StudyOSStudyOS CBSE Study Material, Class 5–12

Living Creatures: Exploring their Characteristics

NCERT Class 6 · Science Based on NCERT Class 6 Science textbook · Free CBSE study kit

Everything you need to ace this chapter, in one place.
Notes · Mind Map · Quiz · Assertion-Reason · Case Studies · Question Bank · Past Papers

Get Full Study Kit →
Studying with friends? Send them this chapter.

Chapter Notes

Overview
This chapter introduces students to the fundamental characteristics that distinguish living beings from non-living things. It explains that all living beings share common features such as movement, growth, nutrition, respiration, excretion, response to stimuli, reproduction, and eventual death. The big idea is that a student must be able to classify anything in their surroundings as living or non-living by checking for these essential characteristics, and understand that even plants and animals undergo life cycles with distinct stages.
Key Concepts (24)
Living
Things that show all the essential characteristics of life such as movement, growth, nutrition, respiration, excretion, response to stimuli, reproduction, and eventually die.
e.g. A pigeon, a bean plant, a dog, a human being.
Non-living
Things that do not show any of the essential characteristics of life like growth, respiration, reproduction, or response to stimuli.
e.g. A pencil, a book, a car, a chair.
Movement
The ability of a living being to change its position or the position of its body parts. In animals, it often means moving from one place to another; in plants, it includes opening of flowers, growth of shoots towards light, and folding of leaves.
e.g. A dog running, a sunflower turning towards the sun, a touch-me-not plant folding its leaves when touched.
Growth
A permanent increase in the size or mass of a living being over time. All living beings grow, though the rate and pattern may differ.
e.g. A child becoming taller and heavier, a seed growing into a plant, a puppy growing into a dog.
Nutrition
The process by which living beings obtain and use food for growth, energy, and development.
e.g. Humans eat rice and vegetables; plants make their own food using sunlight; a cow eats grass.
Respiration
The process by which living beings take in air (oxygen) from the surroundings and release energy from food. Breathing is a part of respiration.
e.g. Humans inhale and exhale air; plants have tiny pores called stomata on leaves for gas exchange.
Breathing
The physical process of taking air into the body (inhalation) and pushing air out of the body (exhalation). It is part of respiration.
e.g. Counting the number of breaths per minute after walking or running.
Excretion
The process of removing waste products from the body. Living beings produce waste that must be eliminated.
e.g. Humans sweat and pass urine; plants excrete excess water and minerals as droplets on leaves (e.g., grass, rose).
Stimulus
Any thing or any event that prompts a living being to respond. The plural is stimuli.
e.g. Stepping on a thorn (stimulus) causes you to pull your foot away (response); touching a hot cup of tea (stimulus) makes you withdraw your hand (response).
Response
The reaction of a living being to a stimulus.
e.g. A touch-me-not plant folding its leaves when touched is a response to the stimulus of touch.
Reproduction
The process by which living beings produce new individuals of their own kind. It is necessary for the continuity of life.
e.g. A cat giving birth to kittens; a bean plant producing seeds that grow into new bean plants.
Death
The end of all life processes in a living being. When a living being is not able to exhibit any characteristics of life despite the availability of all resources, it is said to be dead.
e.g. A plant that becomes yellow and dry and stops growing even after watering is dead.
Germination
The process by which a seed develops into a sprout or a young plant. It is the beginning of a plant's life cycle.
e.g. A bean seed placed in moist soil in sunlight germinates and produces a seedling with a root and a shoot.
Seed coat
The outer covering of a seed that protects the tiny embryo inside. Water softens the seed coat during germination.
e.g. The hard outer layer of a bean seed that splits open when the seed germinates.
Embryo
The tiny, undeveloped plant inside a seed that grows into a new plant when conditions are favourable.
