Contents

Weeks Units Page No.

Unit 1 - The Human Circulatory System
 Function of the Heart
 Circulatory System
1&2 2-8
 The Circulatory System Questions
 Function of Blood
 Glossary
Unit-2 Keeping Healthy
 Healthy Diet
 Healthy and Sustainable Proteins
3  Legal and illegal drugs 9-16
 The Impact of Smoking and Alcohol
 Maintaining a Healthy lifestyle
 Diet and Exercises
Unit 3 - Why we group and classify living things
 Characteristics of Living Things
4  How and Why We Group Animals and Plants 10-23
 The 5Rs
 Say No to Plastics Poster (Exercise)

Unit 4 – Evolution and Inheritance

 How Living Things Have Changed Over Time
 Human Skulls: Using Evidence from the Past
5  Family Trees and Inheritance 24-31
 Inheritance Characteristics
 Animal and Plant Evolution: Evidence
 Glossary
Unit 5 - What is Light?
 Nature of Light
 Light Sources
 Light Travels in Straight Lines
6  Reflected Light 32-44
 How Shadows Form
 Shadow Shapes
 Using Light and Reflection
 Glossary/ Activity
Unit 6 - Climate Change and Sustainability
 Reducing Air Pollution
7  What Carbon Is 45-57
 Measuring Our Carbon Footprint
 The Sun, Wind, Water as an Energy Resource
 Glossary / Activity

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 Year 6 Science

Unit 1 - The Human Circulatory System

1. Function of the Heart

The heart is a muscular organ that pumps blood throughout the body. It has four chambers:
two atria and two ventricles. The right side of the heart pumps oxygen-poor blood into the lungs
for oxygenation, while the left side pumps oxygen-rich blood to the rest of the body. The heart
ensures continuous circulation, supplying oxygen and nutrients to tissues while removing waste
products like carbon dioxide.

Figure 1.1 Structure of Human Heart

The heart has three main functions:

 To pump blood throughout the body – The heart pumps blood to the lungs and to the rest of the
body. This blood delivers oxygen and nutrients to all cells and removes waste products.

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 To control the rhythm and speed of the heart rate – The heart rate is the number of times the
heart beats per minute. The heart rate is controlled by the nervous system and by hormones.

 To maintain blood pressure – Blood pressure is the force of blood against the walls of the
arteries. The heart helps to maintain blood pressure by pumping blood with enough force to
reach all parts of the body.

Label the parts of the heart system. Then use two different colors to show the difference.

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 2. Circulatory System

The circulatory system is an important part of our body. The word ‘circulatory’ means
something that is going round and round in a circle or loop. This is exactly what is happening
in our bodies all the time.

What Circulates and Why?

The simple answer is your blood circulates all around your body. Blood is doing an
important job - it is taking nutrients, hormones and oxygen all around the body to all the
places they need to go. The oxygen comes into your body when we breathe in, and it goes
into our lungs. Then, inside the lungs, this oxygen goes into our blood and starts its journey
around the body. You could think of the blood cells as a bit like delivery drivers that drop off
the oxygen to where it needs to be. Oxygen is dropped off all around the body to thinner
blood vessels, which transfer (move across) the oxygen to the cells in the body.

The Heart

The heart is at the heart of it all! Without the heart, no blood would get anywhere around
your body. The heart is basically a big pump that constantly pumps blood around the
circulatory system. This must happen all the time (even when you are asleep) to keep you
alive. There are two loops in the circulatory system; the first goes to and from the heart
visiting the lungs to collect oxygen and get rid of carbon dioxide. The other loop is much
larger and goes to and from the heart, but travels all around the body in between.

The Other Half of the System

We’ve talked about the blood in your system collecting oxygen, nutrients and hormones
and delivering them all around the body, but it also does another important job. It also takes
carbon dioxide from your body back to the lungs to be let out when you breathe out. If we
think of our red blood cell delivery drivers again, they also collect the waste and take it away
again. So, they are delivery drivers and waste disposers all in one!

Did You Know...?

• The average person’s heart will beat 2.5 billion times during a lifetime.

• Amazingly, it takes under 20 seconds for one red blood cell to go round the whole body.

• Red blood cells last about 4 months before your body makes new ones.

