Class 9 ( science)

 

Link to see notes and extra questions of Following chapters

Class 9 Tissue

Class 8 ( notes + Extra questions)

 Chapter 3 Health : The Ultimate treasure

Chapter 6 Pressure , Winds , Storms and Cyclone

class 7 exploring society and beyond ( notes and extra questions)

 Class 7 ch 7 The Gupta Era

Class 7 Curiosity (Notes and Questions)

Chapter 12  Earth ,Moon and the Sun

Chapter 4  The world of metal and non metal

Preposition worksheet

 

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📘 PREPOSITIONS WORKSHEET

A. Choose the correct preposition.

1. The cat is hiding ___ the table.

a) on
b) under
c) over

2. We will meet ___ Monday.

a) on
b) in
c) at

3. The boys are running ___ the playground.

a) across
b) between
c) for

4. My birthday is ___ December.

a) in
b) on
c) at

5. She kept her bag ___ the chair.

a) on
b) into
c) through

6. The train passed ___ the tunnel.

a) at
b) through
c) to

7. The picture is hanging ___ the wall.

a) in
b) on
c) behind

8. Riya is sitting ___ her two best friends.

a) among
b) between
c) across

9. The children went ___ the park.

a) to
b) on
c) at

10. The dog jumped ___ the bed.

a) onto
b) between
c) from

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B. Fill in the blanks by choosing the correct preposition.

11. He was born ___ 2012.

a) on
b) in
c) at

12. The birds flew ___ the sky.

a) under
b) over
c) behind

13. She walked ___ the road carefully.

a) across
b) behind
c) into

14. The students were standing ___ the classroom.

a) at
b) in
c) over

15. The ball rolled ___ the hill.

a) down
b) across
c) into

16. He came ___ Jaipur yesterday.

a) from
b) between
c) with

17. We rested ___ the shade of a tree.

a) under
b) across
c) into

18. The teacher is standing ___ the blackboard.

a) in front of
b) between
c) among

19. She goes to school ___ bus.

a) by
b) with
c) from

20. The cat jumped ___ the box.

a) into
b) with
c) across

 

Preposition Rules

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📘 Preposition Rules with Examples

Rule No.	Rule	Explanation	Examples
1	Prepositions show relationship	They show relation of a noun/pronoun to another word.	The book is on the table.
2	Prepositions come before a noun/pronoun	A preposition is always followed by a noun/pronoun.	She sat beside him.
3	Preposition of Time – at	Used for exact time.	School starts at 8 am.
4	Preposition of Time – on	Used for days and dates.	The test is on Monday.
5	Preposition of Time – in	Used for months, years, seasons, long periods.	We travel in December.
6	Preposition of Place – in	Used for large areas/closed spaces.	She lives in Delhi.
7	Preposition of Place – on	Used for surfaces or floors.	The cup is on the shelf.
8	Preposition of Place – at	Used for specific places or points.	I am at the bus stop.
9	Preposition for Movement – to	Shows direction to a specific place.	She is going to school.
10	Movement – into	Shows entering.	The cat jumped into the box.
11	Movement – onto	Shows movement to a surface.	The boy climbed onto the roof.
12	Preposition with	Shows use or possession.	She wrote with a pen.
13	Preposition by	Shows method, transport, proximity.	We travel by bus.
14	Preposition for	Shows purpose, duration.	This gift is for you.
15	Preposition from	Shows starting point.	He came from Jaipur.
16	Preposition between	Used for two people/things.	Share this between Riya and Sam.
17	Preposition among	Used for more than two.	She was standing among friends.
18	Preposition over	Shows movement above or covering.	The plane flew over the city.
19	Preposition under	Shows lower position.	The puppy is under the table.
20	Preposition before	Earlier than something.	Come before 9 am.
21	Preposition after	Later than something.	We played after lunch.
22	Preposition behind	At the back of something.	The school is behind the park.
23	Preposition near	Close to something.	My house is near the market.
24	Preposition across	From one side to another.	He swam across the river.
25	Preposition through	Going inside and out.	The train passed through the tunnel.
26	Preposition up	Indicates upward direction.	Climb up the stairs.
27	Preposition down	Indicates downward direction.	The ball rolled down the hill.
28	Preposition during	Shows the time something happens.	We study during the evening.
29	Preposition about	Refers to a topic.	We talked about the exam.
30	Preposition without	Shows absence of something.	She left without her bag.

