Download Lesson 5 - The Nervous and Endocrine Systems - Hitchcock

Unit 1 Lesson 5 The Nervous and Endocrine Systems
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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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 spinalcord injuries are disorders of the nervous system.
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