Session 1: Introduction to Cells
Objective:
●​ To introduce the concept of cells as the building blocks of life.
●​ To understand how each cell has specific jobs and functions, and how cells
renew and replace themselves at different rates.
●​ To debunk the myth of the body completely replacing itself every 7 years,
showing the complexity of cell replacement.
Lesson Structure:
1. Starter (5 minutes)
●​ Prompt: "Who can tell me what makes up all living things? What do you think
living things are made of?"
●​ After hearing some answers, say:
○​ "Yes, that’s right! All living things are made of tiny parts, and these parts
are called cells. Today, we are going to learn about cells, the building
blocks of life!"
2. Brief Introduction to Cells (10 minutes) – Introduce the Concept
●​ Prompt: "How big do you think a cell is? Do you think we can see it with our
eyes?"
●​ Show a picture of a plant cell and an animal cell.
○​ Point to the picture: "This is a diagram of a plant cell and this is an
animal cell. They look similar, but there are also some differences we’ll talk
about later."
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○​ "Cells are so tiny that we can’t see them without a microscope, so we
need special tools to study them."
●​ Next, if you have a real microscope or a model, introduce it to the students.
○​ Prompt: "This is a microscope. Scientists use it to look at tiny things like
cells. What do you think we could see through this microscope?"
○​ Demonstrate how a microscope works (or show a video of cells under a
microscope if you don't have one).
○​ Prompt: "Cells are like the bricks of a building, but they’re much smaller.
All living things, whether they are plants, animals, or humans, are made
up of cells. Without cells, life wouldn’t be possible."
3. Discussion on Cell Replacement & The 7-Year
●​ Prompt: "We’ve heard that our bodies completely replace themselves every 7
years. Do you think that’s true? Let’s think about it together."
●​ Explain:
○​ "Well, some parts of our body do renew quickly. For example, skin cells
replace themselves every 28-30 days, so your skin gets a new layer
almost every month!"
○​ "But not all cells are replaced at the same speed. Some cells, like red
blood cells, live for about 4 months, while others, like certain brain cells,
can last a lifetime."
○​ "So, while many cells are always being replaced, not all of our body
completely changes every 7 years. It's more complicated than that."
●​ Prompt: "Why do you think it’s important for our cells to be constantly replaced?
What would happen if they didn’t replace themselves?"
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4. Cell Functions: A Tiny City Inside Your Body (10 minutes)
●​ Prompt: "Imagine each of your cells is like a tiny building in a city. What kinds of
things need to happen inside these buildings to keep the city running smoothly?
What jobs do the cells have to do every day?"
○​ Explain: "Cells have to provide energy, get rid of waste, communicate with
each other, and replace themselves when needed. Just like a busy city!"
●​ Prompt: "How do you think a cell gets its energy? And how does it get rid of
waste?"
○​ Use the analogy of a power plant for the mitochondria and waste disposal
for parts of the cell that manage waste.
○​ "Cells are like factories with their own power stations, waste disposal, and
even ‘communication systems’."
5. Worksheet Activity: Fill in the Blanks (10 minutes)​
Hand out a worksheet where students can fill in the answers based on what they’ve just
learned. They can write their responses in the blank spaces provided.
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Worksheet: Cells – Tiny Cities Inside Your Body
Part 1: Cell Functions
1.​ Cells need energy to work. Inside each cell, there are tiny powerhouses called
_____________. These parts give the cell energy, just like a power plant gives
energy to a city.
2.​ Cells also need to get rid of waste. Just like a city has rubbish collectors, cells
have parts that remove waste. These parts are called ____________ and
____________.
3.​ Cells talk to each other. This helps them work together in your body. They send
messages by using ____________.
Part 2: The 7-Year Myth
4.​ True or False: Our entire body completely replaces itself every 7 years.
○​ ______________ (Circle one: True / False)
5.​ Explain why the 7-year myth isn’t completely true. (Hint: Some cells, like brain
cells, can last a lifetime!)