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Class 6 living creatures Curiosity

🌿 CHAPTER 10 – LIVING CREATURES: EXPLORING THEIR CHARACTERISTICS

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⭐ FULL CHAPTER EXPLANATION

1. Living & Non-Living Things

The world around us has living and non-living things.
To classify them, we compare everything with ourselves.

Living things

They have all the following characteristics:

1. Movement

2. Growth

3. Need for food (nutrition)

4. Respiration (breathing)

5. Excretion (removal of wastes)

6. Response to stimuli

7. Reproduction

8. Death

Non-living things

They do not show these characteristics.

Example:

• A pigeon is living because it moves, grows, breathes, and reproduces.

• A pencil does not grow or breathe → non-living.

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⭐ CHARACTERISTICS OF LIVING BEINGS (Detailed Explanation)

1. Movement

• Animals move from place to place.

• Plants do not move from place to place, but they show movements:

  • Flower opening

  • Leaves of Drosera closing when insects touch them

  • Touch-me-not leaves fold when touched

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2. Growth

• All living things grow.

• A child becomes taller over the years.

• Plants also grow from seeds into big plants.

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3. Nutrition

• Living things need food for:

  • Energy

  • Growth

  • Repair

• Plants make their own food.

• Animals depend on plants or other animals.

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4. Respiration

• Inhaling and exhaling are parts of respiration.

• Humans breathe through lungs.

• Fish use gills.

• Plants breathe using stomata (tiny pores on leaves).

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5. Excretion

All living beings remove waste:

• Humans excrete sweat and urine.

• Plants excrete through:

  • Droplets on leaves

  • Shedding yellow leaves

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6. Response to Stimuli

A stimulus is something that causes a reaction.

Examples:

• Touching a hot cup (stimulus) → quickly pulling your hand away (response)

• Touch-me-not plant folds leaves when touched

• Some plants close leaves at sunset

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7. Reproduction

Living beings produce young ones of their own kind.
Examples:

• Cats → kittens

• Dogs → puppies

• Plants → seeds → new plants

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8. Death

Every living being eventually dies, even if food, water, and air are available.

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🌱 SEEDS & GERMINATION

Essential Conditions for Germination

A seed needs:

1. Water – softens seed coat

2. Air – for respiration

3. Right temperature

4. Light is NOT necessary for germination in most seeds

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🌱 Growth & Movement in Plants

Roots and shoots show special movements:

• Shoot grows upward—towards sunlight

• Root grows downward—towards gravity

Even if a seedling is placed upside down:

• Root bends downward

• Shoot bends upward

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🌿 Life Cycle of a Plant

Stages:

1. Seed

2. Germination

3. Seedling

4. Growing Plant

5. Flower

6. Fruit with seeds

7. Death of plant

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🦟 Life Cycle of Mosquito

4 stages:

1. Egg

2. Larva

3. Pupa

4. Adult

Mosquitoes lay eggs on stagnant water.
Larvae and pupae breathe air → come to water surface.

Kerosene prevents breathing → kills larvae and pupae.

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🐸 Life Cycle of Frog

Stages:

1. Egg (spawn)

2. Embryo

3. Tadpole (with tail)

4. Tadpole with legs

5. Froglet

6. Adult frog

Below is a clear, simple, Class-6 level detailed explanation of life cycles, covering plants, mosquitoes, and frogs exactly as taught in your Chapter 10.
This is a final, complete, long explanation — easy to understand and full of examples.