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Figure 1.2 The Circulatory System

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The Circulatory System Questions

1. What does ‘circulatory’ mean?

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2. What is circulated around the body with our blood? Circle one.
a. nutrients
b. oxygen
c. hormones
d. all of the above

3. In which organ does the oxygen go into the blood?

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4. Why are there two loops in the circulatory system? What does each one do?
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5. What waste product is removed through the lungs?
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6. How long does it take for one red blood cell to go round the body? Circle one.
a. 20 seconds
b. 20 minutes
c. 24 hours
d. 24 minutes
7. What are the blood cells compared to?
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8. Why is the heart so important? Use evidence from the text to explain fully.
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3. Function of Blood

Blood is a vital fluid that transports essential substances throughout the body. It consists of
red blood cells (which carry oxygen), white blood cells (which fight infections), platelets (which
help with clotting), and plasma (which carries nutrients, hormones, and waste products). Blood
plays a crucial role in maintaining homeostasis, regulating body temperature, and delivering S

Figure 1.3 Parts of Blood

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 4. Function of Blood Vessels

Blood vessels form a network that allows blood to circulate. There are three main types:

 Arteries: Carry oxygen-rich blood away from the heart to the body.

 Veins: Carry oxygen-poor blood back to the heart.

 Capillaries: Tiny vessels where the exchange of oxygen, nutrients, and waste occurs
between blood and tissues.

Figure 1.4 Types of Blood Vessels

Glossary

 Atria: Upper chambers of the heart that receive blood.

 Ventricles: Lower chambers of the heart that pump blood out.

 Plasma: The liquid part of blood carrying cells and nutrients.

 Arteries: Blood vessels that carry blood away from the heart.

 Veins: Blood vessels that carry blood to the heart.

 Capillaries: Small blood vessels where exchange of substances occur.

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 Unit-2 Keeping Healthy

1. Healthy Diet

A healthy diet consists of a balanced intake of essential nutrients, including

carbohydrates, proteins, fats, vitamins, and minerals. Consuming a variety of fruits, vegetables,
whole grains, and lean proteins supports overall health. Reducing processed foods, added
sugars, and excessive salt can help prevent obesity, diabetes, and heart disease. Hydration is also
crucial, and drinking enough water daily is essential for bodily functions.

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2. Healthy and Sustainable Proteins
Proteins are essential for muscle growth, tissue repair, and overall body function. Sustainable
protein sources include:
 Plant-based proteins: Beans, lentils, tofu, nuts, and quinoa.
 Lean animal proteins: Chicken, fish, and eggs.
 Alternative proteins: Lab-grown meat and insect-based proteins, which have a lower
environmental impact. Choosing sustainable proteins can reduce greenhouse gas
emissions and promote a healthier planet while maintaining proper nutrition.
A Balanced Diet Exercises

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3. Legal and Illegal Drugs

 Legal drugs: These include prescribed medications and over-the-counter drugs that help
manage health conditions when used correctly. However, misuse or overuse can lead to
dependency and health risks.

 Illegal drugs: Substances such as cocaine, heroin, and methamphetamine are harmful and
can lead to addiction, mental health issues, and severe bodily harm. Governments
regulate drug use to protect public health.

4. The Impact of Smoking and Alcohol

 Smoking: Tobacco contains nicotine, which is highly addictive. Smoking damages the
lungs, increases the risk of heart disease, and causes cancer. Secondhand smoke also
harms non-smokers.

 Alcohol: Excessive alcohol consumption affects the liver, brain, and heart. It can lead to
addiction, impaired judgment, and long-term health complications like liver disease and
high blood pressure. Avoiding smoking and limiting alcohol intake contribute to a
healthier lifestyle.

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5. Maintaining a Healthy Lifestyle

Living a healthy lifestyle involves:

 Regular exercise: Engaging in physical activity for at least 150 minutes per week
improves cardiovascular health and mental well-being.

 Adequate sleep: Getting 7-9 hours of sleep per night supports cognitive function and
immune health.

 Stress management: Practicing relaxation techniques such as meditation, deep breathing,

or engaging in hobbies helps reduce stress.

 Healthy social connections: Maintaining relationships and engaging in community

activities promote emotional well-being.

By following these practices, individuals can lead healthier, longer, and more fulfilling lives.

Now you have thought about ideas that may help you to get a good night’s sleep, make a
list of the top five things you think are important for everyone to do to get a good night’s
sleep. For example, not using devices for an hour before bedtime.

