Transcript Action Potential Riddle Quiz

Week #3 (1/21 – 1/24)
Warm Up – Tues, 1/21:
- Review of Intro to NS
Anatomy Fun Fact:
As we grow older, the
brain loses a gram each
year.
Agenda:
1. Begin Action Potential notes
Pick up:
???
Have out:
???
Turn in:
Reflex Lab group
handouts (if not
turned in at the end
of last period)
Homework:
1.
Action Potential
Quiz – Fri, 1/24
Warm-up: Intro to NS
Review
• What organs are
included in the CNS?
• What are the 3 main
parts of a neuron?
• What is the function of
the dendrites? Cell
body? Axon?
• What does SNS stand for
& what kind of tissue
does it control?
• Are reflexes controlled
by the SNS
monosynaptic or
polysynaptic?
• Let’s play a game of “Telephone”! I’ll start by giving a message
to….
• In a Reflex Arc, what role are you & I playing (hint: it’s a tissue)?
▫ Neurons
• In anatomy, what is the space between each communicator
called?
▫ Synaptic cleft or synapse
• Was the message sent successfully?
▫ If not, why not?
How many parts were there to communicating the message?
1st: the person had to receive it (listening) – role of the dendrites of a neuron
2nd: the listener had to process the information (understanding the context of the
words) –
role of the
soma/cell body
3rd: the person
had to send the
message
(speaking/
sending it to the
next person) –
role of the axon
Understanding
• Information from one neuron flows to another neuron across a
synapse/synaptic cleft…
▫ a small gap separating
neurons that consists of:
 a presynaptic ending
(axon terminals) that
contains neurotransmitters
(NTs), mitochondria &
other organelles,
 a postsynaptic ending
(dendrites) that contains
receptor sites for NTs &
 a synaptic cleft or space
between the presynaptic
& postsynaptic endings.
BIOLOGY REVIEW:
What is the process of Diffusion?
• When it comes to understanding
how neurons communicate
(Action Potential or Nerve
Impulse), you must understand
how the process of diffusion
works!
▫ Diffusion Animation
▫ Particles move down their
concentration gradients (from
high to low)
• Is it an active or passive form of
transporting dissolves nutrients?
▫ Passive – NO ATP REQUIRED!
• Also known as “Nerve Impulses”
• Self-regenerating wave of
electrochemical activity that allows
neurons to carry a signal over a
distance (“game of telephone”)
• Pulse-like waves of voltage that
travel along several types of cell
membranes
• Analogy – assume students are POSITIVELYCHARGED Na & K IONS!
• Initiation/Resting Stage:
▫ Outside the classrooms (neuron) vs. inside classrooms (neuron)
▫ At 7:20 a.m., more students are arriving to school than are sitting
in a “0” hr class
▫ So the inside of the classrooms (neurons) have a “negative”
polarity.
• Initiation/Resting Stage:
▫ Some K+ channels are open: K+ diffusion occurring (out)
▫ Initiated by stimulus above a certain intensity or threshold
(~-70mV – resting potential)
▫ Could be a pin prick, light, heat, sound or an electrical disturbance
in another part of the neuron (“telephone call”)
▫ Electrical signal rises from changes in permeability of the
neuron’s axon membranes to
specific ions (Na+ & K+)
• Analogy – assume students are POSITIVELYCHARGED Na & K IONS!
 Depolarization (Rising Phase):
▫ Outside the classrooms vs. inside classrooms
▫ First bell rings & students move from the
halls into the classrooms
▫ This gives the inside of the classroom
(neuron) a more “positive” polarity.
 Depolarization (Rising Phase)
 K+ Channel gates are closed
 Stimulus causes gate in the Na+ Channel to open
 High concentration of Na+ outside, Na+ diffuses into neuron
 Electrical potential changes to ~ +40 mV
• Analogy – assume students are POSITIVELY-CHARGED
Na & K IONS!
 Repolarization (Falling Phase):
▫ Outside the classrooms vs. inside classrooms
▫ Dismissal bell rings & students leave the
classroom & enter the halls
▫ This gives the inside of the classroom
(neuron) a “negative” polarity again.