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🌱 LIFE CYCLES – COMPLETE DETAILED EXPLANATION

A life cycle is the series of changes that a living being goes through from birth to adulthood, and finally till it dies.
Every living thing has a life cycle, but the stages are different for plants, insects, birds, and animals.

Life cycles show:

• How a living being grows

• How it changes shape

• How it reproduces

• How the next generation begins

Let us understand the three major life cycles taught in your chapter.

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🌿 1. LIFE CYCLE OF A PLANT (Bean Plant Example)

The bean plant goes through several stages from seed → adult plant → seed again.
This is a circular, never-ending process.

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⭐ Stage 1: Seed

• The life of a plant begins with a seed.

• A seed has:

  • Seed coat (protective layer)

  • Embryo (baby plant)

  • Stored food

Seeds look dry and inactive, but they are living.

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⭐ Stage 2: Seed Germination

Germination begins when the seed gets:

1. Water – softens the coat

2. Air – needed for respiration

3. Right temperature

What happens during germination?

• The seed coat breaks.

• The root (radicle) comes out first and grows downward.

• Then the shoot (plumule) grows upward.

• A small seedling forms.

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⭐ Stage 3: Seedling

A seedling has:

• Tiny green leaves

• A thin stem

• A small root system

It starts making its own food using sunlight (photosynthesis).

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⭐ Stage 4: Growing Plant

The plant becomes bigger:

• More leaves appear

• Stem becomes stronger

• Roots grow deeper

Now the plant is ready to produce flowers.

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⭐ Stage 5: Flowering

Flowers are the reproductive organs of plants.
Inside the flower, pollination happens, and seeds begin to form.

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⭐ Stage 6: Fruit Formation

After pollination:

• Flower dries

• Fruit forms

• Fruit contains seeds

In bean plants, the fruit is a pod.

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⭐ Stage 7: Death of Plant

Once the plant completes:

• flowering

• fruiting

• seed production

…it becomes yellow, dries up, and dies, even if water is provided.

Seeds from the pod can start the cycle again.

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🔁 Summary of Plant Life Cycle

Seed → Germination → Seedling → Plant → Flower → Fruit → Seed → (cycle repeats)

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🦟 2. LIFE CYCLE OF A MOSQUITO

Mosquitoes undergo complete metamorphosis, meaning the body shape changes totally at each stage.

There are 4 stages:

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⭐ Stage 1: Eggs

• Female mosquitoes lay eggs on or near stagnant water.

• They float on the water surface in clusters called rafts.

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⭐ Stage 2: Larva

• Eggs hatch into larvae ("wrigglers").

• They look like small, thin worms.

• They swim actively in water.

• They come to the surface to breathe through a tube.

They feed a lot and grow quickly.

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⭐ Stage 3: Pupa

• Larvae turn into pupae, which look like commas (“ , ” shape).

• Pupae do NOT feed.

• They float on water surface and move in a curved motion.

• Inside, big changes happen — they are transforming into adults.

This is like a resting and changing stage.

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⭐ Stage 4: Adult Mosquito

• The pupa splits open.

• A fully developed adult mosquito comes out.

• It rests for some time on the water surface.

• Then it flies away.

Female mosquitoes then lay eggs, and the life cycle restarts.

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🔁 Summary of Mosquito Life Cycle

Egg → Larva → Pupa → Adult → (cycle repeats)

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🐸 3. LIFE CYCLE OF A FROG

Frogs undergo metamorphosis, changing their body from water-living to land-and-water-living.

They have 6 stages:

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⭐ Stage 1: Spawn (Eggs)

• Frogs lay eggs in clusters called spawn.

• Eggs are covered with a jelly-like layer which protects them.

• Found in water bodies like ponds.

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⭐ Stage 2: Embryo

• Inside each egg, an embryo develops.