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2. --------------------------------------------------------------------------------------------------------------

3. --------------------------------------------------------------------------------------------------------------

4. --------------------------------------------------------------------------------------------------------------

5. --------------------------------------------------------------------------------------------------------------

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 Unit 3 - Why we group and classify living things

1. Characteristics of Living Things

All living things share seven essential characteristics, remembered by the acronym MRS GREN:

 Movement – They can move on their own (e.g., animals walk, plants grow toward light).

 Respiration – They use oxygen or other processes to release energy from food.

 Sensitivity – They respond to changes in their environment (e.g., plants bending toward
sunlight).

 Growth – They grow and develop over time.

 Reproduction – They produce offspring (babies, seeds, or spores).

 Excretion – They remove waste from their bodies.

 Nutrition – They take in food (plants make their own, animals eat other organisms).

Activity

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2. How and Why We Group Animals and Plants

Scientists group animals and plants based on similarities and differences. This is called
classification.

Grouping and classifying living things helps us:

 Understand how they are related.

 Make identifying new species easier.

 Study how they interact with their environment.

 Protect endangered species.

Animal Classification:

Animals are divided into vertebrates (with a backbone) and invertebrates (without a backbone).

 Vertebrates include:

o Mammals (e.g., humans, dogs) – warm-blooded, have fur, give birth to live
young.

o Birds (e.g., eagles, penguins) – have feathers, lay eggs, have beaks.

o Reptiles (e.g., snakes, lizards) – cold-blooded, have scales, lay eggs.

o Amphibians (e.g., frogs, salamanders) live in water and on land, have moist skin.

o Fish (e.g., sharks, goldfish) – live in water, have gills to breathe.

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 Invertebrates include:

o Insects (e.g., bees, ants) – six legs, exoskeleton.

o Arachnids (e.g., spiders, scorpions) – eight legs.

o Mollusks (e.g., snails, octopuses) – soft bodies, sometimes with shells.

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Plant Classification:
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Plants can be grouped as:

 Flowering plants (e.g., roses, apple trees) – reproduce with seeds inside flowers.

 Non-flowering plants (e.g., ferns, mosses) – reproduce with spores.

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3. The 5 Rs

The 5 Rs help us take care of the environment:

1. Refuse – Say no to things you don’t need (like plastic bags).

2. Reduce – Use less (like using less water and electricity).

3. Reuse – Find new ways to use things (like using a jam jar as a cup).

4. Recycle – Turn waste into new products (like making paper from old newspapers).

5. Rethink – think about what you are buying and if you really need it.

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 Unit 4 – Evolution and Inheritance

1. How Living Things Have Changed Over Time

 Species evolve through a process called natural selection.

 Over millions of years, animals and plants develop traits that help them survive.

 Example: Dinosaurs evolved into modern birds.

 Some species go extinct when they can't adapt to environmental changes, such as the
dodo.

 Changes in climate, natural disasters, and new predators or competitors can drive
evolution.

 Evolution happens slowly over thousands to millions of years.

2. Human Skulls: Using Evidence from the Past

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  Human skulls have changed in shape and size over time.

 Early human ancestors had smaller brains, larger jaws, and pronounced brow ridges.

 Modern humans have larger brains, smaller jaws, and a flatter face.

 Fossil skulls provide evidence of human evolution over thousands of years.

 Comparing human skulls with those of primates shows common ancestry with apes.

3. Family Trees and Inheritance

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  A family tree shows how traits are passed through generations.

 Scientists use family trees to track genetic traits in humans and animals.

 Example: Eye color, hair type, and blood type are inherited from parents.

 Dominant and recessive genes play a role in inherited characteristics.

 Some genetic traits can skip generations and reappear later.

4. Inherited Characteristics

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 Inherited traits come from parents and pass to offspring through DNA.

 DNA contains instructions for growth and development.

 Examples of inherited traits:

o Humans: Eye color, hair type, height, dimples, freckles.

o Animals: Fur color, beak shape, body size, webbed feet in ducks.

o Plants: Leaf shape, flower color, root type, fruit size.

 Some traits are influenced by the environment (e.g., tanned skin from the sun, muscle
growth from exercise).

 Certain diseases and conditions (e.g., color blindness) can be inherited genetically.

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5. Animal and Plant Evolution: Evidence

 Fossils show how animals and plants have changed over time.

 Comparing fossils of ancient and modern species shows gradual change.

 DNA studies help scientists understand relationships between species.

