Transcript Nervous and Endocrine System

Nervous and
Endocrine System
Vocabulary
Gland – an organ that produces and
secretes (releases) hormones
 Hormone – a chemical created by the
body that regulates (control) specific
body functions
 Response – a reaction to a stimulus
 Stimulus – a change in the
environment that causes you to react
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Nervous System:
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Function: control and regulate all
Body
__________
activities
Respond (response) to a
Allows you to __________
__________(change
in the environment)
Stimulus
Stimulus: Smell of
Food
Response: Cat jump on
the stove
Stimulus: Hot stove
Response: Cat screams
and jumps off the
stove
Organs:
A. Brain
1. receives and ______________
messages
Interprets
2. Sends out ____________
messages
Response
3. Three areas
a) Cerebrum
Hemispheres
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i. Divided into two halves (______________)
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ii. Largest part of the brain
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iii. Controls ______________
muscles
Voluntary
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iv. Allows you to think, remember and speak
 b) Cerebellum
Movements
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i. Allows for smooth body _______________
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ii. Controls ____________
and posture
Balance
 c) Brain Stem
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i. Medulla Oblongata
Automatic
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ii. Controls _______________
processes
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ex. Breathing and heart rate
Organs:
Central Nervous System (CNS)
Peripheral Nervous
System – nerves from
the spinal cord
throughout the body
Organs:
B. Spinal Cord: sends messages between the
Brain
__________
and the body
C. Nerves
Carries
1. ____________
messages (nerve impulse)
Dendrite
2. Messages always travel from ___________
to
Axon Terminal
________________
3. Messages travel in the form of chemical and
Electrical
______________
signals
Synapse
4. _____________
is the space between two neurons
5. Messages travel across the synapse by
Neurotransmitter
_____________(chemicals released from the axon
terminal to trigger the nerve impulse on the next neuron)
Dendrite
Nucleus
Axon
Axon Terminal
Neurotransmitter
Dendrite
As the message travels through the neuron it’s an
electrical signal
As the message crosses the synapse (gap) it’s a
chemical signal
6. Three types of neurons:
A. Sensory neuron:
Receives
____________
(stimulus)
the message from
receptors
B. Interneuron: connects
sensory to motor neuron
C. Motor neuron: receives
message (response) and
tells effectors (muscles)
what to do
Neurons
Dendrites – receive the nerve impulse
 Nucleus – controls all activities of the cell
 Axon Terminals release neurotransmitters
into the synapse
 Nerve impulses travel from the dendrite
through the cell to the axon terminal (one
direction only)
 Nerve impulses travel through the cell as
electrical signals
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Endocrine System:
Function: control and regulate the body
Parts:
A. Glands: organs that
produces and secrete
Hormones
_____________
B. Hormones
Substances
1. _______________
produced that affects the
body
2. Transported by the
Circulatory
________________
system
3. Only affect their target
organ
Negative Feedback
Mechanism
1. Controls the levels of
hormones in your
blood
2. Production of one
hormone is controlled
by the amount of
another hormone in
the blood
3. Maintains
homoeostasis
Review – Simple Machines
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Simple Machines make work easier by reducing
the amount force needed or the distance that
the work is done for
Six Types:
Incline Plane ex. Ramp
Screw ex. Screw or jar lid
Wedge ex. Ax or knife
Pulley ex. Flagpole or clothesline the more
pulleys the less force you need
Wheel and Axle ex. Bicycle wheel
Lever ex. See saw or bat or wheel barrow
Review – Simple Machines
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Levers – three classes
FRE…123
F- Fulcrum (pivot point)
R- Resistance (object you want to move)
E- Effort (force you apply)
1st Class the fulcrum in the center ex. See saw
or crowbar
2nd class the resistance in the center ex. Wheel
barrow
3rd class the effort in the center ex. Shovel or
bat
Complex Machine is two or more simple
machines used together