NCERT Solutions for Class 6 Science Chapter 10 Living Creatures Exploring Their Characteristics (PDF) – 2027

— the five things named in the book and two more from my classroom, with my guess in column II:

The reason must name a characteristic — not just say “it looks alive”.

Because the pigeon shows every characteristic of life and the pencil shows none of them. Compare them side by side.

Differences between living beings and non-living things:

Take the living things from your list — the pigeon, the plant, the house lizard, your classmates — and look for what they have in common. Every one of them:

• shows some movement, of the whole body or of a part;
• needs food, water and air to stay alive;
• grows from a small young one into an adult;
• respires;
• gets rid of waste from the body;
• responds to a change in the surroundings — light, touch, heat, sound;
• reproduces, so its kind continues;
• dies after a certain span of life.

No, a car is not living. It moves, but movement alone does not make a thing alive — and a car cannot move until a driver turns the key.

Tasks you can do but a car cannot:

The characteristics that make me different from a car are growth, nutrition (food), respiration, excretion, response to stimuli, reproduction and death.

Does “a car does not grow” alone prove it is non-living? No — a grown-up adult also stops growing. I call the car non-living because it shows none of these characteristics: it did not grow from a small car, takes no food (petrol is only fuel), does not respire or excrete, does not respond on its own, cannot reproduce and does not die.

Living beings move, need food (nutrition), grow, respire, excrete, respond to stimuli, reproduce and finally die. Non-living things do not show these characteristics.

Yes, movement is one characteristic — but it can never be used alone.

Five things around me that move on their own:

1. A street dog running across the road
2. An ant in a line on the kitchen shelf
3. A ceiling fan (once the switch is on)
4. A river or a stream of rainwater in the drain
5. A clock’s second hand (or a wind-up toy car)

Are all five living? No — only two.

Yes, plants are living. They do not move from place to place, but they do show movement — flowers open, the hairs of Drosera move inward to trap an insect, and climbers wind around a support. Plants also grow, need food, respire, excrete, respond to stimuli, reproduce and die.

— how some insectivorous plants trap insects:

No. The dress will be far too short and too tight now.

The reason is growth. In four years my arms and legs have become longer, my shoulders wider and my whole body heavier. This increase in size did not come from outside — my body built the new parts itself, from the food I ate.

Yes. Growth is one of the characteristics of living beings — every living thing grows at some stage of its life.

• A gram seed on wet cotton becomes a seedling in three days and a plant with several leaves in three weeks.
• A mango sapling planted in the courtyard becomes a tree taller than the house.
• A calf becomes a cow; a tadpole becomes a frog.

Every living being needs food. Five from around an Indian home:

The process is respiration (breathing is a part of it). Sample answer — my breaths per minute (breathing in and out once = one breath):

Yes, there is a clear difference. The harder the activity, the more breaths per minute — and each breath is deeper too.

Yes. When a dog, cat, cow or buffalo is resting, its chest and abdomen rise as it breathes in and fall as it breathes out, again and again. After running, a dog pants fast with its tongue out. This movement shows that these animals are breathing.

Yes — all living beings respire, and plants are no exception.

How a plant does it: there are tiny pores called stomata on the surface of the leaves. These pores let air move in and out of the plant. Roots take in the air present in the spaces between soil particles, and woody stems have tiny openings of their own.

Yes — and those patches are proof of excretion.

The patches are formed by sweat. Sweat consists of water and salts removed by the body as waste products. When the water dries off in the summer heat, the salt is left behind on the cloth as a whitish ring.

• In animals, urine is also formed as a product of excretion.
• The waste air we breathe out is removed too.

Yes, plants also excrete.

Plants excrete excess water and minerals in the form of small droplets on the leaves — you can notice this on grasses and roses. Look at a lawn just after sunrise: tiny beads of water sit along the tip and edges of every blade of grass.

I pull my foot (or my hand) away at once, before I have even thought about it — and I usually cry out.

Yes, plants also respond to stimuli. The book gives two clear examples.

• Touch-me-not (mimosa, chhui-mui, lajjalu) — the leaves fold up the moment you touch them, and open again after some minutes.
• Sleeping leaves — the leaves of certain plants facing each other tend to come together after sunset. This is seen in the amla (Indian gooseberry) tree.