 Example: Whales evolved from land mammals that lived millions of years ago.

 Birds are closely related to dinosaurs, as shown by fossil evidence.

 Vestigial structures (body parts with no function) suggest evolution, like the human
tailbone or tiny leg bones in whales.

 Selective breeding in plants and animals (e.g., dog breeds, farm crops) shows how traits
can be changed over generations.

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Glossary

1. Evolution – The gradual change of species over time through natural selection.
2. Natural Selection – The process where organisms with traits that help them survive are
more likely to reproduce and pass on their traits.
3. Species – A group of living organisms that can breed and produce offspring.
4. Extinction – When a species completely dies out.
5. Fossil – The preserved remains or traces of ancient organisms.
6. Adaptation – A trait that helps an organism survive in its environment.
7. Ancestor – An early form of a species from which others evolved.
8. Inheritance – The process by which traits are passed from parents to offspring through
genes.
9. DNA (Deoxyribonucleic Acid) – The genetic material that carries instructions for growth
and development.
10. Genes – Units of DNA that determine traits, such as eye color or height.
11. Dominant Gene – A gene that is expressed even if only one copy is inherited.
12. Recessive Gene – A gene that is only expressed if two copies are inherited.
13. Family Tree (Pedigree) – A diagram that shows how traits are passed through
generations.
14. Selective Breeding – The process of breeding plants or animals to enhance specific traits.
15. Vestigial Structures – Body parts that have lost their original function over time (e.g.,
human tailbone).
16. Common Ancestry – The idea that different species share a distant relative in
evolutionary history.
17. Mutation – A change in DNA that can lead to new traits and affect evolution.
18. Variation – Differences in traits among individuals of a species.
19. Primate – A group of mammals that includes humans, apes, and monkeys.
20. Fossil Record – The collection of fossils that provides evidence of how species have
evolved over time.

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 Unit 5 - What is Light?

Nature of Light

Light is a type of energy that makes it possible for us to see the world around us.

We need light to see. Light comes from different sources called light sources; our main natural
light source is the sun. Other sources include fire, stars and man-made light sources such as
light-bulbs and torches.

Thanks to light, we see life in glorious color: our eyes see different wavelengths of light as
different colors.

Light appears to travel in straight lines, travelling from light sources until it hits the surface of
an object.

1. Light Sources

 Objects that produce their own light are called luminous objects (e.g., Sun, stars, light
bulbs, candles).

 Objects that do not produce light but can reflect it are called non-luminous objects (e.g.,
the Moon, mirrors, books).

 Two types of light sources:

o Natural sources (e.g., Sun, fireflies, bioluminescent organisms)

o Artificial sources (e.g., lamps, LEDs, torches)

 Types of objects based on light:

1. Transparent Objects – Allow most or all light to pass through.

Example: Glass, clear plastic, clean water.

2. Translucent Objects – Allow some light to pass through but scatter it, making objects
on the other side appear blurry.

Example: Frosted glass, thin fabric, wax paper.

3. Opaque Objects – Do not allow any light to pass through; they either absorb or reflect
all light.

Example: Wood, metal, bricks.

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Figure 5.1 Natural and Artificial Light

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Figure 5.2 Types of Objects by Light

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2. Light Travels in Straight Lines

 Light moves in straight paths called rays.

 This property is called rectilinear propagation of light.

 We can observe this with objects like laser pointers or a beam of sunlight through a
window.

3. Reflected Light

 Reflection occurs when light bounces off the surface.

 Smooth surfaces (like mirrors) create clear reflections.

 Rough surfaces scatter light, creating diffuse reflection (e.g., paper, walls).

 Laws of Reflection:

1. The angle of incidence = angle of reflection.

2. The incident ray, reflected ray, and normal lie on the same plane.

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4. How Shadows Form

 Shadows occur when an object blocks light because light travels in straight lines.

 The shape and size of the shadow depend on:

o The size of the object

o The position of the light source

o The distance between the object and the light source

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5. Shadow Shapes

 If the object is closer to the light source → larger shadow.

 If the object is farther from the light source → smaller shadow.

 The shape of the shadow matches the outline of the object but may appear distorted due
to the angle of light.

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6. Using Light and Reflection

 Mirrors are used in vehicles, periscopes, and telescopes to redirect light.

 Lenses (like those in glasses and cameras) focus or spread light.