 Repolarization (Falling Phase)
 Depolarization causes K+ Channel gates to immediately open &
Na+ Channels close
 K+ diffuses out of neuron
 Reestablishment of initial electrical potential
of ~-60 mV
 Refractory Period (Recovery Phase)
 Na+ & K+ Channels cannot be opened by a
stimulus
 Na+/K+ Pump actively (ATP required) pumps
Na+ out of & K+ into neuron (against/up their
concentration gradients)
 Reestablishment of ion distribution of
resting neuron
 This AP acts as stimulus to neighboring proteins
within neuron membrane & initiates AP in
another part of neuron
 Wave of APs travel from dendrites to axon
terminals
 At axon terminal, electrical impulse is converted
to a chemical signal (neurotransmitter)
Week #3 (1/21 – 1/24)
Warm Up – Wed, 1/22 & Thurs, 1/23:
- Analyzing the Change in Impulse
Anatomy Fun Fact:
At a given point of time,
only ~4% of the cells
(neurons) in the brain
are active, the rest are
kept in reserve.
Have out:
Reflex Lab handout
Pick up:
Analyzing the
Change in Impulse
wkst
- What kinds of diagnostic
imaging are these pictures?
Agenda:
1. Getting the Message across the Synapse
2. Neuron/Action Potential Model-building
Homework:
1.
Action Potential
Quiz – Fri, 1/24
Action Potential
animation
• Getting the message
across (the synapse)?
▫ At axon terminal, chemical
signal (NT) crosses synapse
between adjacent neurons
 Starts AP on this neuron
▫ This activates Ca2+ channel to open
 Ca2+ diffuses into neuron
 Causes NT vesicles to move to end & fuse with cell membrane
 Through exocytosis, NTs are released into synapse
▫ NTs diffuse across synapse & bind to NT receptors on
another neuron
 Causes Na+ channels to open & AP is initiated in next neuron
Let’s Review…
How do neurons communicate?
• Action potential animation (~3 mins)
• What is another name for the nerve impulse that travels from
the cell body down the axon to the axon terminal?
• What happens in the Rising Phase/
Depolarization?
▫ Falling Phase/Repolarization?
▫ Recovery Phase/Refractory Phase?
• Once the AP has reached the axon
terminal, what ion entering the
neuron instigates the movement of
synaptic vesicles to the cell
membrane?
• What do the vesicles release into
the synapse?
Action Potential/Neuron
Model
• You will be divided into 4 groups to create 4 different
Neuron models!
• You will be presented with various materials you may
choose to use for your model.
• Each group will develop a model of a neuron, including:
▫ Dendrites
▫ Axon
- Cell body (soma)
- Synaptic terminal (axon terminal)
• Your neuron will also demonstrate the transmission of:
▫ Action potential
- Neurotransmitters
• You will be demonstrating your model to the class on Fri, 1/24
(before Quiz on Action Potentials)!
• Return any unused materials to where you found them!
• Do NOT waste materials…all materials were bought by me!
Action Potential/Neuron Model
• Each model of a neuron has to include:
▫
▫
▫
▫
Dendrites
Cell body (soma)
Axon
Synaptic terminal (axon terminal)
• Your neuron will also demonstrate the
transmission of:
▫ Action potential
▫ Neurotransmitters
Week #3 (1/21 – 1/24)
Warm Up – Fri, 1/24:
- Neuron Models Demo
Have out:
Neuron models
Anatomy Fun Fact:
Neurons, which are the
largest cells in the human
body, do not undergo the
process of mitosis.
- Why is this important to know?
Agenda:
1. Action Potential Quiz
2. Ch. 14 Tour (Brain)
Homework:
1.
Ch. 14 Tour - ???
Action Potential Riddle
Quiz
Questions from the Synaptic Potentials & NTs Review?
You may use your Synaptic Potentials & NTs Review as a
resource while you take your Riddle Quiz today!
Please take out 1 piece of notebook paper & label it “Action
Potential Riddle Quiz”. Write your NAME, DATE & PERIOD in
the top right!
For the 10 questions of the quiz, you will see screens for 30
secs. with “riddles” about Action Potentials.
Write JUST THE ANSWER to the riddle next to the number (do
NOT have to write complete sentences)!
When finished, turn your paper OVER so that NO ANSWERS
are showing!
Action Potential Riddle
Quiz
Riddle #1
A bright light just flashed in my
eye! If I am an Action Potential
traveling along the axon of a
sensory neuron, where am I
headed next (which organ)?
