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Pre-K through Grade 2
Grade 3 through Grade 6
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Grade Levels Grades 3 through
5
Estimated Teaching Time 25
minutes
Interdisciplinary Connections
- Observing a demonstration (Science)
Objectives
Students will learn what skin looks like and understand its purpose.
What Students Do
Students will use food items to visualize the skin’s structure
and to see how it acts as a protector.
Materials Required
- Banana
- Three slices of bologna
- Six to eight slices of pimento loaf
- Six to eight slices of salami
- Cross-section illustration of the skin (blackline
master 2.1 PDF)
- Crayons
Advanced Preparation
Peel a banana skin and let it dry for three or four days.
Suggested Sequence
- Brainstorm with students how our skin can protect and help us.
- Ask students why they think a banana has a skin (the banana
peel).
- Peel the banana to demonstrate that the skin protects the inside
of the banana. Explain to students that the peel protects the
banana the way our skin protects our bodies. Ask students to hypothesize
what will happen to the banana peel after a few days. Show them
the dried banana peel.
- Stack the bologna slices on top of the pimento loaf slices.
Then, stack both on top of the salami. Trim them into squares.
Explain that this is similar to what a cross-section of their
skin would look like. Tell students that the thick bottom layer
of their skin (the subcutaneous layer) is fatty, like the salami.
It helps to warm and cool the body, protects it from shock, and
passes nutrients to the top layer of skin. The middle layer (the
dermis) has sebaceous glands which produce oil that lubricates
our skin so it doesn’t dry out like the banana peel.
- As you remove one slice of bologna (which represents the epidermis),
explain that we have many layers of skin. For example, when you
get sunburned and your skin peels, only the top layer of skin
comes off leaving the living layer beneath it exposed.
- Pass out copies of the cross-section illustration and ask students
to identify which parts of the skin are represented by the bologna
[epidermis], the pimento loaf [dermis] and the
salami [subcutaneous layer]. Ask them to color in the
layers.
Check for Understanding Ask the
following questions:
- How is our skin similar to a banana peel?
- Why did we use fatty salami for our demonstration?
- How does the fatty bottom layer help our bodies?
- Why did we choose pimento loaf for the dermis? What do the
pieces of peppers and olives represent? [Nerves, blood vessels,
sebaceous glands, sweat glands and hair follicles.] How does
the dermis help us?
Extensions
Experiment with other fruits containing a skin, or outer layer,
by peeling the fruit and putting the skin aside. Which fruit dries
out or withers the quickest? What does that tell you about the fruit?
Words to Share
- Blood vessel
- Cross-section
- Dermis
- Epidermis
- Hair follicle
- Nerve
- Nutrients
- Sebaceous gland
- Subcutaneous layer
- Sweat gland
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