Hey everyone, this is my lesson plan on Nervous system for class 11. Please do drop in reviews as it would be great way to improvise my teaching organization skills through your valuable feedback.
1. Name - Madhuri P Reg No. - 1737907
Subject: Biology
Topic 6 – Physiology
Sub-topic – Nervous System
School: Class: IX
Time: 45mins
Teaching Points:
Definitions of resting potential and action potential.
Membrane potential – polarized, depolarized and repolarized
Transmission of nerve impulse along a non-myelinated neuron.
Instructional Objectives:
The students will be able to
Knowledge:
Define the terms – resting potential and action potential
Define the terms – polarized, depolarized and repolarized with respect to nerve impulse transmission.
Recall the function of sodium-potassium pumps.
Describe the transmission of nerve impulse.
Understanding
Differentiate between resting potential and action potential.
Identify and contrast polarised, depolarised and repolarised with respect to transmission of nerve impulse along a neuron.
Understands role of voltage-gated pumps in transmission of nerve impulse.
Summarize the transmission of nerve impulse.
Lesson No: 1 Date: 1st
January 2018
2. Name - Madhuri P Reg No. - 1737907
Application
Recall and apply the knowledge of transmission of nerve impulse for diagrammatic representation of the same.
Skill:
Draw the conduction of nerve impulse through the nerve fibre in a diagrammatic form.
Teaching Aids:
Black board work for flow-charts to categorize types of transport system across cell membrane – types of passive transport and
active transport and diagram of conduction of nerve impulse through a nerve fibre.
PowerPoint presentation for definitions with suitable images
Videos to show transport of Na+
and K+
ions across the membrane through pumps in PPT.
Animated pictures/ Gifs to show transmission of nerve impulse in PPT.
Previous knowledge Teachers activity Pupils activity
Introduction to nervous system Wishes the students Wish the teacher
Parts and function of nervous system Asks to name the parts of the nervous
system.
Respond with answer –
Parts are: Central nervous system and
peripheral nervous system.
Neuron – structure (motor neuron), types
and their function.
Statement of Aim: Students in today’s class we will be looking into the transmission of nerve impulse along a neuron, which is very
important for understanding the working of our nervous system.
3. Name - Madhuri P Reg No. - 1737907
Content Teaching
point
Teacher activity Student
activity
Evaluation
Resting potential –
The electrical potential across the plasma
membrane of a neuron, when it is not
conducting an impulse.
Resting
potential
Resting potential -
The time period when a neuron is not
conducting a nerve impulse, is called the resting
potential.
This membrane potential is due to an
imbalance of positive and negative charges
across the membrane
Sodium-potassium pumps - pump Na+ out of
the axon and K+ into the axon.
Three Na+ are pumped out of the neuron and
two K+ are pumped into the neuron - This
creates a concentration gradient of Na+ (outside
to in) and of K+ (inside to out)
The membrane is also much more permeable to
K+ as Na+, so K+ leaks back out of the neuron
through leak channels
This means the Na+ concentration is much
greater outside the neuron
There are also negatively charged ions
permanently located in the cytoplasm of the
neuron
These conditions create a resting membrane
potential of -70 mV inside the neuron
Observe
the
diagram
displaye
d on the
slide and
listen
carefully
.
Students
take
down
notes
and ask
doubts if
any.
What does the
minus sign
indicate in
resting
potential for a
neuron?
Answer –
The minus
sign indicates
that the inside
of the cell is
negative with
respect to the
surrounding
extracellular
fluid.
Action potential –
The reversal and restoration of the
electrical potential across the plasma
membrane of a neuron, as an electrical
Action
potential
Action potential –are rapid changes in
membrane potentials.
The arrival of an action potential caused by a
stimulus causes a depolarization (change from
Observe
the
diagram
displaye What ion
4. Name - Madhuri P Reg No. - 1737907
impulse passes along it (depolarization
and repolarization respectively). Action
potential
negative to positive when sodium diffuses into
the neuron) of the membrane as Na+ channels
begin to open.
If the membrane potential reaches a
threshold level of -50mV many more
voltage-gated Na+ channels open and Na+
rapidly diffuses into the neuron
The inside of the neuron becomes more
positively charged than the outside of the
neuron (depolarization)
K+ channels open and K+ ions diffuse out of
the neuron making the inside negative again
(repolarization - change from positive to
negative when potassium diffuse out of the
neuron)
d on the
slide and
listen
carefully
.
