4.1 Lesson 3: Nervous System

is made up of the structures that
control actions and reactions of
the body in response to stimuli in

the environment

word stimuli

mean?

Give some
examples.

Open Ended

What does the word Stimuli mean?

The nervous system is like the body's
communication network. It's made up of the
brain, spinal cord, and nerves. Its main
function is to send messages between the
brain and the rest of the body. These
messages, called nerve impulses, help us do
everything from moving our muscles to
sensing the world around us.

The 2 parts of the Nervous System

Central Nervous

System

Peripheral Nervous

System

“Outside”
organs are
the nerves

“Main” organs
are the brain
and the spinal

cord

The nervous system processes information

from our senses by detecting stimuli,

transmitting signals to the brain, processing the

information, and generating appropriate

responses. This process allows us to interact

with the world around us and respond to

changes in our environment.

The brain is ALWAYS processing information

Sensory neurons gather information from in
and around your body and move it to the
brain.

The nervous system translates information
intoelectrical signals.

●

Electrical signals are calledimpulses.

Brain: Think of the brain as the boss of the nervous system. It's like

a supercomputer that controls everything we do. Here's what it
does:
●

Cerebrum: This is the thinking part of the brain. It helps us learn,
remember things, and make decisions.

●

Cerebellum: Imagine it as the balance and coordination center.
It helps us walk, run, and do other movements smoothly.

●

Brainstem: This is like the body's autopilot. It controls things we
don't have to think about, like breathing and heart rate.

Spinal Cord: Picture it as a superhighway that connects
the brain to the rest of the body. It's like a long, thin tube
running down our backs. Here's what it does:

● Gray Matter: This is where the nerve cell bodies live. It

helps process information and send signals.

● White Matter: Think of it as the cables carrying

messages. It helps signals travel up and down the spinal
cord quickly.

The brain processes information by receiving
messages from our senses, sending signals to different
parts of the brain to analyze the information, making
decisions based on what it knows, and then sending
commands to the body to respond accordingly. It's like
the control center of our body, helping us understand
the world around us and decide how to act.

The nervous system contributes to
homeostasis by detecting changes in the
body, sending signals to the brain, which
then responds by sending commands to the
body to maintain balance. This helps ensure
that the body's internal environment stays
stable and healthy.

In summary, the central nervous system
includes the brain and spinal cord. The
brain helps us think, remember, and
move, while the spinal cord acts as a
communication pathway between the
brain and the rest of the body.

​Time to Climb Checkpoint 1

Multiple Choice

What is the main function of the Nervous system?

• Controls movement of muscles

• Regulates body temperature

• Processes information and sends messages throughout the body

• Helps digest food

Multiple Choice

The two main parts of the Nervous System are:

• Brain and Spinal Cord

• Brain and Heart

• Heart and Lungs

• Lungs and Stomach

Multiple Choice

How does the nervous system process information from your senses?

• By sending messages only to the muscles

• By ignoring information from the senses

• By sending signals to the brain and interpreting them

• By storing the information in the muscles

Multiple Choice

Identify the parts of the Central Nervous System.

• The brain and the spinal cord.

• The heart and the lungs.

• The liver and the stomach.

• The kidneys and the bladder.

Multiple Choice

How does the brain process information?

• By sending signals to the muscles

• By comparing new information with what it already knows and making decisions

• By storing information in the stomach

• By releasing hormones

Multiple Choice

How does the nervous system contribute to homeostasis throughout the body?

• By controlling movement of muscles

• By regulating body temperature

• By digesting food

• By helping with breathing

Multiple Choice

Which part of the nervous system helps maintain balance and coordination?

• Brainstem

• Cerebrum

• Cerebellum

• Spinal Cord

Multiple Choice

Which part of the nervous system is the thinking part of the brain?

• Brainstem

• Cerebrum

• Cerebellum

• Spinal Cord

Brain:
● Controls everything you do and feel.
● Helps you think, learn, remember, and feel emotions.
● Made up of different parts:

● Cerebrum: Thinks and decides things.
● Cerebellum: Helps you balance and move

smoothly.

● Brainstem: Keeps your body working, like breathing

and heart rate.

Spinal Cord:

● It's like a superhighway that connects your

brain to the rest of your body.

● Runs down your back inside your spine.
● Helps send messages between your brain and

body parts, like moving muscles and feeling
sensations.

Autonomic Nervous System:

● Works automatically without you having to think

about it.

● Controls things like your heartbeat, breathing,

digestion, and sweating.

● Keeps your body running smoothly and helps you

respond to stress or danger without you having to
do anything.

Somatic Nervous System:

● Helps you move your muscles voluntarily, like

when you walk, run, or jump.

● Receives signals from your brain that tell your

muscles what to do.

● Controls your senses, allowing you to feel

things like touch, pain, heat, and cold.

Central Nervous System (CNS):

● It's like the boss of your body's nervous

system.

● Includes your brain and spinal cord.
● Controls everything you do and feel, like

thinking, moving, and feeling emotions.

Peripheral Nervous System (PNS):

● It's like the messenger system of your body's

nervous system.

● Includes all the nerves outside of your brain and

spinal cord.

● Helps your brain communicate with the rest of your

body, sending messages to your muscles, organs,
and senses.

​Time to Climb Checkpoint 2

Multiple Choice

Which part of the nervous system processes information that comes from the senses and sends signals to the body for responses?

• Brain

• Spinal Cord

• Somatic

• Automatic

Multiple Choice

What is the primary function of the spinal cord?

• Sending signals to and from the brain

• Processing thoughts and emotions

• Controlling voluntary actions

• Sending signals to the skeletal muscles

Multiple Choice

Which part of the nervous system controls voluntary actions like moving your arm?

• Brain

• Spinal Cord

• Somatic

• Automatic

Multiple Choice

Which part of the nervous system is responsible for involuntary responses like heart beating and digestion?

• Brain

• Spinal Cord

• Somatic

• Automatic

Multiple Choice

What is the main function of the central nervous system?

• Controlling voluntary movements

• Regulating heart rate

• Processing information and sending signals to and from the body

• Sending signals to the skeletal muscles

Multiple Choice

Where does most of the processing of information happen within the nervous system?

• Spinal Cord

• Peripheral Nervous System

• Brain

• Somatic

Multiple Choice

Which part of the nervous system consists of the nerves throughout the body?

• Brain

• Spinal Cord

• Central Nervous System

• Peripheral Nervous System

Multiple Choice

What is the role of the peripheral nervous system?

• Processing thoughts and emotions

• Controlling voluntary actions

• Sending signals to and from the body to the central nervous system

• Sending signals to the skeletal muscles

Open Ended

Exit Ticket: Complete a 3-2-1 Summary of the Nervous System

• Three things you have learned

• Two things you found interesting

• One question you still have