1. Unit 1 Lesson 5 The Nervous and Endocrine Systems
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2. Brainiac! What is the function of the nervous system?
Unit 1 Lesson 5 The Nervous and Endocrine Systems
Brainiac!
What is the function of the nervous system?
The nervous system is made up of the structures that control actions and reactions of the body in response to stimuli in the environment.
The nervous system has two parts: the central nervous system (CNS) and the peripheral nervous system (PNS).
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3. What is the function of the nervous system?
Unit 1 Lesson 5 The Nervous and Endocrine Systems
What is the function of the nervous system?
The CNS is made up of the brain and spinal cord.
The brain is the body’s central command organ.
The spinal cord allows the brain to communicate with the rest of the body.
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4. What is the function of the nervous system?
Unit 1 Lesson 5 The Nervous and Endocrine Systems
What is the function of the nervous system?
The PNS connects the CNS to the rest of the body.
Involuntary processes are those you have no control over, such as your heart beating.
Voluntary processes are actions your brain can control, such as moving an arm or a leg.
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5. What are the parts of the CNS?
Unit 1 Lesson 5 The Nervous and Endocrine Systems
What are the parts of the CNS?
The CNS is made up of the brain and the spinal cord.
The cerebrum is the largest part of the brain. It is where you think, solve problems, and store memories.
The cerebrum controls voluntary movements and processes information from your senses.
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6. What are the parts of the CNS?
Unit 1 Lesson 5 The Nervous and Endocrine Systems
What are the parts of the CNS?
The cerebellum processes information from your body, keeps track of body position, and coordinates movements.
The brain stem connects your brain to the spinal cord.
A part of the brain stem called the medulla controls involuntary processes in the body.
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7. What are the parts of the CNS?
Unit 1 Lesson 5 The Nervous and Endocrine Systems
What are the parts of the CNS?
Describe the part of the brain that made one activity that you did today possible.
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8. What are the parts of the CNS?
Unit 1 Lesson 5 The Nervous and Endocrine Systems
What are the parts of the CNS?
The spinal cord is a bundle of nerves protected by bones called vertebrae.
Nerves are a collection of nerve-cell extensions bundled together with blood vessels and connective tissue.
The spinal cord carries messages to and from the brain.
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9. You’ve Got Nerves! How do signals move through the nervous system?
Unit 1 Lesson 5 The Nervous and Endocrine Systems
You’ve Got Nerves!
How do signals move through the nervous system?
The nervous system translates environmental information into electrical signals.
A neuron is a special cell that moves messages in the form of fast-moving electrical energy.
These messages are called impulses.
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10. How do signals move through the nervous system?
Unit 1 Lesson 5 The Nervous and Endocrine Systems
How do signals move through the nervous system?
Signals move through the CNS and PNS with the help of glial cells that protect and support neurons.
Sensory neurons gather information from in and around your body and move it to the brain.
Motor neurons move impulses from the brain and spinal cord to other parts of the body.
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11. What are the parts of a neuron?
Unit 1 Lesson 5 The Nervous and Endocrine Systems
What are the parts of a neuron?
The cell body of a neuron has a nucleus and organelles.
A dendrite is a typically short, branched extension of the cell body.
The cell body gathers information from dendrites and creates an impulse.
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12. What are the parts of a neuron?
Unit 1 Lesson 5 The Nervous and Endocrine Systems
What are the parts of a neuron?
An axon is an extension of the neuron that carries impulses away from the cell body.
A neuron has only one axon.
At the end of the axon is the axon terminal that changes the electrical signal to a chemical signal, or neurotransmitter.
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13. What are the parts of a neuron?
Unit 1 Lesson 5 The Nervous and Endocrine Systems
What are the parts of a neuron?
How is a message transformed from an electrical message to a chemical message in a neuron?
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14. That Makes Sense! What are the main senses?
Unit 1 Lesson 5 The Nervous and Endocrine Systems
That Makes Sense!
What are the main senses?
The sensory organs sense the environment around you.
Sight allows you to see objects, motion, and light.
The front of the eye is protected by a membrane called the cornea.
Light passes through an opening called the pupil.
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15. What are the main senses?
Unit 1 Lesson 5 The Nervous and Endocrine Systems
What are the main senses?