 Fiber optics use internal reflection to transmit light signals in communication.

 Safety reflectors (on roads, bicycles) help make objects visible at night by reflecting
light.

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Glossary:

1. Reflection – The bouncing back of light from a surface.

2. Luminous Object – An object that produces its own light (e.g., the Sun).

3. Non-Luminous Object – An object that does not produce light but reflects it.

4. Shadow – A dark area created when an object blocks light.

5. Light Ray – A straight path along which light travels.

6. Opaque – A material that does not allow light to pass through (e.g., wood, metal).

7. Transparent – A material that allows most light to pass through (e.g., glass).

8. Translucent – A material that allows some light to pass but scatters it (e.g., frosted
glass).

9. Angle of Incidence – The angle between the incident ray and the normal line.

10. Angle of Reflection – The angle between the reflected ray and the normal line.

11. Refraction – The bending of light as it passes from one medium to another (e.g., air to
water).

12. Optic Nerve – The nerve that carries visual information from the eye to the brain.

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Activity for What is Light

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 Unit 6 - Climate Change and Sustainability

1. Reducing Air Pollution

 Air pollution is caused by harmful gases and particles in the air.

 Sources: Factories, cars, burning fossil fuels, wildfires.

 Effects: Health problems (asthma, lung disease), acid rain, climate change.

Figure 6.1 Sources of Air Pollution

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Figure 6.2 Sources, Pollution and Effects of Air Pollution

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 Ways to reduce air pollution:

o Using electric cars or public transport.

o Reducing the use of fossil fuels (coal, oil, gas).

o Planting trees to absorb carbon dioxide (CO₂).

o Recycling and using less plastic.

Figure 6.3 Ways to Reduce Air Pollution

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2. What Carbon Is

 Carbon is a natural element found in all living things.

 It is present in coal, oil, and natural gas, which we burn for energy.

 Carbon cycle:

o Plants absorb CO₂ from the air.

o Animals and humans release CO₂ when they breathe.

o Factories and vehicles add extra CO₂ to the atmosphere, causing global warming.

 Carbon Cycle is an important aspect of the survival of all life on earth. From an
environmental perspective, carbon provides insulation by trapping the sun’s heat. From a
biological perspective, carbon is the building block of life and forms stable bonds with
other elements necessary for life.

Figure 6.4 Carbon Cycle

3. Measuring Our Carbon Footprint

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 Carbon footprint: The amount of carbon dioxide (CO₂) we produce from daily
activities.

 Examples of high carbon footprint activities:

o Driving petrol cars.

o Using a lot of electricity.

o Eating food transported from far away.

Figure 6.5 Carbon Footprint

 Ways to reduce carbon footprint:

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 o Walking or cycling instead of driving.

o Using renewable energy (solar, wind, water).

o Eating locally grown food.

4. The Sun as an Energy Resource

 The Sun provides light and heat energy.

 Solar panels convert sunlight into electricity.

 Advantages:

o Renewable and free.

o No pollution.

 Disadvantages:

o Doesn’t work at night.

o Expensive to install.

Figure 6.6 Generating Solar Energy

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5. The Wind as an Energy Resource

 Wind turbines use wind to generate electricity.

 Advantages:

o Renewable and clean.

o No air pollution.

 Disadvantages:

o Needs strong wind to work.

o Can be noisy.

Figure 6.7 Generating Wind Energy

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6. Water as an Energy Resource

 Hydropower: Energy from moving water (dams, rivers, tides).

 Advantages:

o Renewable and reliable.

o No pollution.

 Disadvantages:

o Can harm fish and natural water flow.

o Expensive to build dams.

Figure 6.8 Generating Hydro Energy from Water

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Glossary:

1. Air Pollution – Harmful gases and particles in the air.

2. Carbon Dioxide (CO₂) – A gas produced when burning fossil fuels and breathing.

3. Carbon Footprint – The amount of CO₂ a person or activity produces.

4. Fossil Fuels – Natural fuels like coal, oil, and gas.

5. Solar Energy – Energy from the Sun.

6. Wind Energy – Electricity produced from wind using turbines.

7. Hydropower – Energy from moving water (dams, rivers).

8. Renewable Energy – Energy that comes from natural sources and won’t run out.

9. Sustainability – Using resources in a way that protects the environment for the future.

10. Greenhouse Effect – Trapping of heat in the atmosphere, leading to global warming.

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