Nervous System Objectives
• Identify structures of the nervous system.
• Explaining differences in the function of the
peripheral nervous system and the central
nervous system
• • Labeling parts of sensory organs, including
the eye, ear, tongue, and skin receptors
• • Recognizing diseases and disorders of the
nervous system
• Examples: Parkinson's disease, meningitis
Do Now: Monday, Nov. 3
• Objective: Nervous System
• Do Now:
1. Name at least 3 purposes of the nervous
system (what does it do/why do we need it?)
2. Name at least 3 parts of the nervous system.
1. Deals with sensory info: sight, sound, touch,
taste, smell
2. How does it work?
- Receives sensory info (hands, eyes…)
- Sends info via nerves
- Processes info in brain
- Responds through muscles
Nervous System in Action
3. Example: TOUCH
Receives  sends  processes  responds
Hand: HOT!
Arm nerves
Brain
Touch: HOT!
Nervous System in Action
4. Example: TASTE
Receives  sends  processes  responds
Taste,
Mouth
waters
Nervous System in Action
5. Example: SIGHT
Receives  sends  processes  responds
Slam on
brakes
Nervous System in Action
6. Example: SOUND
Receives  sends  processes  responds
Nervous System in Action
7. Example: SMELL
Receives  sends  processes  responds
NS is Divided into two parts:
1) Central NS
a. Brain and spinal cord
b. Processes info
2) Peripheral NS
a. Nerves, sense organs
b. Receives/sends info to
and from the body
Peripheral Nervous System
Divided into two parts:
1. Somatic Nervous System
a. Parts we consciously control
ex. Skeletal muscles
2. Autonomic Nervous system
a. Parts we don’t consciously control
ex. Smooth and cardiac muscles
Peripheral NS
Autonomic Nervous System
1. Sympathetic NS
a. Prepares us for action/energy use
ex. Example: Run from bear
2. Parasympathetic NS
a. Normal, resting state
ex. Example: breathing, digestion, etc.
Autonomic Nervous System
NS Graphic Organizer
Do Now: Tuesday, Nov. 4
• Objective: Types of Nerves/Reflex Arc
• Do Now:
1. What is the difference between the
autonomic and somatic nervous systems?
2. What two divisions make up the autonomic
nervous system?
Structure of a Neuron
Parts of a Neuron
• Neuron: cells of the nervous system
– Dendrite: sends info to cell body
– Soma/Cyton (cell body): gathers info and passes to
axon
– Axon: carries info from cell body
– Terminal buttons: send info to other neurons
Info Transmission
• Dendrite  soma  axon  terminal buttons 
next neuron
Synapses
• Synapse: gap between neurons that is used to
pass info from neuron to neuron
Reflex Arc
• Protection: quick decision to save body from
damage
• Speed: doesn’t involve brain to save time
• Uses 3 neurons
Reflex Arc Transmission
Sensory receptor  afferent (sensory) neuron  interneuron
 efferent (motor) neuron  effector (muscle)
Reflex Arc Parts
• Sensory receptor: receives sensory info
• Afferent neuron: transmits info to spinal cord
• Interneuron: quickly processes info in spinal cord
• Efferent neuron: sends response to muscle
• Effector muscle: receives impulse and reacts
Check for Understanding
• Why do we have reflex arcs (2 reasons)?
• How many neurons are involved in a reflex arc
and list them in order?
• What is a synapse?
• How is info transmitted from dendrite to the
next neuron?
Independent Practice
• Write a letter to a fifth grader explaining how
a reflex works in at least 5 COMPLETE
sentences.
• You are not allowed to use large words.
• You must explain the whole process in simple
terms a fifth grader will understand including
making analogies to real-world examples
(knee-jerk reflex, pulling your hand back from
a boiling pot, etc. )
Do Now: Tuesday, Nov. 4
• Objective: Major CNS Regions
• Do Now:
1. Draw a flow chart that describes a reflex arc
from receptor to effector.
