Unit 8 Lesson 1 What Are Organs and Body
Systems?
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Unit 8 Lesson 1 What Are Organs and Body Systems?
Florida Benchmarks
• SC.5.L.14.1 Identify the organs in the human
body and describe their functions, including the
skin, brain, heart, lungs, stomach, liver,
intestines, pancreas, muscles and skeleton,
reproductive organs, kidneys, bladder, and
sensory organs.
• SC.5.L.14.2 Compare and contrast the function of
organs and other physical structures of plants and
animals, including humans, for example: some
animals have skeletons for support—some with
internal skeletons, others with exoskeletons—
while some plants have stems for support.
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Unit 8 Lesson 1 What Are Organs and Body Systems?
Building a Body
• An organism is a living thing.
• An organism is made of parts that work together
to meet its needs.
• An organ is a body part that is made up of
smaller parts that work together to do a certain
job.
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Unit 8 Lesson 1 What Are Organs and Body Systems?
Building a Body
• An organ system is a group of organs that work
together to do one type of job.
• Animals and plants are organisms. Both have
organs that work to help them live.
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Unit 8 Lesson 1 What Are Organs and Body Systems?
Building a Body
• Eyes are organs that help you see.
• Bones are organs. Bones support your body.
• Muscles are organs that help you move.
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Unit 8 Lesson 1 What Are Organs and Body Systems?
Building a Body
• The skin is the largest organ in your body.
• Skin protects your body from germs and keeps
your body from drying out.
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Unit 8 Lesson 1 What Are Organs and Body Systems?
The Information Highway
• Sensing your surroundings and communicating
information are the jobs of your nervous system.
• Nerves are made up of long chains of nerve cells.
• Different nerves send and receive information.
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Unit 8 Lesson 1 What Are Organs and Body Systems?
The Information Highway
• Nerves carry information to and from the brain,
which organizes and processes information.
• The spinal cord is the main pathway for
information traveling to and from the brain.
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Unit 8 Lesson 1 What Are Organs and Body Systems?
The Information Highway
• Identify the brain, spinal cord, and nerves in the
image below.
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Unit 8 Lesson 1 What Are Organs and Body Systems?
Sensing Surroundings
• Senses are your body’s way of gathering
information about the world around you.
• Senses include sight, hearing, smell, touch, and
taste.
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Unit 8 Lesson 1 What Are Organs and Body Systems?
Sight
• Eye color is from a muscle called the iris.
• Light enters the pupil and passes through a lens.
• The retina at the back of the eye contains nerve
cells that detect light.
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Unit 8 Lesson 1 What Are Organs and Body Systems?
Hearing
• The outer ear funnels information into the middle
ear.
• Sound vibrations are passed to tiny bones called
the hammer, anvil, and stirrup.
• These bones pass vibrations to a fluid-filled
structure in the inner ear called the cochlea.
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Unit 8 Lesson 1 What Are Organs and Body Systems?
Hearing
• From the cochlea, tiny hairs transfer the vibrations
to nerve cells.
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Unit 8 Lesson 1 What Are Organs and Body Systems?
Smell
• Inside the nose, tiny structures sense chemicals in
the air.
• These structures are attached to nerve cells in the
olfactory bulb that send messages to the brain.
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Unit 8 Lesson 1 What Are Organs and Body Systems?
Taste
• Taste buds on your tongue sense chemicals.
• Taste buds are attached to nerves that send
messages to the brain about the chemicals they
sense.
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Unit 8 Lesson 1 What Are Organs and Body Systems?
Sensory Overload
• Different animals use senses differently. Bats and
dolphins “see” by the echo of sounds in their ears.
• Moths have antennae on their head that can
detect chemicals in the air.
• The Venus flytrap has sensitive leaves with hairs
that can detect touch.
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Unit 8 Lesson 1 What Are Organs and Body Systems?
The Skin You’re In
• The organ covering your body is a protective layer
called skin.
• Skin, fingernails, toenails, and hair are part of the
integumentary system.
• The integumentary system protects the inside of
the body.
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Unit 8 Lesson 1 What Are Organs and Body Systems?
The Skin You’re In
• Skin keeps germs out of the body.
• Skin helps keep in water.
• Sweat on the skin cools the body.
• Hair protects your skin.
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Unit 8 Lesson 1 What Are Organs and Body Systems?
The Skin You’re In
• The epidermis is your outer layer of skin.
• The dermis is the inner layer of skin. It contains
hair follicles, sweat glands, blood vessels, and
nerve cells.
• Nerve endings are special structures that sense
things around you.
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Unit 8 Lesson 1 What Are Organs and Body Systems?
The Skin You’re In
• Identify the epidermis, dermis, hair follicles, and
nerve endings in the image below.
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Unit 8 Lesson 1 What Are Organs and Body Systems?
Plant and Animal Coverings
• Different animals are covered by different skin
coverings for protection.
• Fur, feathers, scales, and shells are examples of
animal coverings.
• Plants are covered by bark, sharp spines, or waxy
coatings to protect them.
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