7th Grade Health

What is the name of the control center for your body? What are some things that this center controls?

The nervous system7th Grade: Your body’s control center LEQ: How does the Nervous System communicate within your body and

protect you?

What does the nervous system control?

• The nervous system controls many things, almost everything in our bodies. Here is a list that probably could be much longer:

• Behavior • Cognition (the ability to reason and think) • Memory • Emotions • Metabolism • Homeostasis (keeping your body working properly) • Digestion • Respiration • Heart rate • Blood pressure • and much more...

CNS—The brain and spinal cord

Neurons

Did you know?

• Neurons are the oldest and longest cells in the body! You have many of the same neurons for your whole life. Although other cells die and are replaced, many neurons are never replaced when they die. In fact, you have fewer neurons when you are old compared to when you are young. The average adult has 85,000,000 ,000 neurons.

• Neurons can be quite large - in some neurons, such as corticospinal neurons (from motor cortex to spinal cord) or primary afferent neurons (neurons that extend from the skin into the spinal cord and up to the brain stem), can be several feet long!

The nervous system Summarization activity

• What are the two main sections of your Central Nervous System?

2 main parts of the nervous system

• Central Nervous System

• Peripheral Nervous System

THE NERVOUS SYSTEM

The nerves that connect the CNS to the rest of the body are called the Peripheral Nervous System.

The Somatic nervous system includes voluntary actions, these are actions that we control.

The Autonomic nervous system controls our life support systems that we don't consciously control, like breathing, digesting food, blood circulation, etc.

SIZE OF THE HUMAN BRAIN Human brain The average human brain weighs about 3 pounds.

At birth, the human brain weighs less than a pound (3/4 pounds). As a child grows, the number of cell remains relatively stable, but the cells grow in size and the number of connections increases. The human brain reaches its full size at about 6 years of age.

Learning Summarization activity

• What are the two main parts of the Peripheral Nervous System?

Peripheral Nervous System

• Somatic—Voluntary system—You choose

• Autonomic—Involuntary system—Your nervous system chooses for you.

Involuntary action is something you do without even thinking about it, for example breathing is a involuntary action. A voluntary action is something you purposefully do like throwing a ball, or jumping.It's easier to describe involuntary actions first. Basically, involuntary actions keep you alive and keep you safe. They are things which happen without you even thinking about them. These include behaviors like breathing, blinking, yawning, hiccoughs, and so on, or things like jerking your hand out of a fire, shivering when you're cold, or ducking when someone throws a ball at your face.

Voluntary actions are virtually everything else. Even walking is voluntary. You don't have to think about it when you do it, but it generally doesn't happen until you decide to do it.

Now, here's where the confusing part comes in. Many involuntary actions can become voluntary if you so choose. You can control your breathing or blinking, you can jerk your hand away, or you can duck. However, it's extremely difficult to shiver without being cold or to make yourself yawn or hiccough.

Similarly, you don't have to think about walking. That is, you don't have to think how to do it, but you're not doing it involuntarily. You're doing it subconsciously.

Peripheral Nervous System

• Think-Pair-Share

• What is the difference between the somatic and the autonomic systems? (page 298 text)

Speedy messenger service

• Did you know? There are nearly 45 miles of nerves that run through your body. They receive and send the messages that control all your body’s movements and processes. These messages travel as fast as 248 miles an hour.

COMPOSITION OF THE BRAIN  The brain consists of gray matter (40%) and white matter (60%) contained within the skull. Brain cells include neurons and glial cells.The brain has three main parts: the cerebrum, the cerebellum, and the brain stem (medulla). 

• NOURISHMENT OF THE BRAIN Although the brain is only 2% of the body's weight, it uses 20% of the oxygen supply and gets 20% of the blood flow. Blood vessels (arteries, capillaries, and veins) supply the brain with oxygen and nourishment, and take away wastes. If brain cells do not get oxygen for 3 to 5 minutes, they begin to die.

• Cerebrospinal fluid (CSF) surrounds the brain.

Dura Mater protects the brain

PROTECTION The cells of the nervous system are quite fragile and need extensive protection from being crushed, being infected by disease organisms, and other harm. The brain and spinal cord are covered by a tough, translucent membrane, called the dura mater. Cerebrospinal fluid (CSF) is a clear, watery liquid that surrounds the brain and spinal cord, and is also found throughout the ventricle (brain cavities and tunnels). CSF cushions the brain and spinal cord from jolts.

The cranium (the top of the skull) surrounds and protects the brain. The spinal cord is surrounded by vertebrae (hollow spinal bones). Also, some muscles serve to pad and support the spine.

More subtly, the blood-brain barrier protects the brain from chemical intrusion from the rest of the body. Blood flowing into the brain is filtered so that many harmful chemicals cannot enter the brain.

What is a concussion?