Light-sensitive receptor cells, called rods and cones, in the retina change light into electrical impulses that are sent to the brain.
Impulses travel to your brain, creating an awareness of touch called a sensation.
The skin has different kinds of receptors that detect pressure, temperature, pain, and vibration.
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16. What are the main senses?
Unit 1 Lesson 5 The Nervous and Endocrine Systems
What are the main senses?
Hearing happens when sound-wave vibrations are turned into electrical impulses in the ear.
Sound is funneled through the outer ear, making the eardrum vibrate.
Tiny bones in the ear vibrate, causing the fluid in the cochlea to move in waves.
Hair cells in the fluid cause neurons to send electrical impulses to the brain via the auditory nerve.
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17. What are the main senses?
Unit 1 Lesson 5 The Nervous and Endocrine Systems
What are the main senses?
The tongue is covered with taste buds that contain taste cells. They respond to signals in dissolved molecules in food.
Olfactory cells react to chemicals in the air that dissolve in the lining of the nasel cavity, triggering signals.
The nose sends signals to the brain for processing taste and smell.
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18. Keep Your Cool! What is the function of the endocrine system?
Unit 1 Lesson 5 The Nervous and Endocrine Systems
Keep Your Cool!
What is the function of the endocrine system?
The endocrine system controls body functions and helps maintain homeostasis by using hormones.
A hormone is a chemical messenger made in one cell or tissue that causes a change in another cell or tissue elsewhere in the body.
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19. Unit 1 Lesson 5 The Nervous and Endocrine Systems
How do hormones work?
Hormones are produced by endocrine glands or tissues and travel through the bloodstream.
A gland is a group of cells that make special chemicals in your body.
Hormones only affect specific target cells that have a specific receptor to that hormone.
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20. What glands make up the endocrine system?
Unit 1 Lesson 5 The Nervous and Endocrine Systems
What glands make up the endocrine system?
The pituitary gland secretes hormones that control other glands.
The hypothalamus controls the release of hormones from the pituitary gland.
The pineal gland makes hormones that control sleep, aging, reproduction, and body temperature.
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21. What glands make up the endocrine system?
Unit 1 Lesson 5 The Nervous and Endocrine Systems
What glands make up the endocrine system?
The thyroid gland controls metabolism.
The parathyroid gland controls calcium in the blood.
Reproductive hormones control reproduction.
The pancreas regulates blood-sugar levels.
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22. Feedback How are hormone levels controlled?
Unit 1 Lesson 5 The Nervous and Endocrine Systems
Feedback
How are hormone levels controlled?
The endocrine system helps maintain homeostasis by increasing or decreasing hormone levels.
The endocrine system uses feedback to maintain homeostasis.
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23. How are hormone levels controlled?
Unit 1 Lesson 5 The Nervous and Endocrine Systems
How are hormone levels controlled?
A feedback mechanism is a cycle of events in which information from one step controls or affects a previous step.
In negative feedback, the effects of a hormone cause the release of that hormone to be turned down.
In positive feedback, the effects of a hormone stimulate the release of more of that hormone.
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24. Negative Feedback
BLOOD SUGAR LEVELS RISE AFTER EATING
DECREASED NORMAL BLOOD SUGAR LEVEL - PANCREAS TO STOP PRODUCING INSULIN
Hormone levels are kept from rising to high. System turns itself off or inhibits more production
HIGH BLOOD SUGAR LEVELS CAUSE PANCREAS TO RELEASE INSULIN
INSULIN DECREASES BLOOD SUGAR LEVELS

25. POSITIVE FEEDBACK In positive feedback hormone levels continue to rise
BLOOD VESSEL IS DAMAGED & PLATELETS CLING TO SITE
PLATELETS RELEASE CHEMICALS ATTRACTING OTHER PLATLETS
PLATELETS PILE UP ATTRACTING OTHER PLATELETS UNTIL CLOT FORMS

26. What are disorders of the endocrine and nervous systems?
Unit 1 Lesson 5 The Nervous and Endocrine Systems
What are disorders of the endocrine and nervous systems?
Hormone imbalances can happen when the endocrine system makes too much or too little of a hormone.
Type 1 diabetes is caused by a hormone imbalance.
Parkinson’s disease, multiple sclerosis, and spinal-cord injuries are disorders of the nervous system.
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