○​
○​
6.​ How often are skin cells replaced?
○​
7.​ How long do red blood cells live?
○​
8.​ Some cells, like certain brain cells, last your whole life. Why do you think
some cells last longer than others?
○​
○​
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Part 3: Why Do Cells Need to Be Replaced?
9.​ Why is it important for your cells to be constantly replaced?
○​
○​
10.​Activity: Draw a picture of a cell as if it’s a building in a city. Label the parts of
the cell (like mitochondria, nucleus, etc.) and write what each part does.
●​ (Draw your cell in the space below)
6. Recap and Closing (5 minutes)
●​ Prompt: "So, what have we learned about cells today? Can anyone tell me one
thing that surprised them?"
●​ Review Key Points:
○​ Cells are like tiny cities with power stations, waste collectors, and
communication systems.
○​ Not all cells are replaced at the same speed—some renew quickly, while
others last much longer.
○​ The 7-year myth is a simplification; it’s not true for all cells in the body.
●​ Final Question: "How do you think knowing all of this about cells helps us
understand how our bodies work?"
Extension/Homework:
●​ Task: Research and find out how often different cells in the body are replaced.
For example, how long do muscle cells live? How about liver cells? Have them
add this information to their worksheet.
●​ Extension Activity: Choose one organ in the body (e.g., heart, liver, lungs) and
create a poster showing how the cells in that organ work together to keep the
body healthy.
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Worksheet: Cells – Tiny Cities Inside Your Body
Part 1: Cell Functions
1.​ Cells need energy to work. Inside each cell, there are tiny powerhouses called
_____________. These parts give the cell energy, just like a power plant gives
energy to a city.
○​ Answer: mitochondria
2.​ Cells also need to get rid of waste. Just like a city has rubbish collectors, cells
have parts that remove waste. These parts are called ____________ and
____________.
○​ Answer: lysosomes and vacuoles
3.​ Cells talk to each other. This helps them work together in your body. They send
messages by using ____________.
○​ Answer: signals (or chemical signals, messengers, electrical signals)
Part 2: The 7-Year Myth
4.​ True or False: Our entire body completely replaces itself every 7 years.
○​ Answer: False
5.​ Explain why the 7-year myth isn’t completely true. (Hint: Some cells, like
brain cells, can last a lifetime!)
○​ Answer: Not all cells in the body are replaced at the same rate. Some
cells, like skin and red blood cells, are replaced regularly, while other cells,
such as certain brain cells, last a lifetime. Some cells, like bone cells, take
about 10 years to fully renew.
6.​ How often are skin cells replaced?
○​ Answer: Every 28-30 days
7.​ How long do red blood cells live?
○​ Answer: Around 120 days
8.​ Some cells, like certain brain cells, last your whole life. Why do you think
some cells last longer than others?
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○​ Answer: Some cells, like brain cells, are specialized for specific jobs that
don’t require constant renewal, while other cells, like skin or blood cells,
are involved in processes that need frequent renewal (e.g., protecting from
damage, carrying oxygen).
Part 3: Why Do Cells Need to Be Replaced?
9.​ Why is it important for your cells to be constantly replaced?
○​ Answer: Replacing cells ensures that the body stays healthy and
functions properly. It helps replace damaged or old cells and keeps tissues
and organs working efficiently. For example, skin cells replace themselves
to protect us from germs, and red blood cells carry oxygen throughout our
bodies.
10.​Activity: Draw a picture of a cell as if it’s a building in a city. Label the parts of
the cell (like mitochondria, nucleus, etc.) and write what each part does.
●​ Answer: (This section will depend on the student’s drawings. A suggested list of
cell parts to label and explain can include:
○​ Nucleus: The ‘control centre’ of the cell, which sends instructions.
○​ Mitochondria: The ‘powerhouse’, which produces energy for the cell.
○​ Cell Membrane: The ‘outer wall’, which controls what enters and leaves
the cell.