2. What is the difference between an afferent
and efferent neuron?
Discussion
• What would happen if you injured your brain?
• Does it matter where it gets injured? Why or
why not?
Big Idea
• The brain is the main processing center of our
central nervous system.
• Understanding the modularity of the brain is
important not only in understanding how the
brain functions but also how it evolved and
how brain injuries impact individuals.
Vocabulary
•
•
•
•
•
•
Olfactory: smell
Auditory: hearing
Optical: sight
Thermo: heat
Amplify: to make larger or stronger
Chronic: reoccurring, constant
Part of the Brain Focus.
What do they control?
VOCABULARY:
• Olfactory
• Auditory
• Optical
• Thermo
• Amplify
• Chronic
MAJOR CNS REGIONS:
• Frontal
• Parietal
• Occipital
• Temporal
• Cerebrum
• Cerebellum
• Brain stem
• Spinal cord
Major CNS Regions
• Temporal: long-term memory, object
recognition, auditory information, speech
center
• Frontal: critical thinking, ranking reactions,
selecting appropriate responses
Major CNS Regions
• Occipital: vision
• Parietal: process sensory info from body (skin)
and spacial orientation (where things are
around them)
Major CNS Regions
• Cerebrum: frontal, temporal, occipital, frontal
• Cerebellum: takes in info on the position of
body parts and coordinates body movement
FG
FG
Major CNS Regions
• Brain Stem: reflexes, heart pumping,
breathing, smooth muscle contractions
• Spinal cord: conduct nerve impulses to and
from brain, spinal reflexes
Independent Practice
• Each station will discuss the symptoms of a
brain-injury patient. You need to diagnose
what region of the brain that individual
injured based on their symptoms.
• There will also be stations that mention an
area of the brain that has been injured and
you need to list two different problems they
would expect to see in those injured
individuals.
Last Slide for Friday, Nov 14
• Objective: Senses (Touch, taste, smell, pain)
• Do Now: What do the frontal, parietal,
temporal, and occipital lobes each control?
Wednesday-November 13,2014
Big Idea - Senses
• Sensory information comes at our bodies in
many forms. Knowing what types of receptors
our bodies have, what triggers them, and
where they are located is important to
understanding how to interact with the world
around us and why we perceive it the way we
do.
Introduction
• What are the main senses of the body?
• Where are the receptors for each sense?
Types of Sensory Receptors
• 1. Chemoreceptor: sense chemicals
• 2. Thermoreceptors: sense heat or cold (2
types)
Types of Sensory Receptors
• 3. Photoreceptors: sense light
• 4. Mechanoreceptors: sense pressure (many
types and vary on level of sensitivity)
• 5. Nociceptors: sense pain
Touch
• Most sensory receptors are in our skin.
• Touch is a combination of mechanoreceptors
and thermoreceptors.
Smell
• Olfactory receptors: hairs stick out that
respond to the shape of molecules in the air.
• Located high up in the nasal cavity (why we
breathe in deeply when we smell).
Taste
• Taste buds located all over tongue: sweet,
bitter, salty, sour, and umami.
• Taste hairs stick out and respond to shape of
food molecules to produce taste.
Taste Buds Regions
Pain
• Pain receptors are widely spread in skin and
tissues (except brain).
• Tissue damage stimulates them and they
persist for a long time.
Referred Pain
• Pain receptors on skin often share a pathway
to the brain with certain organs.
• Referred pain: leads to feelings of pain on the
skin when organs are damaged.
Referred Pain
Check for Understanding
• What type of receptors detect….
– 1. Pressure?
– 2. Pain?
– 3. Chemicals?
– 4. Temperature?
– 5. Light?
Check for Understanding
• 1. Where are most of the sensory receptors?
• 2. Why do we breathe in deeply when we try to
smell?