e.g. Inside a bean seed, the embryo is the part that develops into the root and shoot.
Stomata
Tiny pores on the surface of leaves that help plants take in air and release gases. They are involved in respiration.
e.g. The small openings on a rose leaf that allow the plant to breathe.
Life cycle
The entire sequence of stages a living being goes through from birth or germination to death, including reproduction.
e.g. A bean plant's life cycle: seed → germination → seedling → flowering → fruit with seeds → death.
Larva
The second stage in the life cycle of some insects (like mosquitoes) after the egg stage. It is a worm-like creature that lives in water and feeds actively.
e.g. Mosquito larvae are small, worm-like creatures found in stagnant water.
Pupa
The third stage in the life cycle of some insects (like mosquitoes) after the larva stage. It is a non-feeding, resting stage during which the insect transforms into an adult.
e.g. Mosquito pupae are comma-shaped creatures that live in water and come to the surface for air.
Spawn
A cluster of eggs of a frog, often seen as a white jelly-like substance on the surface of water or attached to plants in ponds.
e.g. During the rainy season, you may see spawn in a shallow pond.
Tadpole
The larval stage of a frog that lives in water, has a tail, and breathes through gills. It later develops legs and loses its tail to become an adult frog.
e.g. A tadpole with a tail and no legs is an early stage; a tadpole with hind legs is a later stage.
Froglet
A young frog that has developed legs but still has a small tail and lives both in water and on land. It is the stage between tadpole and adult frog.
e.g. A froglet looks like a tiny frog with a short tail.
Insectivorous plants
Plants that trap and digest insects for nutrition, especially when growing in soil lacking nutrients.
e.g. Drosera (sundew) has saucer-shaped leaves with sticky hairs that trap insects.
Crescograph
A machine invented by Indian scientist Jagadish Chandra Bose to record how plants respond to stimuli like light, heat, electricity, and gravity, and to measure how fast plants grow.
e.g. Bose used the crescograph to show that plants can sense and respond to stimuli.
How It Works
Seed Germination
  1. Step 1: A seed absorbs water, which softens the seed coat.
  2. Step 2: The embryo inside the seed becomes active and starts to grow.
  3. Step 3: The root emerges first and grows downwards into the soil.
  4. Step 4: The shoot emerges and grows upwards towards sunlight.
  5. Step 5: The seedling develops leaves and begins to make its own food.
💡 Most seeds do not require light for germination; they need water and air. Sunlight is needed only after germination for further growth.
Respiration in Humans and Animals
  1. Step 1: We inhale air, which moves from outside to inside our body.
  2. Step 2: Oxygen from the air is used to release energy from food.
  3. Step 3: We exhale air, which moves from inside our body to outside.
  4. Step 4: The number of breaths per minute increases after physical activity like running or dancing.
💡 Breathing is the physical movement of air in and out; respiration is the broader process that includes breathing and energy release.
Life Cycle of a Mosquito
  1. Step 1: Stage I — Egg: Female mosquito lays eggs on or near stagnant water.
  2. Step 2: Stage II — Larva: Eggs hatch into worm-like larvae that live in water and come to the surface for air.
  3. Step 3: Stage III — Pupa: Larvae change into comma-shaped pupae that also live in water and come to the surface for air.
  4. Step 4: Stage IV — Adult: Pupae transform into adult mosquitoes that fly away. Adult females lay eggs, and the cycle repeats.
💡 Kerosene oil sprayed on stagnant water forms a thin layer that prevents larvae and pupae from getting air, causing them to die. This disrupts the life cycle.
Life Cycle of a Frog
  1. Step 1: Stage IA — Spawn: Female frog lays a cluster of eggs (spawn) in water.
  2. Step 2: Stage IB — Embryo: Eggs develop into embryos inside the jelly-like substance.
  3. Step 3: Stage IIA — Tadpole with tail: Embryos hatch into tadpoles that have a tail and no legs, and live in water.
  4. Step 4: Stage IIB — Tadpole with legs: Tadpoles develop hind legs first, then front legs.
  5. Step 5: Stage III — Froglet: The tadpole becomes a froglet with legs and a small tail, living both in water and on land.