• Critical thinking (60 seconds with a partner)

1. Identify one symptom that you believe will be caused by a concussion.

2. List 2 things that you think could help someone recover from a concussion.

3. Name 3 long-term possible effects of a concussion.

Word Bank for Reading Assignment (pages 292-297)

Spinal cord neck Nerves (2) Spinal (3)

paralysis Nerve cells back accidents

Involuntary(2) pinched Neurons (2) protective

concussion somatic carelessness autonomic

central electrical Brain (3) two

injuries Nervous system Peripheral (2) Central

Voluntary (2) Peripheral

Taboo Game

brainconcussion Warrior Run

Middle School

Spinal cord Autonomic nervous system

Basketball

nerves electricity Heritage Days

Peripheral nervous system

pinched Wrestling

involuntary injuries Math class

accidents voluntary Ice Skating

paralysis protective Fishing

Parts of the brain• Cerebrum (Frontal lobe)—largest portion of brain. Controls the

senses, movement of muscles, thinking and speech• Cerebellum-- controls balance, posture, and coordination• Brain stem—controls vital body actions as heartbeat, breathing,

blood pressure and digestion• Meninges—membranes that cover the brain and the spinal cord• Occipital lobe—controls vision• Parietal lobe—ability to reason, process information, spatial

orientation, speech, visual perception• Temporal lobe--sensory input, auditory perception, language and

speech production, as well as memory association and formation.

Think-Pair-Share--Which part of your brain controls each action or thought?

• Hmm, looks like rain!• Ouch! The stove is hot!• It’s next to my ear.• I see a rainbow• I can walk and chew gum• I breathe and my heart beats.

Brain parts that control specific areas

• Hmm, looks like rain! Frontal lobe• Ouch! The Stove is hot! Parietal lobe• It’s next to my ear. Temporal lobe• I see a rainbow! Occipital lobe• I can walk and chew gum. Cerebellum• I breathe and my heart beats. Brainstem

Describe three involuntary and three involuntary actions. Identify the area(s) of the brain responsible.

Voluntary Involuntary

1.

2.

3.

4.

5.

Concussion

Concussion Quiz• 1. How many symptoms are needed to diagnose a concussion?• a) one b) two c) three• 2. Who is more susceptible to concussions, men or women?• 3. Does wearing a helmet prevent a concussion? YES or NO• 4. Have experts identified the part of the brain where a concussion occurs? YES

or NO• 5. True or False Genetics play a role in concussions.• 6. Who takes the longest to recover from a concussion?• a) child b) adolescent c) adult• 7. Can an X ray or Cat Scan diagnose a concussion? YES or NO• 8. Are concussions only caused by a direct impact to the head? YES or NO• 9. What is the only proven treatment for concussions?• 10. True or False You can only get a concussion through a sport or physical

activity. YES or NO

Pinched Nerve

Summarization activity

• What takes place in the nervous system when you catch a ball?

• Think-Pair-Share• Write out the steps and then discuss with your

partner.

Put these events in the correct order

• Arm and leg muscles move to catch the ball• Idea formed in the brain• Signal sent to muscles by the nerves• Eyes see the ball coming toward you• Signal sent to the brain by optic nerves

Catching a ball

• The muscular and nervous systems work together to catch a ball. The idea to catch the ball is formed in the brain when the eyes see the ball coming toward you. A signal is then sent to the brain by the optic nerves. Once the brain receives the signal, a new signal is sent to the muscles by the nerves, to the arm and the hand “telling” you to catch the ball.

Hunting Tree standhttps://www.youtube.com/watch?v=Bhg58pMNxLM

Tree stand accidents

Accidents and injuries

• Most spinal cord injuries result from accidents or carelessness. You can prevent them by acting safely and wearing protective gear when necessary.

Spinal cord injuriesCritical Thinking

• 30 seconds with a partner• Why do spinal cord injuries often result in

paralysis?

muscles parietal concussion memory system

Occipital doesnt functions cerebellum temporal

interpreted remember skull folded cortex

brain anything MRI brainstem

control frontal left

Brain Nerves memory occipital 3 pounds

muscles skull brainstem interpreted MRI

cerebrospinal fluid

temporal parietal remember functions

control Doesn’t bones frontal meninges

cerebellum anything left right cortex

millions system folded messages concussion

Socrative.com

• User name: __________________• Room name: _________________

Avoiding injury

• Think-pair-share• List 4 ways that you can avoid injury.(page 297 text) 1.2.3.4.

Caring for your body systems

• Rest• Exercise• Diet• StressTalk with a partner—Which of the areas listed above do you need to work on most? Write a sentence describing problems for each of three of the four above areas. Describe 3 specific actions you could take to improve your health.

Bill Nye video answers

1.Brain 2.System 3. remember4.Controls 5.Memory 6. functions7.Muscles 8.Folded 9. skull10.Interpreted 11.MRI 12. left13. Does not 14.Cortex 15. anything

Diseases and Disorders of the Nervous System

Disease or Disorder Description Treatment or Prevention

InfectionsPolio

Caused by a virus; can result in paralysis

Vaccination

Rabies Caused by a virus transmitted by bite of infected animal, can be fatal if untreated

Series of shots; avoid contact with strange animals

Meningitis Inflammation of membranes that cover brain and spinal column

Vaccine; antibiotics

Structural DisordersBrain tumor

Uncontrolled cell growth; may be cancerous

Surgery; additional treatment

Head injury Caused by a blow to the head; blood collects in damaged area and may cause pressure

Rest; surgery if necessary

Spinal cord injury Damage to the spinal cord Physical Therapy

Seizure DisorderEpilepsy

Brain disorder that causes uncontrollable muscle activity

Controlled by medication

Degenerative Diseases

Cerebral palsy Caused by damage or injury to the cerebrum; symptoms may vary

No cure; therapy can help victims live active lives.

Multiple sclerosis Caused by damage to protective outer coating of some nerves; symptoms may vary, but become progressively worse with time.

No cure; medication and therapy can help somewhat in the early stages