Other plants in an Indian neighbourhood whose leaves fold after sunset:

They respond to different stimuli. The leaves of chhui-mui fold up as soon as they are touched — the stimulus is touch. The leaflets of amla come together at sunset, when it becomes dark, and open again in the morning — the stimulus is the change in light (darkness). Responding to such changes is a characteristic of living beings.

Yes, I have seen young ones of animals — and no, non-living things never have young ones.

Non-living things: a pencil has never produced a small pencil, a chair has never produced a stool and a bulb has never produced a little bulb. New pencils, chairs and bulbs are all made in a factory by people — they are not born from an older one.

Reproduction is necessary for the continuity of life. Every living being dies after some time. By producing new ones of its own kind, it makes sure that its kind does not disappear but continues, generation after generation.

Now use the eight characteristics as a checklist. Here is the completed Table 10.1.

A seed is living. It looks lifeless, but inside its seed coat there is a tiny living embryo. When it gets water and air, the seed germinates, grows into a plant, and that plant produces new seeds. A dead (roasted) seed never germinates, however much water and air it gets.

Yes — soaked moong and chana sprout in a day or two. I think a seed needs water, air and a suitable (warm) temperature to germinate; I am not sure whether it needs sunlight.

How to investigate: sow the same kind of seeds in identical pots. Keep one pot with all the conditions, and in each of the other pots take away or change just one condition — no water, too much water, no light. Then watch which pots show germination. Activity 10.2 does exactly this.

Availability of air, sunlight and water (Table 10.2). In Pot B the water standing above the soil fills the spaces between soil particles, so the seeds get no air.

Here is Table 10.2 completed after 7 to 10 days.

No — sunlight is not necessary for the germination of bean seeds.

The evidence: Pot C was kept in complete darkness with moist soil, and the seeds in it germinated. Only water and air were available, and that was enough.

No, no pot except D received all three in the right amounts.

• Pot A — air and sunlight, but no water.
• Pot B — sunlight and plenty of water, but no air.
• Pot C — air and water, but no sunlight.
• Pot D — air, water and sunlight, all in the right amount.

Yes — Pot B. Water is kept standing above the soil, so it fills all the spaces between the soil particles and pushes out the air that the seeds need.

They do not germinate. They swell up, become soft, turn dark, start to rot and give off a bad smell.

The seeds in Pot C and Pot D receive both air and water.

Germination is seen in Pots C and D — exactly the two pots that got both air and water. That is the answer the experiment was designed to produce.

Conditions that favour germination: the right amount of water, enough air, and a suitable (warm) temperature. Sunlight is not essential.

In the book’s own words: germination of bean seeds requires the right amount of water and air.

Each condition does a specific job, so yes — if even one is missing, germination is affected or stops altogether.

Besides water, air and light, several other conditions decide whether a seed will sprout.

Why plants were placed among living beings in Activity 10.1: they grow, they need water, air and nutrients, they respire through stomata, they excrete droplets on their leaves, they respond to stimuli such as touch and light, they reproduce through seeds, and they finally die.

Do plants show growth in Activity 10.2? Yes, very clearly.

Other characteristics these plants show: they take food (first the food stored in the seed, then food made in their leaves), they respire (the seeds in Pot B, without air, died), and they respond to stimuli (the root grows down and the shoot grows up).

Living — and now I can prove it instead of only saying it.

Plants respond to sunlight by growing towards it — and yes, sunlight does affect the direction of growth, but only of the shoot.

• A shoot bends and grows towards the light. Keep a money plant beside a window for a fortnight and all its leaves face the window.
• A root does not follow the light at all. It keeps growing downwards, into the soil where the water and minerals are.

Prediction: even if the plant is placed upside down, its root will bend and grow downwards and its shoot will bend and grow upwards.

Activity design: germinate bean seeds until each has a small root and shoot. Tie three seedlings on wet blotting paper and stand them in three beakers: A upright, light from all sides; B inverted (upside down), light from all sides; C upright, light from one side only (through a hole in a box). Predict, then observe for a few days and record the direction in which the root and shoot grow.