• The embryo grows and prepares to hatch.

• Looks like a small black dot inside the jelly.

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⭐ Stage 3: Tadpole (With Tail)

• The egg hatches into a tadpole.

• It has:

  • A long tail

  • gills for breathing

  • No legs

Tadpoles swim like fish and eat plant material.

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⭐ Stage 4: Tadpole with Legs

Gradually:

• Hind legs appear

• Then front legs also appear

• Body shape starts changing

• Lungs begin to form

• Tail becomes shorter

Now it begins spending some time on land.

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⭐ Stage 5: Froglet

• Tail is very small

• Legs are fully developed

• Looks like a tiny frog

• Breathes through lungs

• Can hop and swim

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⭐ Stage 6: Adult Frog

• Tail disappears completely

• Fully developed adult

• Lives both on land and in water

• Adult frogs lay eggs, and the cycle repeats

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🔁 Summary of Frog Life Cycle

Spawn → Embryo → Tadpole → Tadpole with legs → Froglet → Adult → (cycle continues)

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⭐ WHY ARE LIFE CYCLES IMPORTANT?

Life cycles help living beings to:

• Grow

• Change into adult forms

• Reproduce

• Continue their species

Without life cycles, living beings cannot survive on Earth.

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📘 IMPORTANT DEFINITIONS

Term	Definition	Example
Living beings	Things that show all characteristics of life	Humans, animals, plants
Non-living things	Things that do not show life processes	Stone, book
Stimulus	Anything that causes a reaction	Touch, light
Response	Reaction to stimulus	Hand withdrawal
Excretion	Removal of wastes	Urine, sweat
Germination	Growth of seed into seedling	Bean germination
Life cycle	Different stages from birth to death	Frog life cycle
Larva	Early form of insect	Mosquito larva
Pupa	Stage before adult	Mosquito pupa
Froglet	Young frog with tail	Frog stage

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📝 20 MULTIPLE CHOICE QUESTIONS (MCQs) WITH ANSWERS

1. Which of the following is a stimulus?
   a) Walking
   b) Touch
   c) Eating
   d) Running
   Ans: b

2. Which of these shows growth?
   a) Stone
   b) Table
   c) Cat
   d) Pen
   Ans: c

3. Plants breathe through—
   a) Lungs
   b) Skin
   c) Stomata
   d) Leaves only
   Ans: c

4. Removal of waste is called—
   a) Respiration
   b) Digestion
   c) Excretion
   d) Growth
   Ans: c

5. Touch-me-not responds to—
   a) Light
   b) Sound
   c) Touch
   d) Water
   Ans: c

6. Which condition is NOT needed for germination?
   a) Water
   b) Air
   c) Sunlight
   d) Right temperature
   Ans: c

7. Mosquito lays eggs in—
   a) Dry soil
   b) Stagnant water
   c) Sand
   d) Plants
   Ans: b

8. Frog eggs are called—
   a) Spawn
   b) Larva
   c) Tadpole
   d) Pupa
   Ans: a

9. Tadpole breathes using—
   a) Gills
   b) Lungs
   c) Skin
   d) Stomata
   Ans: a

10. Example of excretion in plants—
    a) Flowering
    b) Fruit formation
    c) Water droplets
    d) Leaf growth
    Ans: c

11. Movement in plants—
    a) Walking
    b) Opening of flowers
    c) Running
    d) Jumping
    Ans: b

12. Roots grow—
    a) Upward
    b) Sideways
    c) Downward
    d) Randomly
    Ans: c

13. The young one of a frog is—
    a) Froglet
    b) Pupa
    c) Caterpillar
    d) Cub
    Ans: a

14. Seeds need ______ for germination.
    a) Air & Water
    b) Food & Light
    c) Soil only
    d) Heat only
    Ans: a

