in water)
- Both go through multiple stages before becoming adults
Differences:
| Feature | Mosquito | Frog |
|---|---|---|
| Number of stages | 4 (Egg → Larva → Pupa → Adult) | 5 (Egg → Embryo → Tadpole → Froglet → Adult) |
| Pupa stage | Yes | No |
| Larva breathes | Through a breathing tube at water surface | Through gills (tadpole) |
| Adult habitat | Land and air | Land and water (amphibian) |
| Movement of larva | Wriggles in water | Swims using tail |
Q4. Charan says a wooden log is non-living as it cannot move. Charu says it is living because it is made of wood from trees. Who is correct?
Answer:
- Charan is correct — A wooden log is non-living because it cannot perform any life process — it does not grow, respire, reproduce, or respond to stimuli. The cells in the wood are all dead.
- Charu is not correct — Although wood originally came from a living tree, the log itself has no life processes. The source of a material does not decide whether it is living or non-living. What matters is whether it currently performs life processes.
Q5. What is the correct sequence of the life cycle of a frog?
Answer: Egg (Spawn) → Embryo → Tadpole → Froglet → Adult Frog
Q6. Why does the tadpole have a tail? What happens to it later?
Answer: The tadpole has a tail because it lives in water — the tail helps it swim and move around, find food, and escape from predators. As the tadpole grows into a froglet, legs begin to develop and the tail gradually shrinks and disappears. The adult frog uses its legs to move instead.
Q7. What distinguishes living things from non-living things?
Answer: Living things are distinguished from non-living things by these characteristics:
- They move on their own (or show movement in parts)
- They grow by taking in nutrition
- They respire to release energy from food
- They excrete waste products
- They respond to stimuli (react to changes in surroundings)
- They reproduce to produce offspring Non-living things do none of these on their own.
✅ MCQ Questions
1. Which of the following is a characteristic of ALL living things? a) They can fly b) They grow and reproduce ✅ c) They can change colour d) They can be moved by wind
2. Movement of a plant toward light is called: a) Geotropism b) Phototropism ✅ c) Hydrotropism d) Metamorphosis
3. Tiny pores on the leaf surface used for gas exchange are called: a) Spiracles b) Stomata ✅ c) Gills d) Lungs
4. Which is NOT needed for seed germination? a) Water b) Air c) Sunlight ✅ d) Suitable temperature
5. Tadpoles breathe using: a) Lungs b) Spiracles c) Stomata d) Gills ✅
6. The process of significant body changes during life stages is called: a) Reproduction b) Metamorphosis ✅ c) Germination d) Adaptation
7. A mosquito lays its eggs in: a) Soil b) Stagnant water ✅ c) Moving rivers d) Sand
8. Which of these is a living thing? a) Wooden log b) Shell c) Seed ✅ d) Dried leaf
9. Respiration in plants occurs through: a) Roots b) Flowers c) Seeds d) Stomata ✅
10. The process in which organisms change form during their life cycle is: a) Life span b) Germination c) Metamorphosis ✅ d) Excretion
11. Which animal uses camouflage to hide from predators? a) Elephant b) Chameleon ✅ c) Dolphin d) Eagle
12. The larval stage of a butterfly is called: a) Pupa b) Spawn c) Caterpillar ✅ d) Froglet
🧠 Quick Revision Table
| Characteristic | In Animals | In Plants |
|---|---|---|
| Movement | Locomotion (whole body) | Parts only (phototropism, touch response) |
| Nutrition | Eat food (plants/animals) | Make food by photosynthesis |
| Respiration | Lungs, gills, spiracles | Stomata on leaves |
| Excretion | Urine, sweat, CO₂ | O₂ (photosynthesis), CO₂ (respiration), water |
| Response | React to touch, light, sound | Touch-me-not folds, shoot bends toward light |
| Reproduction | Eggs or live birth | Seeds, spores |
| Growth | Whole body grows | Mainly at root and shoot tips |
🔴 Life Cycle Summary
| Organism | Stages | Special Feature |
|---|---|---|
| Mosquito | Egg → Larva → Pupa → Adult | Breeds in stagnant water; spreads malaria/dengue |
| Frog | Egg → Embryo → Tadpole → Froglet → Adult | Tadpole has gills + tail; adult has lungs + legs |
| Butterfly / Silk Moth | Egg → Larva → Pupa → Adult | Silk from cocoon; complete metamorphosis |
| Plant | Seed → Seedling → Plant → Flower → Fruit → Seed | Cycle repeats each generation |
🌟 Ancient Indian Connection!
Sericulture — the art of silk production from silk moth cocoons — has been practised in India for over 5,000 years! Ancient Indian texts describe the rearing of silk moths. India is the second largest producer of silk in the world. The state of Odisha is famous for its Tussar silk (also called Kosa silk) — a wild silk made from the cocoons of the Antheraea moth that feeds on forest trees — making it an eco-friendly and sustainable fabric! 🇮🇳
📌 Exam Tips
- Most asked: "Why is a seed living?" → Because it can germinate and grow under right conditions
- Know all 7 characteristics of living beings with one example each — very frequently asked!
- Phototropism definition with example (sunflower / shoot bending toward light) is important
- Frog life cycle with all 5 stages in correct order is commonly asked — don't mix up with mosquito (4 stages)
- Remember: Light is NOT needed for germination — but IS needed for growth after germination
- Wooden log = non-living (even though from a tree) — this tricky question always appears! 🎯