Here is Table 10.3 completed. Fill your predictions before you set the beakers aside, and the observations after 4 to 7 days.

Observations:

1. A (upright): the root grows downwards and the shoot grows upwards.
2. B (inverted): the root bends and grows downwards; the shoot bends and grows upwards.
3. C (light from one side): the shoot bends towards the light; the root keeps growing downwards.

Predictions: A and C usually match. For B, many of us predict that the inverted seedling will keep growing the wrong way — it does not.

Sample observations for a bean plant (your dates will differ). The first change — the seed swelling and a small root coming out — is seen in about 3 to 4 days.

For a bean plant, the first flower usually appears about 40 to 55 days after sowing — roughly six to eight weeks. Write the exact number of days your plant took.

Yes — growth continues even after the flower dries. Watch one flower carefully and do not pluck it.

Yes — a pod with seeds (the fruit of the bean plant) develops from the flower.

The plant slowly stops growing, turns yellow, dries up and dies — even though you keep watering it.

• Leaves lose their green colour and become yellow, then brown and papery.
• New leaves and flowers stop appearing.
• The stem becomes dry and brittle; the pods rattle when shaken.
• Finally all the activities of life come to an end and the plant is considered dead.

Yes — the plant becomes yellow and dries up in spite of regular watering. Water alone cannot keep a plant alive once it has finished its life cycle.

Then sow the seeds from your own pods. In about a week they germinate and the whole story starts again. That completes the circle and shows you what a life cycle means.

Yes. Some young ones look like small copies of their parents; others look completely different. Draw them and write both names.

Yes — there is a direct relation. Mosquitoes need stagnant water to breed, so stagnant water anywhere near a house means mosquitoes in the house.

The female mosquito lays her eggs on or near stagnant water, and the larvae and pupae can live only in water. Female mosquitoes spread diseases such as malaria, dengue and chikungunya, so we must not let water collect anywhere around us.

Both wriggle in the water, but a hand lens shows they are quite different.

They come up to breathe.

Mosquito larvae and pupae live in water but require air to respire. They cannot take in the air dissolved in the water the way a fish does, so they must move to the surface of the water for air. Each has a short breathing tube which it pokes just above the water film before sinking again.

Break the cycle at any one stage and no adult mosquito is produced. The easiest stages to attack are the ones that live in water.

To kill the mosquito larvae and pupae growing in that water. The book gives the reason in one clear sentence.

Separate the two kinds of creature and watch which one turns into the other. Whatever changes into the other must come first.

Here is the plan, following Avadhi’s design in the book:

What you will actually find: container L shows larvae turning into pupae after a few days; container P shows adult mosquitoes emerging first. So the sequence is

Now you must get the answer by counting instead of separating.

1. Count on Day 1. With a hand lens, count how many larvae and how many pupae are in the container. Write both numbers down.
2. Change nothing else. Keep the container covered with a fine cloth, in the same place, and do not add or remove any creature.
3. Count again every day for a week, at the same time each day, and record the two numbers plus the number of adult mosquitoes that have emerged.
4. Read the trend.

No — it is very hard to imagine, and that is exactly why the life cycle of a mosquito is worth studying.

How to decide the sequence: arrange the stages by how much of the frog’s body has been built — start with the one that has no body parts at all and end with the one that has them all.

Here is Table 10.5 completed, reading Fig. 10.7 from the printed page.

Draw it as a circle, because the adult frog lays the eggs that start the cycle again. Some stages of Fig. 10.7 are clubbed together — for example, A and F are both put under Stage I.

The four stages, in the book’s words:

1. the egg stage, which progresses to the embryo stage;
2. the tadpole stage — an early stage with a tail and no legs, and a later stage with hind legs;
3. the froglet stage;
4. the adult frog stage.

Frog eggs have no hard shell. They are tiny, and hundreds of them are laid together in water, held in a soft, white, jelly-like cluster called spawn that floats near the edge of a pond. A hen’s egg is large, has a hard shell and is laid on land, one at a time.

The egg (spawn) stage is the shortest. In Fig. 10.8 the spawn (Day 1) has already become an embryo by Day 3–4:

Yes — and this is one of the most striking things about a frog. It begins life entirely in water and ends up able to live both in water and on land.