15. Non-living thing—
    a) Cat
    b) Tree
    c) Car
    d) Human
    Ans: c

16. Plants respond to—
    a) Music
    b) Light
    c) Wind
    d) All
    Ans: d

17. Frog tail disappears in—
    a) Tadpole stage
    b) Froglet stage
    c) Adult stage
    d) Egg stage
    Ans: b

18. Respiration gives—
    a) Energy
    b) Colour
    c) Water
    d) Food
    Ans: a

19. Example of reproduction—
    a) Eating
    b) Growing
    c) Giving birth
    d) Sleeping
    Ans: c

20. Growth in humans is—
    a) Reversible
    b) Slow
    c) Fast
    d) Permanent increase in size
    Ans: d

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✨ 20 VERY SHORT QUESTIONS (1–2 lines) WITH ANSWERS

1. What is a stimulus?
   Anything that causes a reaction.

2. What is excretion?
   Removal of waste products.

3. Name breathing pores in plants.
   Stomata.

4. What do seeds need to germinate?
   Air, water, right temperature.

5. Name one insectivorous plant.
   Drosera.

6. Which living being lays eggs on water?
   Mosquito.

7. What is the young frog called?
   Froglet.

8. What is the first stage of frog life cycle?
   Spawn.

9. Which gas is needed for respiration?
   Oxygen.

10. Name one plant movement.
    Flower opening.

11. What is reproduction?
    Producing young ones.

12. Which part grows downward?
    Root.

13. What is germination?
    Seed → seedling.

14. Name a process plants use to remove water.
    Transpiration.

15. What is a larva?
    Early stage of mosquito.

16. Give an example of a non-living thing.
    Stone.

17. Who breathes through lungs?
    Humans.

18. What helps tadpoles swim?
    Tail.

19. What is life cycle?
    Stages from birth to death.

20. Name one waste product of humans.
    Urine.

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✨ 10 SHORT QUESTIONS (40–50 words) WITH ANSWERS

1. Why are plants considered living if they cannot move?

Plants show many life processes such as growth, respiration, excretion, response to stimuli, and reproduction. They may not move from place to place like animals, but they show movements such as opening of flowers, bending towards light, and closing of leaves.

2. Explain why seeds need water to germinate.

Water softens the seed coat and activates the embryo inside the seed. It helps in chemical processes that lead to the growth of root and shoot. Without water, the seed cannot start germination.

3. How do plants excrete?

Plants excrete by releasing excess water through stomata, shedding yellow leaves, resins, gums, and water droplets on leaf edges. These methods help remove waste substances from the plant body.

4. Describe one example of plant response to stimulus.

The touch-me-not plant closes its leaves when touched. Touch is the stimulus, and the folding of leaves is the plant’s response. This shows that plants can sense and react to changes around them.

5. Why is stagnant water harmful?

Stagnant water becomes a breeding place for mosquitoes. Mosquito larvae and pupae grow there and cause diseases like malaria and dengue. Therefore, stagnant water must be removed.

6. What is the importance of reproduction?

Reproduction ensures the continuity of life. If living beings do not reproduce, their species will end. It helps maintain the population of plants and animals.

7. Why do tadpoles live in water?

Tadpoles have gills and tails that help them swim. They breathe dissolved oxygen in water, so they cannot live on land until they grow legs and lungs.

8. Explain what germination means.

Germination is the process in which a seed starts growing into a seedling when it gets air, water, and suitable temperature. The seed coat breaks, roots emerge downward, and the shoot comes upward.

9. How are larva and pupa different?

Larva is active, swims freely, and feeds continuously. Pupa is inactive, does not feed, and is a stage where transformation into adult mosquito occurs.

10. What happens to a plant after it produces fruits?

After fruits form, the plant gradually stops growing and becomes dry. Finally, it dies even if water and sunlight are available.