Students
take
down
notes
and ask
doubts if
any.
transport
signifies
depolarization
in neurons?
Answer –
transport of
Na+ ions into
the axon.
What type of
membrane
transport is
Na+
transport?
Answer –
Passive -
facilitated
diffusion.
5. Name - Madhuri P Reg No. - 1737907
Action
potential
After the action potential, there is a
refractory period where the impulse cannot
go back in the same direction. This ensures
a one-way nerve impulse
Types of membrane transport –
i. Passive transport – from region of
high to low concentration.
Types – diffusion and facilitated
diffusion.
ii. Action transport – from region of low
to high concentration with help of
energy ATP.
Observe
the
diagram
displaye
d on the
slide and
listen
carefully
.
Students
take
down
notes
and ask
doubts if
any.
6. Name - Madhuri P Reg No. - 1737907
Transmission of nerve impulse steps -
i. A part of the axon depolarizes
ii. Sodium diffuses from the adjacent
polarized region towards the
depolarized region – outside axon.
iii.The higher concentration of Na+
inside the depolarized region diffuses
towards the polarized (more negative)
region inside the axon
iv. The membrane potential of the
adjacent region becomes more
positive from -70mv to -50mV
(threshold potential).
v. This result in a depolarization in the
neighbouring region, as Na+ voltage-
gated channels open and Na+ diffuses
into the axon.
Transmissio
n of nerve
impulse steps
Transmission of nerve impulse steps:
Nerve impulses are action potentials
propagated along the axons of neurons.
Propagation of nerve impulses along the
axon results from the diffusion of Na+
ions from the area that was just
depolarized to the neighbouring area
that is still polarized inside the axon
When a part of the axon depolarizes, the
localized are inside the axon becomes
more positive as Na+ diffuses into the
axon through voltage gated channels
Outside the axon the concentration of
Na+ is less in the depolarized region, so
sodium diffuses from the polarized
region towards the depolarized region
The adjacent area inside the axon that is
still polarized (more negative)
The higher concentration of Na+ inside
the depolarized region diffuses towards
the polarized (more negative) region
inside the axon
These local currents cause the adjacent
region to become more positively
charged.
When this happens, the membrane
potential of the adjacent region becomes
more positive from -70mv to -50mV
(threshold potential)
This results in a depolarization in the
neighbouring region, as Na+ voltage-
Observe
the
diagram
displaye
d on the
slide and
listen
carefully
.
Students
take
down
notes
What type of
transport is
the Na-K
pump
associated
with in the
refractory
periods?
Answer –
Active
transport – as
Na+ ions are
pumped to a
region of high
positive
charge as K+
ions already
present -
repolarization
/ Na+ ions
present –
resting.
7. Name - Madhuri P Reg No. - 1737907
gated channels open and Na+ diffuses
into the axon
and ask
doubts if
any.
Concluding Statement: We shall conclude our class with this today. Next class we will be looking into the next topic – Synapses.
Recapitulation and Blackboard Summary:
Recapitulation Blackboard Summary
What is action and resting potential? Resting potential – The electrical potential across the plasma
membrane of a neuron, when it is not conducting an impulse.
Action potential – The reversal and restoration of the electrical
potential across the plasma membrane of a neuron, as an electrical
impulse passes along it (depolarization and repolarization
respectively).
What are the steps in transmission of the nerve impulse? Transmission of nerve impulse steps -
1. A part of the axon depolarizes.
2. Sodium diffuses from the adjacent polarized region
towards the depolarized region – outside axon.
3. The higher concentration of Na+ inside the depolarized
region diffuses towards the polarized (more negative)
region inside the axon
4. The membrane potential of the adjacent region becomes
more positive from -70mv to -50mV (threshold potential).
5. This result in a depolarization in the neighbouring region,
as Na+ voltage-gated channels open and Na+ diffuses into
the axon.
8. Name - Madhuri P Reg No. - 1737907
Evaluation:
Questions -
Depolarization is _________________________ type of
transport.
What potential state should be filled in the blank
space in the diagram B?
Which membrane potential is the neuron
associated with in A?
9. Name - Madhuri P Reg No. - 1737907
Answers:
Home assignment:
1. Summarize transmission of nerve impulse along with a nest diagram.
RESTING POTENTIAL
Polarised
Depolarization is ____Passive – facilitated diffusion_____
type of transport.