  6. Step 6: Stage IV — Adult frog: The tail disappears, legs become strong, and the frog lives both in water and on land.
💡 Tadpoles have tails for swimming; the tail disappears as they become adult frogs. The habitat changes from fully aquatic to semi-terrestrial.
Growth and Movement in Plants (Response to Light and Gravity)
  1. Step 1: When a plant is kept upright, the root grows downwards (towards gravity) and the shoot grows upwards (towards light).
  2. Step 2: When a plant is kept inverted, the root bends and grows downwards, and the shoot bends and grows upwards.
  3. Step 3: When light comes from only one direction, the shoot grows towards the light, while the root continues to grow downwards.
💡 Shoots grow towards light (positive phototropism), roots grow downwards (positive geotropism). This is a response to stimuli.
Life Cycle of a Bean Plant
  1. Step 1: Stage I — Seed: A dry bean seed is planted.
  2. Step 2: Stage II — Seed germination: The seed absorbs water, the seed coat softens, and the embryo starts growing.
  3. Step 3: Stage III — Appearance of leaves: The seedling develops leaves and begins photosynthesis.
  4. Step 4: Stage IV — Appearance of flowers: The mature plant produces flowers.
  5. Step 5: Stage V — Appearance of fruits: Flowers develop into pods (fruits) containing seeds.
  6. Step 6: Death: After producing seeds, the plant gradually dries up and dies.
💡 The life cycle of a plant includes seed, germination, growth, flowering, fruiting, and death. Seeds from the fruit give rise to the next generation.
Exam Traps — Don't Make These Mistakes
⚠ Movement in cars vs. living beings
✗ A car moves, so it is living.
→ Movement alone is not a defining characteristic of living beings. Cars move due to external energy (fuel), but they do not grow, respire, reproduce, excrete, or respond to stimuli on their own.
✓ A car is non-living because it does not show growth, nutrition, respiration, excretion, response to stimuli, or reproduction. Movement in a car is due to an external source of energy, not a life process.
⚠ Plants are non-living because they don't move
✗ Plants are non-living because they do not move from one place to another.
→ Plants do show movement, though not locomotion. They exhibit movements like opening of flowers, growth of shoots towards light, and folding of leaves (touch-me-not). Movement is a characteristic of all living beings, including plants.
✓ Plants are living because they show movement, such as the opening of flowers, growth towards sunlight, and folding of leaves in response to touch. They also grow, respire, excrete, and reproduce.
⚠ Seed is non-living because it does not grow
✗ A seed is non-living because it does not show any characteristics of life.
→ A seed is a living thing in a dormant state. It contains a living embryo that can germinate and grow into a plant when provided with water, air, and suitable conditions. It shows growth and other life processes after germination.
✓ A seed is living because it contains a living embryo. Under suitable conditions (water, air, and appropriate temperature), it germinates and grows into a plant, showing characteristics like growth, respiration, and response to stimuli.
⚠ Breathing and respiration are the same
✗ Breathing and respiration mean the same thing.
→ Breathing is only the physical process of inhaling and exhaling air. Respiration is a broader process that includes breathing and the chemical release of energy from food inside the body.
✓ Breathing is the movement of air in and out of the body (inhalation and exhalation). Respiration is the process that includes breathing and the use of oxygen to release energy from food.
⚠ Excretion only means passing urine
✗ Excretion is only the removal of urine from the body.
→ Excretion includes the removal of all waste products from the body, not just urine. Sweat (water and salts) is also a waste product. Plants excrete excess water and minerals as droplets on leaves.
✓ Excretion is the removal of waste products from the body. In animals, it includes urine and sweat. In plants, it includes excess water and minerals released as droplets on leaves.
⚠ All seeds need light to germinate
✗ Seeds need sunlight to germinate.