Action Potential Riddle
Quiz
Riddle #2
I am the space between the
neurotransmitters leaving one
neuron & the dendrites of an
adjacent neuron where the
message will be passed on.
Where am I?
Action Potential Riddle
Quiz
Riddle #3
I act as the insulation for the
electrochemical impulses that
travel the axon from the soma to
the next neuron. What am I
called?
Action Potential Riddle
Quiz
Riddle #4
Since there is a high concentration of me
outside the neuron, I am the ion that
diffuses into the neuron during the
Depolarization Phase of an Action
Potential after membrane voltage
threshold has been instigated by an
outside stimulus. What ion am I?
Action Potential Riddle
Quiz
Riddle #5
After the Refractory Phase of an
Action Potential within the axon of a
neuron, I re-establish the ion
distribution & ~-70 mV of a resting
neuron. Who am I?
Action Potential Riddle
Quiz
Riddle #6
At the axon terminal, I’m the kind of
impulse that allows for the release
of chemical neurotransmitters (to
pass the message along).
Action Potential Riddle
Quiz
Riddle #7
I’m the ion that starts it all at the
presynaptic ending!!! As soon as my
channel opens, I diffuse into the axon
terminal. I tell the synaptic vesicles to
head toward the cell membrane to let
their contents into the synapse through
exocytosis so the message can be
passed to the next neuron.
Action Potential Riddle
Quiz
Riddle #8
I’m the crazy hair-like projections
that take in the incoming
information during a “neuron
phone call”.
Action Potential Riddle
Quiz
Riddle #9
I’m the passive process by which
dissolved Na+ & K+ ions move
through chemical gates from an
area of higher concentration to an
region of lower concentration.
Action Potential Riddle
Quiz
Riddle #10
At the end of Depolarization &
beginning of Repolarization, two
things happen simultaneously.
I am those 2 things! Be specific!
Action Potential Riddle
Quiz ANSWERS
Riddle #1
A bright light just flashed in my eye! If I am an Action Potential
traveling along the axon of a sensory neuron within a
monosynaptic reflex, where am I headed next (which organ)?
Spinal cord OR brain
1 pt
Riddle #2
I am the space between the neurotransmitters leaving one neuron
and the dendrites of an adjacent neuron where the message will
be passed on. Where am I?
Synapse OR synaptic cleft
1 pt
Action Potential Riddle
Quiz ANSWERS
Riddle #3
I act as the insulation for the electrochemical impulses that
travel the axon from the soma to the next neuron. What
am I called?
Myelin sheath
1 pt
Riddle #4
Since there is a high concentration of me outside the neuron,
I am the ion that diffuses into the neuron during the
Depolarization Phase of an Action Potential after
membrane voltage threshold has been instigated by an
outside stimulus. What ion am I?
Na+ (sodium)
1 pt
Action Potential Riddle
Quiz ANSWERS
Riddle #5
After the Refractory Phase of an Action Potential within the
axon of a neuron, I re-establish the ion distribution & ~70 mV
of a resting neuron. Who am I?
Na+/K+ Pump
1 pt
Riddle #6
At the axon terminal, I’m the kind of impulse that allows for the
release of chemical neurotransmitters (to pass the message
along).
Electrical impulse/Action Potential/Nerve impulse
1 pt
Action Potential Riddle
Quiz ANSWERS
Riddle #7
I’m the ion that starts it all at the presynaptic ending!!! As soon as
my channel opens, I diffuse into the axon terminal. I tell the
synaptic vesicles to head toward the cell membrane to let their
contents into the synapse through exocytosis so the message
can be passed to the next neuron.
Ca2+ (calcium ions)
1 pt
Riddle #8
I’m the crazy hair-like projections that take in the incoming
information during a “neuron phone call”.
Dendrites
1 pt
Action Potential Riddle
Quiz ANSWERS
Riddle #9
I’m the passive process by which dissolved Na+ & K+ ions
move through chemical gates from an area of higher
concentration to an region of lower concentration.
Diffusion
1 pt
Riddle #10
At the end of Depolarization & beginning of Repolarization,
two things happen simultaneously. I am those 2 things! Be
specific!
Na+ channels close & K+ channel open
2 pts
Action Potential Riddle
Quiz ANSWERS
Put the NUMBER CORRECT over
11 pts & return to its OWNER!!!
Now turn them in the Hmwk Bin!