○​ Cytoplasm: The ‘working space’ where other parts of the cell do their jobs.
○​ Lysosomes: The ‘clean-up crew’ that removes waste.
○​ Vacuoles: The ‘storage units’ for water and nutrients.)
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Session 2: Plant and Animal Cells
Objective:
●​ To compare and contrast the structures of plant and animal cells.
●​ To understand the unique features of plant cells, such as the cell wall and
chloroplasts.
●​ To observe how plant and animal cells have different functions, despite having
similar basic structures.
Lesson Structure:
1. Starter (5 minutes) – Recap from Last Lesson
●​ Prompt: "Can anyone remind me what we learned about cells last time? What
are some of the key things that cells need to do to keep us alive?"
●​ Quickly revisit the basic functions of cells (e.g., energy production, waste
removal, communication).
●​ Prompt: "Today, we're going to look more closely at two types of cells: plant cells
and animal cells. What do you think might be different between them?"
2. Introducing Plant vs. Animal Cells (10 minutes) – Discussion and Visuals
●​ Show a clear, labelled diagram of a plant cell and an animal cell.
○​ Prompt: "Take a look at these two cells. What do you notice about them?
Do they look the same or different? What are some parts they have in
common?"
●​ Explain:
○​ Both plant and animal cells have some basic parts, such as:
■​ Nucleus: The control centre of the cell.
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■​ Cell Membrane: The outer layer of the cell that controls what
enters and exits.
■​ Cytoplasm: The jelly-like substance that fills the cell and where
most chemical reactions happen.
○​ However, plant cells have some extra parts that animal cells don’t have:
■​ Cell Wall: A rigid outer layer that gives the plant cell its shape and
provides protection.
■​ Chloroplasts: These contain chlorophyll, which plants use for
photosynthesis (making food from sunlight).
■​ Large Vacuole: A large storage space for water and nutrients,
which helps maintain the shape of the plant cell.
●​ Prompt: "What do you think the extra parts in plant cells (like the cell wall and
chloroplasts) help the plant do that animal cells can’t? Why might animals not
need these extra parts?"
3. Group Activity: Comparing Plant and Animal Cells (10 minutes)
●​ Prompt: "Let's work together to compare the two cells. What would happen if a
plant didn't have a cell wall? Or if an animal cell had chloroplasts?"
●​ Break the students into small groups and give each group a set of materials to
work with:
○​ Diagrams of a plant and animal cell (printed).
○​ Markers or coloured pencils.
○​ Sticky notes for labelling parts.
●​ Task: Ask each group to identify and label the common parts of both cells, as
well as the unique parts found only in plant cells or only in animal cells.
●​ Extension: Challenge them to think of the role of the unique parts:
○​ Why does a plant need chloroplasts?
○​ Why do plants need a cell wall, and why don’t animals?
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Worksheet: Plant vs. Animal Cells
Part 1: Label the Cell Diagrams
Look at the diagrams of the plant and animal cells. Label each part of the cells. Here are
some parts to label:
●​ Nucleus
●​ Cytoplasm
●​ Cell Membrane
●​ Mitochondria
●​ Chloroplasts (in plant cells only)
●​ Cell Wall (in plant cells only)
●​ Vacuole
Part 2: Answer the Questions
1.​ What is the main difference between plant and animal cells?
○​
○​
2.​ What is the function of the chloroplast in plant cells?
○​
○​
3.​ Why do plant cells need a cell wall, but animal cells don’t?
○​
○​
4.​ What is the role of the vacuole in a plant cell?
○​
○​
5.​ True or False: Both plant and animal cells have a cell wall.
○​ _______________ (Circle one: True / False)
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6.​ Draw and Label: In the space below, draw your version of a plant cell and an
animal cell. Label the parts we discussed today.
○​ (Drawing space)
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Part 3: Compare the Cells
Write a paragraph comparing a plant cell and an animal cell. What are the differences in
the parts they have, and how do those differences help them do their jobs?