Every feature at every stage is there for a reason. Match them up.

Birds do change, but nothing like as dramatically as a mosquito or a frog.

How this differs from a frog or a mosquito:

• A chick already has the same body plan as its parent — a beak, two wings, two legs. It mainly grows bigger and grows feathers.
• Its habitat does not change — nest, then trees and air.
• There is no resting stage like a pupa and no organ is lost the way a tadpole loses its tail.

Both are life cycles — both start small, grow, produce the next generation and end in death. But the details differ.

Similarities

• Both begin from a single small starting point — a seed in a plant, an egg or a newborn in an animal.
• Both pass through several definite stages in a fixed order.
• Both grow and develop, needing food, water and air throughout.
• Both reach a stage where they can reproduce and produce the next generation.
• Both finally die, while the kind continues through the next generation.
• In both, the cycle then repeats — seeds give new plants; eggs give new animals.

Differences

Take each row separately. Three of them have examples; one of them does not — and saying why is the real answer.

Keep away from the stored grain exactly the things a seed needs to germinate — water, air and warmth. Grains and pulses are seeds; if they germinate or grow mould in the store, they are spoilt.

The tail helps the tadpole to swim. A tadpole lives only in water and has no legs in its early stage, so its tail is its only way of moving. With the tail it can swim about to find food and quickly escape from fish and other enemies.

The wooden log is non-living.

Charan is right that it is non-living, but his reason is wrong. Not moving does not make a thing non-living — a tree never moves from its place and is living, while a car moves and is non-living.

Charu is wrong. Being made from a tree does not make the log living. The log does not grow, take food, respire, excrete, respond to stimuli or reproduce, so it is non-living.

Similarities

• Both pass through four stages.
• Both begin life as an egg laid on or near water.
• In both, the young ones live in water and the adult can leave it.
• Both show significant changes in appearance, body shape and structure between stages, and a change of habitat.
• In both, the young one looks completely unlike the adult.
• Both end with an adult that reproduces, so the cycle continues.

Distinguishing features

After one week: the shoot will have bent and grown upwards, and the root will have bent and grown downwards, even though the pot is still lying on its side.

Reasons: shoots of plants grow upwards and towards sunlight, while roots grow downwards into the soil. Activity 10.3 showed the same thing — in the inverted seedling (beaker B) the root bent down and the shoot bent up.

What they want to find out: whether the direction in which a seed is sown decides the direction in which its root and shoot grow — or whether the root always grows downwards and the shoot always upwards, no matter how the seed is placed.

How they will know if they are correct: after about a week they look at the seedlings through the containers. If in all three the root has bent downwards and the shoot upwards, then the way a seed is placed does not change the direction of growth — roots always grow down and shoots always grow up.

Aim: to find out whether temperature affects seed germination.

Method:

1. Put 10 similar bean seeds on wet cotton in each of four identical bowls.
2. Keep the bowls at different temperatures: in a refrigerator, in a cool corner, at room temperature, and in a hot place (such as a closed glass jar in the sun).
3. Keep everything else the same — the kind of seeds, the water and the light.
4. After a week, count the seeds that have germinated in each bowl.

Result: most seeds germinate at room temperature and few or none in the refrigerator or the very hot bowl. So temperature does affect seed germination.

— from a talk with the gardener: each plant needs the right amount of water, sunlight and manure, and different plants take different times to germinate and flower.

Yes. Many plants can be grown from a part of a plant — a piece of stem, a leaf, a root or an underground stem — instead of from a seed. For example: rose and money plant (stem cutting), Bryophyllum (leaf), potato and ginger (underground stem), sweet potato (root).

— the summary page of my picture book (days after sowing; your plants may differ):

Yes — the stages are exactly the same four, though they are passed on land instead of in water.

Where they differ: the butterfly’s larva and pupa live on land, on a plant; the mosquito’s live in water. A butterfly’s whole cycle takes about a month, a mosquito’s only a week or two.

Yes, very strongly. The same insect completes its cycle much faster in one season than in another, and may not complete it at all in a bad year.

(continuing the poem):