→ Most seeds do not require light for germination. They need water and air. Light is required only after germination for the seedling to grow further. Some seeds (like Coleus) need light, while others (like Calendula) need darkness.
✓ Most seeds do not require light for germination. Essential conditions for germination are water and air. Sunlight is needed after germination for the growth of the seedling.
Compare & Contrast
Presence of life characteristics
Living beings
Non-living things
Living beings show all essential characteristics: movement, growth, nutrition, respiration, excretion, response to stimuli, reproduction, and eventual death. Non-living things do not show any of these characteristics.
Number and nature of stages
Life cycle of a mosquito
Life cycle of a frog
A mosquito has four stages: egg, larva, pupa, and adult. A frog has four main stages: egg (spawn), tadpole (with tail then legs), froglet, and adult frog. Both undergo significant changes in body shape and structure, but the mosquito pupa is a resting stage, while the frog tadpole is an active feeding stage.
Direction of growth in response to stimuli
Root growth
Shoot growth
Roots grow downwards towards gravity (positive geotropism) and away from light. Shoots grow upwards towards sunlight (positive phototropism) and away from gravity.
Exam Focus
Marks pattern: 2 MCQs (1 mark each) on characteristics of living vs non-living, 1 SA (3 marks) on seed germination conditions or life cycle of mosquito/frog, 1 LA (5 marks) on comparing life cycles or explaining all characteristics of living beings with examples.
Most asked: Characteristics of living beings (movement, growth, nutrition, respiration, excretion, response to stimuli, reproduction, death) · Conditions required for seed germination (water, air; light not essential for most seeds) · Life cycle of a mosquito (egg, larva, pupa, adult) · Life cycle of a frog (spawn, tadpole, froglet, adult) · Difference between living and non-living · Response to stimuli in plants (touch-me-not, growth towards light)
Don't skip: List and explain any five characteristics of living beings with examples.; Describe the life cycle of a mosquito or a frog with a diagram.; What conditions are essential for seed germination? Describe an activity to show that water and air are necessary for germination.; How do plants respond to stimuli? Give two examples.
One-Line Revision (read aloud before the exam)
  1. Living beings show movement, growth, nutrition, respiration, excretion, response to stimuli, reproduction, and eventually die.
  2. Non-living things do not show any of the essential characteristics of life.
  3. Movement in plants includes opening of flowers, growth towards light, and folding of leaves in touch-me-not.
  4. All living beings need food (nutrition) for growth and development.
  5. Breathing is the physical process of inhaling and exhaling air; respiration is the broader process that releases energy from food.
  6. Excretion is the removal of waste products; in humans it includes urine and sweat; in plants it includes water droplets on leaves.
  7. A stimulus is any event that prompts a living being to respond; a response is the reaction to that stimulus.
  8. Reproduction is necessary for the continuity of life.
  9. A seed is living because it contains an embryo that can germinate under suitable conditions.
  10. Essential conditions for seed germination are water and air; most seeds do not require light for germination.
  11. During germination, the root grows downwards and the shoot grows upwards.
  12. The life cycle of a mosquito has four stages: egg, larva, pupa, and adult.
  13. The life cycle of a frog has four stages: spawn (eggs), tadpole, froglet, and adult frog.
  14. Tadpoles have tails for swimming; the tail disappears as they become adult frogs.
  15. Kerosene oil on stagnant water kills mosquito larvae and pupae by preventing them from getting air.
  16. Plants respond to stimuli; for example, touch-me-not folds its leaves when touched, and shoots grow towards sunlight.
  17. Shoots grow towards light (positive phototropism); roots grow downwards (positive geotropism).
  18. A plant's life cycle includes seed, germination, growth, flowering, fruiting, and death.
  19. Insectivorous plants like Drosera trap insects for nutrition.
  20. Jagadish Chandra Bose invented the crescograph to measure plant growth and response to stimuli.