●​
●​
●​
●​
5. Recap and Closing (5 minutes)
●​ Prompt: "So, what did we learn today? How are plant cells and animal cells
different from each other, and what do these differences help them do?"
●​ Summary:
○​ Plant cells have unique parts like chloroplasts, a cell wall, and a large
vacuole, which help them make their own food, stay strong, and store
water.
○​ Animal cells have the basic cell structure but lack the extra parts because
animals don’t need to make their own food or have such rigid structures.
●​ Final Question: "Why do you think it’s important for plants to have chloroplasts?
Could animals survive if they had chloroplasts?"
○​ Let students share their thoughts, reinforcing the idea that plant cells are
designed for a different lifestyle (photosynthesis and growth), while animal
cells are more focused on movement, digestion, and response to the
environment.
●​ Optional: Write a short paragraph about how the structure of a cell is related to
its function. For example, how the shape of the cell allows it to do its job more
efficiently.
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Worksheet: Plant vs. Animal Cells
Part 1: Label the Cell Diagrams
Instructions: Look at the diagrams of the plant and animal cells. Label each part of the
cells. Here are some parts to label:
●​ Nucleus
●​ Cytoplasm
●​ Cell Membrane
●​ Mitochondria
●​ Chloroplasts (in plant cells only)
●​ Cell Wall (in plant cells only)
●​ Vacuole
Answer Key:
●​ Plant Cell:
○​ Nucleus: The control centre of the cell.
○​ Cytoplasm: The jelly-like substance where chemical reactions happen.
○​ Cell Membrane: The outer boundary that controls what enters and exits
the cell.
○​ Mitochondria: Powerhouses of the cell, providing energy.
○​ Chloroplasts: Found in plant cells, these are where photosynthesis
happens.
○​ Cell Wall: A rigid outer layer that gives the plant cell structure and
protection.
○​ Vacuole: A large storage space for water, nutrients, and waste.
●​ Animal Cell:
○​ Nucleus
○​ Cytoplasm
○​ Cell Membrane
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○​ Mitochondria
○​ Vacuole (smaller in animal cells than in plant cells)
Part 2: Answer the Questions
1.​ What is the main difference between plant and animal cells?
○​ Answer: The main difference is that plant cells have a cell wall,
chloroplasts, and a large vacuole, while animal cells do not have these
features.
2.​ What is the function of the chloroplast in plant cells?
○​ Answer: Chloroplasts allow plants to make their own food through
photosynthesis. They capture sunlight and use it to convert carbon dioxide
and water into glucose (sugar) and oxygen.
3.​ Why do plant cells need a cell wall, but animal cells don’t?
○​ Answer: The cell wall provides structural support and protection for the
plant. It helps the plant cell maintain its shape and prevents it from
bursting when it takes in water. Animal cells don’t need a cell wall because
they have a more flexible cell membrane, allowing them to move and
change shape.
4.​ What is the role of the vacuole in a plant cell?
○​ Answer: The vacuole stores water, nutrients, and waste. It helps maintain
the plant cell’s shape by keeping the cell turgid (full of water) and provides
a space for storage.
5.​ True or False: Both plant and animal cells have a cell wall.
○​ Answer: False​
(Only plant cells have a cell wall.)
6.​ Draw and Label: In the space below, draw your version of a plant cell and an
animal cell. Label the parts we discussed today.
○​ Answer: (This will depend on the student's drawings. A typical answer
would show the following labels:
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■​ For Plant Cell: Nucleus, Cytoplasm, Mitochondria, Cell Membrane,
Vacuole, Cell Wall, Chloroplasts.
■​ For Animal Cell: Nucleus, Cytoplasm, Mitochondria, Cell
Membrane, Vacuole (smaller).)
Part 3: Compare the Cells
Write a paragraph comparing a plant cell and an animal cell. What are the differences in
the parts they have, and how do those differences help them do their jobs?
