Download packet - mybiologyclass

Name: ___________________________________ Date: ____________ Class: ______
Page 1/9
UNIT PACKET FOR The Nervous System
kMA Frameworks:
MA LS 4.4 Explain how the nervous system (brain, spinal cord, sensory neurons, motor neurons) mediates communication between different parts of the body and the body’s interactions with the environment. Identify the basic unit of the
nervous system, the neuron, and explain generally how it works.
MA LS 4.7 Recognize that communication between cells is required for coordination of body functions. The nerves communicate with electrochemical signals, hormones circulate through the blood, and some cells produce signals to
communicate only with nearby cells.
MA LS 4.8 Recognize that the body’s systems interact to maintain homeostasis. Describe the basic function of a physiological feedback loop.
28.1 – The nervous system links sensation to response
28.2 – Neurons conduct nerve impulses
28.3 – The PNS carries information to and from the CNS
28.4 – The CNS integrates nervous information
28.5 – Sensory receptors link the environment to the nervous system
OBJECTIVES:
Put on your review sheet:
1. Differentiate between sensory neurons, interneurons, and motor neurons.
2. Differentiate between the central nervous system and the peripheral nervous system
3. Differentiate between the autonomic and somatic nervous systems
4. Identify and give the functions of the three main regions of the brain (Cerebrum, Cerebellum, Brainstem)
5. Describe the functions of the right and left hemispheres of the cerebrum.
6. Identify the function of the hypothalamus
7. Define homeostasis
Be able to do by practicing:
8. Match each of the key terms to its correct definition
9. Given a picture of a neuron, diagram the path of a nerve impulse
10. Label the main parts of the brain on a diagram
11. Label the parts of a neuron on a diagram
12. Solve a problem similar to the activity we did in “the brain and its functions.” Given parts of the brain and the areas of the body they govern,
tell what might happen to the body if certain parts of the brain were damaged. (You will be given all of the information, you will just have to
know how to use it)
KEY TERMS:
28.1 – The nervous system links sensation to response
Central Nervous System (CNS): the body’s primary information processing system; includes the brain and spinal cord
Interneurons: nerve cell located entirely in the central nervous system that integrates sensory information and sends motor commands
Motor Neuron: nerve cell that carries signals from the central nervous system to muscle or gland cells.
Neuron: nerve cell; basic unit of nervous tissue
Peripheral Nervous System (PNS): network of nerves carrying signals into and out of the CNS.
Reflex: rapid, automatic response to a stimulus
Response: reaction to an event
Reflex Arc: The nervous system pathway that regulates a reflex
Sensory Neuron: nerve cell that carries information from the environment to the CNS
Stimulus: environmental change that triggers a reaction
28.2: Neurons conduct nerve impulses
Axon: neuron fiber that carries electric impulses away from the cell body and toward other cells
Dendrites: neuron fiver that receives signals and carries them toward the cell body
Myelin sheath: thick coat of material that surrounds and insulates the axon of some neurons
Node: the spaces on an axon between the myelin
Neurotransmitter: chemical that carries information from one neuron to another or to another cell
Synapse: where two neurons meet and electrical or chemical signals are relayed between the two
28.3:The PNS carries information to and from the CNS
Autonomic Nervous System: carries signals to internal organs
Somatic Nervous System: carries signals from the CNS to skeletal muscles
28.4:The CNS integrates nervous information
Brainstem (medulla): lower section of the brain that filters information going to and from the brain
Cerebellum: part of the brain located below the cerebrum and above the spinal cord; planning center that coordinates body movement.
Cerebrum: largest and most complex part of the brain, made up of the left and right hemispheres
Homeostasis: internal stability
Hypothalamus: portion of the brain that maintains homeostasis of the body
Name: ___________________________________ Date: ____________ Class: ______
Page 2/9
Name: ___________________________________ Date: ____________ Class: ______
Page 3/9
Label the following on
the Neuron below:
Nucleus, Dendrites,
Axon, Myelin sheath,
Axon terminals, end
brush
Color code the following parts in the Neuron and mark the color
you used in the box:
 Nucleus
 Dendrites
 Axon
 Myelin sheath
 Axon terminals (endings)
 End brush
 Cell Body
Name: ___________________________________ Date: ____________ Class: ______
Page 4/9
NOTES: 28.1 – The nervous system links sensation to response
Structure and Functions of the Nervous System
 Basic unit: Neuron (nerve cell)
 Parts of the nervous system:
o CNS: Central Nervous System
 Made of brain and spinal cord
o PNS: Peripheral Nervous System
 Made of all nerves outside of the CNS.
Flow of Information in the Nervous System
 Sensory Input: the PNS receives information about environmental change (stimulus), then sensory neurons
carry the information from the PNS to CNS.
 Integration: the CNS interprets the information sent from the PNS
o Involves neurons located entirely within the CNS, called interneurons.
 Motor Output: the CNS orders a response
o Neurons that carry such signals away from the CNS are called motor neurons.