MCQs — 10 Questions with Answers

Q1. Which of the following is a characteristic of all living beings?

  • A. They can walk from one place to another
  • B. They need food for growth and energy ✓
  • C. They are always green in colour
  • D. They have four legs

Answer: B — All living beings need food for growth and development, whether they are animals or plants.

Q2. What are the tiny pores on plant leaves called through which plants breathe?

  • A. Roots
  • B. Stomata ✓
  • C. Veins
  • D. Flowers

Answer: B — Stomata are tiny pores on the surface of leaves that allow plants to take in and release air for respiration.

Q3. Why is a car NOT considered a living thing even though it moves?

  • A. Because it is made of metal
  • B. Because it does not grow, eat food, breathe, or reproduce ✓
  • C. Because it is too big
  • D. Because it makes noise

Answer: B — Living things must show all characteristics like growth, nutrition, respiration, and reproduction; cars lack these.

Q4. What happens when you touch a touch-me-not (chhui-mui) plant?

  • A. The plant grows taller
  • B. The plant's leaves fold quickly ✓
  • C. The plant changes colour
  • D. The plant produces flowers

Answer: B — Touch-me-not plants respond to the stimulus of touch by folding their leaves as a protective mechanism.

Q5. Which process removes waste products like sweat and urine from a living being's body?

  • A. Respiration
  • B. Excretion ✓
  • C. Reproduction
  • D. Digestion

Answer: B — Excretion is the process by which living beings remove waste products such as sweat and urine from their bodies.

Q6. What is a stimulus in biology? Fill in: A stimulus is anything that causes a living being to ______.

  • A. grow in size
  • B. sleep
  • C. respond or react ✓
  • D. move to another place

Answer: C — A stimulus is defined as anything that causes a living being to respond or react, like touching a hot object.

Q7. If a bird eats seeds and grows bigger, which two characteristics of living beings does this show?

  • A. Movement and reproduction
  • B. Nutrition and growth ✓
  • C. Respiration and excretion
  • D. Response to stimuli and reproduction

Answer: B — Eating seeds shows nutrition (need for food) and becoming bigger shows growth, both key characteristics of living beings.

Q8. Look at the diagram: Which label correctly identifies the part shown? [Imagine a leaf diagram with an arrow pointing to tiny pores]

  • A. Veins
  • B. Stomata ✓
  • C. Chlorophyll
  • D. Epidermis

Answer: B — The diagram shows tiny pores on the leaf surface, which are stomata used for plant respiration.

Q9. Why do plants that are insectivorous (like Drosera) have sticky hairs that trap insects?

  • A. To protect themselves from being eaten
  • B. To get nutrition from insects for growth ✓
  • C. To attract more insects to the plant
  • D. To prevent insects from sleeping on leaves

Answer: B — Insectivorous plants trap insects to get nutrition, showing that plants need food just like animals do.

Q10. What does it mean when we say a living being is dead?

  • A. It has stopped moving
  • B. It cannot show any of the characteristics of living beings even when food, air, and water are available ✓
  • C. It is very old
  • D. It has turned grey in colour

Answer: B — A living being is dead when it cannot show characteristics like movement, growth, respiration, or reproduction even with all resources available.

Flashcards

What is a living being?

A living being is something that shows movement, grows, needs food, breathes, excretes waste, responds to stimuli, and can reproduce.

Name five characteristics that make living things different from non-living things.

Living things show movement, growth, need food for nutrition, respire (breathe), excrete waste, respond to stimuli, and reproduce.

Can plants move?

Yes, plants can move — flowers open and close, touch-me-not leaves fold when touched, and climbing plants wind around objects.

What is respiration?

Respiration is the process of breathing where air moves into the body (inhalation) and moves out of the body (exhalation).

What are stomata and what do they do?

Stomata are tiny pores on the surface of plant leaves that allow plants to take air in and out, helping them breathe.

What is excretion?

Excretion is the removal of waste products from the body, such as sweat, urine, or water droplets on plant leaves.

What is a stimulus and give one example.

A stimulus is anything that prompts a living being to respond; examples include stepping on a thorn or touching a hot cup.

Why is reproduction important for living beings?

Reproduction is important because it creates new living beings and ensures the continuity of life on Earth.

Is a car a living thing? Why or why not?

No, a car is not living because it does not grow, eat food, breathe, excrete, respond to all stimuli, or reproduce.

How do you know a shell found on the beach could contain a living snail?

The shell is part of the snail's body, so a living snail could be inside even if the shell is not moving.

Important Board Questions

Is a shell found on the beach a living thing or non-living thing? Give one reason. [1 mark]

A shell is part of a snail's body. Even if it is not moving, it could contain a living snail inside. A living being can be inside non-moving structures.