Answer:​
Plant cells and animal cells are both similar in that they have basic parts like the
nucleus, cytoplasm, and mitochondria. However, plant cells have some extra structures
that animal cells do not have. For example, plant cells have a cell wall, which provides
strength and protection, and chloroplasts, which allow the plant to make its own food
through photosynthesis. Plant cells also have a large vacuole to store water and
maintain cell structure. In contrast, animal cells do not need a cell wall or chloroplasts
because animals obtain their food from outside sources, and their cells do not need the
extra rigidity of a cell wall. Instead, animal cells have a more flexible cell membrane and
often have smaller vacuoles. These differences help plant and animal cells carry out
their specific functions in the body.
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Session 4: Specialised Cells in the Human Body
Objective:
●​ To understand the concept of specialised cells and how their structure suits
their function.
●​ To learn about different types of specialised cells in humans, such as muscle
cells, nerve cells, and red blood cells.
●​ To understand how each cell is adapted to perform specific tasks in the body.
Lesson Structure:
1. Starter (5 minutes) –
●​ Prompt: "Can anyone think of different jobs that cells might have in the body?
What do you think makes a muscle cell different from a nerve cell or a blood
cell?"
●​ Activity: Write "muscle cell," "nerve cell," and "blood cell" on the board. Ask
students if they can guess what makes each cell type different.
●​ Prompt: "Today, we’ll learn how cells are specialised to do specific jobs."
2. Introduction to Specialised Cells (10 minutes) – Explanation and Discussion
●​ Prompt: "What do you think it means when we say a cell is specialised?"
○​ Explain: "When a cell is specialised, it means that its structure and
features are designed to do a very specific job in the body. The cell is
‘built’ in a way that helps it perform its job more efficiently."
○​ "For example, muscle cells are designed to contract and relax, nerve cells
are built to send messages, and red blood cells are built to carry oxygen."
●​ Discussion:
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○​ Muscle Cells: "Muscle cells are long and contain many mitochondria to
provide energy for movement. They work together to contract and help
your body move."
○​ Nerve Cells: "Nerve cells (neurons) are long and have long branches
called dendrites. These help them send electrical signals quickly to other
parts of the body."
○​ Red Blood Cells: "Red blood cells have a biconcave shape (like a
doughnut without a hole) that increases their surface area to carry oxygen
more efficiently. They also don’t have a nucleus, so there’s more space to
carry oxygen."
●​ Prompt: "Why do you think these cells are shaped the way they are? How does
their shape help them do their job?"
●​ Fat Cells (Adipocytes):
○​ Prompt: "Fat cells are very important for storing energy. Can anyone think
of why our bodies need fat?"
○​ Explain: Fat cells store energy as fat and help protect our organs. They
are designed to be large and can expand when we store extra energy.
Their structure is perfect for storing fat in the form of large vacuoles inside
the cell.
○​ Key Feature: Large vacuoles for fat storage.
●​ Epithelial Cells:
○​ Prompt: "Epithelial cells are found on surfaces and act like a protective
barrier. Can you think of where you might find them?"
○​ Explain: Epithelial cells line the surfaces of your body and organs, like
your skin, digestive tract, and lungs. They are tightly packed together to
form protective layers that help prevent infection and damage.
○​ Key Feature: Tightly packed together in layers, creating a protective
barrier.
●​ Stem Cells (Introduction):
○​ Prompt: "Stem cells are very special. They can change into any type of
cell in the body. Can you guess why stem cells are important?"
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○​ Explain: Stem cells are unique because they can turn into any type of cell
needed in the body. For example, they can become muscle cells, nerve
cells, or even red blood cells. They are found in early stages of
development and in some parts of the body throughout life, like bone
marrow.
○​ Key Feature: Stem cells are undifferentiated cells that can become any
type of cell in the body.
3. Group Activity: Investigating Different Specialised Cells (10 minutes)
●​ Prompt: "Let’s look more closely at these different types of specialised cells."