• 3. What are the 5 types of taste buds and
where are they located?
• 4. Where are pain receptors located?
• 5. What is referred pain and why does it occur?
Practice Questions
• Create FIVE multiple choice questions.
• Switch your questions with a partner and see
how many you can get write without your
notes.
• Discuss the questions you got wrong with the
writer.
Put both names on each sheet and hand in
when completed.
Example Questions:
1. What type of sensory organ processes smells?
a. Mechanoreceptors c. Thermoreceptors
b. Photoreceptors
d. Olfactory receptors
2. Which of the following is not a category of
taste buds:
a. Sweet
c. Bitter
b. Savory
d. Salty
Do Now: Friday., Nov. 14
• Objective: Structure of the Eye
• Do Now:
1. What are the five types of taste buds?
2. Where are most of the sensory receptors?
3. What type of receptors detect light, pain, and
temperature?
• How do you hear? Write down everything
that you know about how your ear works and
what is in it.
• Auditory Nerve-transfers auditory signals to
the brain
Parts of the Ear
• Outer Ear: collects sounds and funnels them
through the auditory system.
• Middle Ear: eardrum and bones that send
vibrations to the inner ear.
• Inner Ear: involved with hearing and balance.
Outer Ear
• Auricle (pinna) - outer ear
• External Auditory Meatus – external ear canal
Middle Ear
• Tympanic Membrane (eardrum): captures
sound waves
• Ossicles (malleus, incus, stapes) - transmit
vibrations and amplify the signal
• Eustachian tube - connects to throat and helps
maintain air pressure
Inner Ear
• Cochlea - turn the sound waves into signals for
the auditory nerves
• Semicircular canals - keep balance
• 1. Sound waves enter external auditory meatus
2. Eardrum vibrates
3. Auditory ossicles (malleus, incus, stapes) amplify vibrations
4. Stapes hits oval window and transmits vibrations to cochlea
5. Organs of corti contain receptor cells (hair cells) that
deform from vibrations
6. Impulses sent to the vestibulocochlear nerve
7. Auditory cortex of the temporal lobe interprets sensory
impulses
8. (Round window dissipates vibrations within the cochlea)
Eye Vocabulary
• Cornea: clear, front of eye where light enters
• Lens: focuses light that enters the eye
• Retina: light sensitive layer of eye that
contains eye cells
• Optic Nerve: takes visual info to brain
• Photoreceptor cells: cells that respond to light
Eye Structure
Astigmatism
• Description: Causes images to appear blurry
and stretched out because light strikes at
more than one location.
Astigmatism
• Causes:
– Cornea in normal eye curved like a basketball
– Cornea in astigmatism  like a football
Astigmatism
• Treatment:
– Eyeglasses or contacts
– Surgery to change shape of cornea
Myopia vs. Hyperopia
Myopia
• Description: AKA nearsightedness
– Close objects appear clearly
– Distant objects appear blurry
Hyperopia
• Description: AKA farsightedness
– Distant objects may be seen more clearly than
objects that are near.
Myopia
• Causes: images form in front of retina causing
blurry vision
– Cornea is to steep
Hyperopia
• Causes: images form behind retina causing
blurry vision
– Cornea is too flat
Myopia and Hyperopia
• Treatment: Eyeglasses, contacts, or surgery to
change shape of cornea.
Cataract
• Description: Gradual loss of the clarity of
visions, difficulty seeing contrasts (light/dark),
eventually loss of vision.
• Causes: Cloudy lens - caused by radiation,
diabetes, injury or advanced age.
Cataract
• Treatment: Surgery to remove the lens and
replace it with a plastic one.
Glaucoma
• Description: Gradual loss of vision and
sometimes with ocular (eye) pain.
• Causes: Increased pressure of fluids in eye
that damages optic nerve photoreceptor cells.
Glaucoma
• Treatment: Drugs or surgery (normal or laser)
to reduce eye pressure.