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✨ 15 LONG QUESTIONS (70–100 words) WITH ANSWERS

1. Explain all characteristics of living beings in detail.

Living beings show several important life processes. They move, grow, and need food for energy. They breathe to get oxygen and remove waste through excretion. They respond to stimuli like touch, light, or sound. Living beings reproduce to increase their numbers. They also have a definite life cycle and die eventually. These characteristics together distinguish them from non-living things.

2. Describe seed germination with suitable conditions.

Seed germination begins when a seed absorbs water. Water softens the seed coat and activates the embryo inside. The seed also needs air for respiration and suitable temperature. Sunlight is not necessary for germination but is needed later for growth. After absorbing water, the root comes out first and grows downward. Then the shoot comes upward forming a seedling.

3. Explain movements in plants with examples.

Plants do not move from one place to another, but they show various kinds of movements. Flowers open and close depending on time of day. Sunflower turns toward sunlight. Insectivorous plants like Drosera close their sticky leaves when insects touch them. Touch-me-not plant folds its leaves when touched. Roots always grow downward while shoots grow upward.

4. Describe the life cycle of a frog.

A frog begins its life as a cluster of eggs called spawn. Eggs develop into embryos and then hatch into tadpoles. Tadpoles have tails and gills for breathing in water. As they grow, hind legs appear followed by front legs. This stage is called froglet. The tail becomes shorter and lungs develop. Finally, it becomes an adult frog able to live on land and water.

5. Describe the life cycle of a mosquito in detail.

The female mosquito lays eggs on stagnant water. These eggs hatch into larvae, which are worm-like and swim actively. Larvae grow and change into pupae which are comma-shaped. Pupae are inactive but breathe air. After some days, adult mosquitoes emerge. Adult mosquitoes fly away and the cycle continues. This life cycle includes four stages: egg, larva, pupa, adult.

6. Explain why frogs and mosquitoes undergo changes in their life cycles.

Frogs and mosquitoes undergo metamorphosis, which means they show major changes in body structure at different life stages. Tadpoles have gills and tails, while adult frogs have lungs and legs. Mosquitoes change from larva to pupa to adult. These changes help them adapt to their environment and survive better.

7. How do plants respond to sunlight and gravity?

Plants respond to sunlight by bending their shoots toward it. This is called phototropism. Roots respond to gravity and grow downward, which is called geotropism. Even if a seedling is placed upside down, the root bends downward and the shoot bends upward. These movements help the plant get sunlight and develop strong roots.

8. Explain why seeds do not germinate without air.

Seeds need oxygen for respiration to release energy. Without respiration, the embryo inside the seed cannot grow. If soil is fully waterlogged or seeds are kept in airtight places, oxygen cannot reach the seed and germination fails.

9. Explain the importance of removing stagnant water.

Stagnant water is a breeding ground for mosquitoes. Mosquito larvae and pupae grow in stagnant water and cause diseases like dengue, malaria, and chikungunya. Removing stagnant water breaks the mosquito life cycle and prevents diseases. Kerosene is also used to kill larvae by blocking air supply.

10. Describe the role of stomata in plants.

Stomata are tiny openings on the leaf surface. They help plants breathe by allowing oxygen to enter and carbon dioxide to exit. Stomata also control water loss through transpiration. They play an important role in photosynthesis and excretion.

11. Explain why reproduction is necessary.

Reproduction ensures that living beings continue to exist. Without reproduction, species will become extinct. It helps maintain population balance and allows transfer of characteristics from parents to offspring.

12. Explain with examples how plants respond to stimuli.

Plants respond to stimuli like touch, light, and gravity. Touch-me-not folds leaves when touched. Sunflowers turn toward sunlight. Roots grow downward due to gravity. Insectivorous plants trap insects when touched.

13. Explain why growth is a sign of life.

Growth means an increase in size, height, and body mass. Living beings grow from small to big. Plants grow from seeds to large trees. Humans grow from babies to adults. Non-living things do not grow on their own. Therefore growth indicates life.