Name any two characteristics that prove a dog is a living being but a toy dog is not. [2 marks]

Think about: Does it eat food? Does it grow? Does it breathe? Does it move on its own? Does it have young ones? A real dog does all these; a toy dog does none.

How do plants respond to stimuli? Give two examples from your everyday life. [3 marks]

Plants show response to touch (touch-me-not leaves fold) and to light (flowers open in day, close at night). Explain what stimulus causes each response and what the plant does.

Explain why respiration and excretion are important for living beings. Draw and label a diagram showing how air enters and leaves a human body during respiration. [5 marks]

Respiration provides oxygen for life; excretion removes harmful waste. Diagram must show: nose/mouth → lungs → carbon dioxide out. Label: inhale (air in), exhale (air out), lungs. Explain that all living beings respire.

True or False: A car is a living thing because it moves. Give one reason for your answer. [2 marks]

False. A car may move, but it does not grow, eat food, breathe, respond to all stimuli, or reproduce. Movement alone does not make something living.

Assertion-Reason Questions for Living Creatures: Exploring their Characteristics

Q1. Assertion (A):

Plants are living beings because they show movement.

Reason (R):

Plants fold their leaves in response to touch and sunset, and climbing plants wind around objects.

Answer: A — Both A and R are true, and R is the correct explanation of A — Both statements are true, and the reason correctly explains why plants are living—they do show movement even though they don't walk from place to place. This movement in response to stimuli proves they are alive.

Q2. Assertion (A):

A car is a non-living thing even though it can move on roads.

Reason (R):

Living beings show growth, reproduction, respiration, and response to stimuli, but a car does not.

Answer: A — Both A and R are true, and R is the correct explanation of A — Both the assertion and reason are true. Just because something moves doesn't make it alive. A car lacks all the other characteristics of living beings, so it is non-living. This reason correctly explains why movement alone is not enough.

Q3. Assertion (A):

Excretion is the removal of waste products from living beings.

Reason (R):

Animals excrete urine and sweat, while plants also excrete water and minerals through leaves.

Answer: B — Both A and R are true, but R is NOT the correct explanation of A — The assertion is true—excretion is waste removal. The reason is also true—animals and plants do excrete these substances. However, the reason is not the complete explanation of what excretion is; it's just giving examples. A better reason would explain what excretion means.

Unlock more Assertion-Reason questions in Premium — unlock →

Case-Based Questions (CBQ) for Living Creatures: Exploring their Characteristics

Case Study:

Priya visits her grandmother's garden early in the morning. She notices water droplets on the grass and rose plants. Later, she sees a butterfly touch the touch-me-not plant's leaves, and the leaves immediately fold up. She also observes a small puppy running around the garden and a young mango tree growing in the corner. Her grandmother explains that everything in the garden—the plants, animals, and even the puppy—are all living beings.

Q1. What does the water droplet on the grass leaves indicate about plants?

  • A. Plants are drinking water from the ground
  • B. Plants are excreting excess water and minerals ✓
  • C. It rained during the night
  • D. The gardener watered the plants

Answer: B

Q2. When the butterfly touched the touch-me-not leaves and they folded, which characteristic of living beings was shown?

  • A. Reproduction
  • B. Growth
  • C. Response to stimulus ✓
  • D. Respiration

Answer: C

Q3. Why is the young mango tree in the garden considered a living being?

  • A. Because it is very big
  • B. Because it grows, respires, reproduces, and responds to its surroundings ✓
  • C. Because it has green colour
  • D. Because it is planted by humans

Answer: B

Unlock more case studies in Premium — unlock →

Next chapterNature's Treasures →
Found this useful? Share it with your class group.

You've seen the free preview. Open the full interactive study kit — mind map, instant-graded quiz, progress tracking — free, no sign-in required.

Open Full Study Kit — Free →

Premium unlocks the full Question Bank, Daily Practice Papers, Chapter Quiz and Full Mock Papers for every chapter.