●​ Activity: In groups, give students printed images and descriptions of fat cells,
epithelial cells, and stem cells. Ask each group to:
○​ Identify the shape of the cell.
○​ Discuss the function of the cell.
○​ Explain the special features that help the cell do its job.
●​ Prompt: "How are fat cells different from red blood cells? Why are stem cells so
important for the body?"
4. Worksheet Activity: Specialised Cells (15 minutes)
●​ Hand out the expanded worksheet with new activities to help students
consolidate their understanding.
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Worksheet: Specialised Cells in the Human Body
Part 1: Matching Cells to Their Functions
Match the following types of cells with their correct function.
Muscle Cell
Nerve Cell
Stores fat to protect organs and provide energy.
Sends electrical signals to different parts of the
body.
Red Blood Cell
Fat Cell
Carries oxygen through the blood.
Lines surfaces like the skin and organs to protect
the body.
Epithelial Cell
Contracts to help move parts of the body.
Stem Cell
Can become any type of cell in the body and
helps with growth and repair.
Part 2: Fill in the Blanks
1.​ Fat cells store ___________ and help protect ___________ in the body.
2.​ Epithelial cells form a ___________ layer on the surface of your skin and
organs to protect them.
3.​ Stem cells are special because they can turn into any type of cell, such as a
muscle cell, nerve cell, or ___________ cell.
4.​ Muscle cells are long and have many ___________ to give them energy for
movement.
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Part 3: Compare Specialised Cells
Write a paragraph explaining how fat cells, epithelial cells, and stem cells are each
specialised for their particular jobs. Use specific examples of how their structure helps
them do their work.
Part 4: Drawing Activity
Draw and label the following cells:
●​ Fat Cell: Include the large vacuole for storing fat.
●​ Epithelial Cell: Show how these cells are packed together to form a protective
layer.
●​ Stem Cell: Draw a simple undifferentiated stem cell.
Extension:
●​ Task: Research bone cells or white blood cells and present how these cells
are specialised for their roles in the body.
●​ Optional Activity: Explore how stem cells are used in medical treatments (e.g.,
stem cell therapy for spinal cord injuries).
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Worksheet: Specialised Cells in the Human Body (With Answers)
Part 1: Matching Cells to Their Functions
1.​ Muscle Cell – e. Contracts to help move parts of the body.
2.​ Nerve Cell – b. Sends electrical signals to different parts of the body.
3.​ Red Blood Cell – c. Carries oxygen through the blood.
4.​ Fat Cell – a. Stores fat to protect organs and provide energy.
5.​ Epithelial Cell – d. Lines surfaces like the skin and organs to protect the
body.
6.​ Stem Cell – f. Can become any type of cell in the body and helps with
growth and repair.
Part 2: Fill in the Blanks
1.​ Fat cells store energy and help protect organs in the body.
2.​ Epithelial cells form a protective layer on the surface of your skin and organs to
protect them.
3.​ Stem cells are special because they can turn into any type of cell, such as a
muscle cell, nerve cell, or red blood cell.
4.​ Muscle cells are long and have many mitochondria to give them energy for
movement.
Part 3: Compare Specialised Cells
Answer Example:​
Fat cells, epithelial cells, and stem cells are all specialised for very specific jobs in the
body. Fat cells are large and store fat, which helps to protect organs and provide
energy. Epithelial cells are tightly packed together and form a protective layer that
shields the body from infection and damage. Stem cells are unique because they can
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change into any other type of cell in the body, making them important for growth and
repair. These cells’ special structures allow them to perform their functions effectively.
Part 4: Drawing Activity
Answer Example:
●​ Fat Cell: Draw a large cell with a big central vacuole storing fat.
●​ Epithelial Cell: Draw tightly packed cells in rows, forming a protective layer.
●​ Stem Cell: Draw a simple circle or oval cell, indicating that it can turn into
different types of cells (perhaps with arrows showing how it could change into a
muscle or nerve cell).
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