14. Write a detailed note on excretion in living beings.

Excretion removes harmful waste from the body. Humans remove waste through urine, sweat, and breathing out carbon dioxide. Animals excrete through kidneys, lungs, and skin. Plants excrete by storing waste in fruits, gum, dropping leaves, and releasing water droplets. Without excretion, waste would accumulate and cause harm.

15. Explain how roots and shoots grow in different directions.

Roots grow downward due to gravity (positive geotropism). This helps the plant absorb water from soil and anchor itself. Shoots grow upward toward sunlight (positive phototropism) to make food. This directional growth helps plants survive and grow well.

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🔎 10 ASSERTION–REASON QUESTIONS (WITH ANSWERS)

1. Assertion: All living beings grow.

Reason: Growth is a permanent increase in size.
✔ Answer: A (Both assertion and reason are true, reason explains assertion)

2. Assertion: Plants do not move from place to place.

Reason: They are fixed in soil.
✔ Answer: A

3. Assertion: Seeds need water to germinate.

Reason: Water softens the seed coat.
✔ Answer: A

4. Assertion: Larvae of mosquitoes come to the water surface.

Reason: They need air for respiration.
✔ Answer: A

5. Assertion: Touch-me-not leaves fold on touching.

Reason: It is responding to a stimulus.
✔ Answer: A

6. Assertion: Plants are living beings.

Reason: They perform life processes like respiration and excretion.
✔ Answer: A

7. Assertion: A car moves on the road.

Reason: All moving things are living.
✔ Answer: D (Assertion is true, reason is false)

8. Assertion: Roots grow downward.

Reason: They grow towards sunlight.
✔ Answer: C (Assertion true, reason false)

9. Assertion: Mosquito population increases near stagnant water.

Reason: Stagnant water is required for egg laying.
✔ Answer: A

10. Assertion: Plants bend towards light.

Reason: Plants need sunlight to make food.
✔ Answer: A

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📚 5 CASE STUDIES WITH QUESTIONS & ANSWERS

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Case Study 1 – Seed Germination

A student planted four seeds in different pots.
Pot A: No water
Pot B: Excess water
Pot C: Moist soil, no sunlight
Pot D: Moist soil & sunlight

Questions

1. Which pot will show best germination?

2. Why will seeds in Pot A not germinate?

3. Why does excess water harm seeds?

Answers

1. Pot D

2. Lack of water prevents seed coat from softening.

3. Excess water removes air spaces in soil → no oxygen for respiration.

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Case Study 2 – Movement in Plants

A sunflower plant was kept in a room with sunlight coming from one window. After 3 days, the shoot bent toward the window.

Questions

1. What type of movement is this?

2. Why did the shoot bend?

3. Will the root also bend toward light?

Answers

1. Phototropism

2. Shoots grow toward sunlight.

3. No, roots grow away from light and towards gravity.

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Case Study 3 – Mosquito Control

A village had many dengue cases. Doctors found many open water containers near houses.

Questions

1. Why did mosquitoes breed there?

2. Which stage lives in water?

3. Name one method to stop breeding.

Answers

1. Stagnant water supports egg laying.

2. Larva and pupa.

3. Removing stagnant water or adding kerosene.

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Case Study 4 – Frog in Pond

During rainy season, students saw jelly-like masses floating on pond water.

Questions

1. What were those jelly masses?

2. What comes out of them?

3. Why do tadpoles live only in water?

Answers

1. Spawn (frog eggs)

2. Tadpoles

3. They have gills for breathing in water.

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Case Study 5 – Plant Life Cycle

A bean plant grew from a seed, produced flowers, fruits, and finally dried up.

Questions

1. What is this entire sequence called?

2. Why did the plant die even with water and sunlight?

3. What will happen to the seeds inside the fruit?

Answers

1. Life cycle of a plant

2. Life processes naturally stop with age.

3. They can grow into new plants.