Reflexes
 A reflex is an automatic response
 The nervous system pathway that regulates a reflex is called a reflex arc.
 Example: During a physical, your doctor has probably performed a test by striking your knee with a rubber
hammer. Without thinking about it, your lower leg quickly jerks forward – a reflex.
Example of A Reflex Arc
Name: ___________________________________ Date: ____________ Class: ______
Page 5/9
NOTES: 28.2 - Neurons conduct nerve impulses
Neurons
• Neurons are the specialized cells that transmit information around the body.
• They are the basic unit of the nervous system
Structure of a Neuron
• Dendrites: receive signals and carry them toward the neuron’s cell body
• Axon: a fiber that carries electrical impulses away from the cell body and toward other cells
• Axon terminals: play a role in transmitting information to other cells
• Myelin sheath: insulates the axon, allows signal to travel down the axon faster.
Types of Neurons
• Sensory Neurons: bring impulses toward spinal cord and brain
• Interneurons: interpret information sent to brain and spinal cord
• Motor Neurons: bring impulses away from brain and spinal cord
Synapse
• Synapse: space separating the axon of one neuron from the dendrite of another
• At end of axon there are vesicles filled with a chemical called a neurotransmitter. This is the chemical that
neurons use to communicate with each other.
Conduction of Impulse
• When there is a stimulus, the impulse moves from the dendrites to the axon terminals.
• When the stimulus occurs, there are 2 options:
• Neuron fires if there is a large enough stimulus
• Neuron does not fire if the stimulus is too small.
• “All or none” response – neuron either fires or it doesn’t.
• If neuron fires, impulse travels to other neurons across synapse by release of neurotransmitters.
Name: ___________________________________ Date: ____________ Class: ______
Page 6/9
The Nervous System (CNS and PNS)
What is the Nervous System?
 The nervous system is a complex network of cells that communicate with
one another
 It controls mental and physical activity and contributes to homeostasis
Two Main Parts:
 Central Nervous System (CNS)
o Made of the brain and spinal cord
o 3 major divisions of the brain
o Cerebrum
 Has right and left hemispheres
 Right: recognition of faces, spatial relations
 Left: understanding of words, grammar, structure of
language
 Body’s left side is controlled by the
right side of the cerebrum and the
right side is controlled by left.
o Cerebellum
 Controls balance, movement,
posture, and coordination
o Brainstem
 Connects brain to spinal cord
 Controls reflexes
 Regulates heart beat, breathing,
and digestion
 Aides in balance & blood pressure
 Made up of the:
 Midbrain
 Pons
 Medulla Oblongata
 Peripheral Nervous System (PNS)
o Made up of all of the nerves
o Contains the Autonomic Nervous System, which regulates involuntary functions (digestion, heartbeat,
glands, etc.)
 ANS is made up of the:
 Sympathetic NS: controls body during emergency or major stress (“fight or flight”), and
during intense activities that consume energy (running, taking a difficult exam, etc.)

Parasympathetic NS: controls body during normal conditions, calms body and returns it
to regular maintenance functions
Name: ___________________________________ Date: ____________ Class: ______
Page 7/9
Name: _________________________________ Date: __________________ Class: _______
Parts of the brain and their functions
Identify which part of the brain controls each of the following functions:
Cerebrum Cerebellum Brainstem Hypothalamus
Controls logical thinking
Filters information going to / from brain
Regulates body temperature
Evaluates body positioning
Controls breathing
Regulates hunger
Controls language
Coordinates body movements
Controls creative thoughts
Regulates sleep
Name: ___________________________________ Date: ____________ Class: ______
Page 8/9
28.3 – The PNS carries information to and from the CNS
Use your textbook to find the answers to the following questions:
1.
What are the two divisions of the PNS?
2. What are the functions of the two sets of sensory neurons in the Peripheral Nervous System?
3. What does the motor division of the Peripheral Nervous System do?
4. What are the two systems that are part of the motor division of the PNS and what is the job of
each?
5. Draw a diagram below that relates ONLY the following five terms: Somatic nervous system,
sensory division, autonomic nervous system, motor division, peripheral nervous system
6. List five actions within the body that the autonomic nervous system controls.
Name: ___________________________________ Date: ____________ Class: ______
Page 9/9
28.4 – The CNS integrates nervous information
Use your textbook to find the answers to the following questions:
7. What are the two structures that make up the CNS?
8. What are the three jobs of the spinal cord?
9. What is the largest part of the brain?
10. The left side of the brain controls movement of the ______________ side of the body, and it
specializes in _________________________________________, ____________________________________,
and ___________________________________.
11. The right side of the brain controls movement of the ______________ side of the body, and it is
responsible for ____________________________________, and ___________________________________.
12. The two brain hemispheres are connected by a thick band called the:
13. The cerebrum is divided into many lobes that have different functions. What are three things that
the brain controls?
14. What does the cerebrum do?
15. What does the brainstem regulate and control?
16. What does the hypothalamus do?