Biology
Unit - 2
Content and coordination
Biology
Syllabus Coverage
Unit 2 - Content and coordination
S
CORE
EXTENSION
Y
2
Organisms respond to changes in
the environment
L
2
Coordination in plants
L
2
Plant movements (tropic and
nastic movements)
A
B
U
S
2
Demonstration of responses of
plant parts to various stimuli
2
Plant Hormones (Phytohormones)
2
Photoperiodism
2
Human brain and its functions
2
Role of cholinesterase insecticides
and "nerve gas"
2
Brain diseases and EEG as an
important tool
2
Sense organs and their functions
2
Diseases of the endocrine system
2
Coordination in animals
2
Nervous system in animals
2
Reflex actions, involuntary and
voluntary actions
2
Human Nervous system
2
Chemical coordination in
animals
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SCOPE DOCUMENT
UNIT 2: Content and Coordination
In the earlier lessons, students have studied that the body of all living organisms is
made up of cells. These cells aggregate and differentiate to form tissues and
assembly of different tissues forms different organs. The various organs perform
their functions at the right time so that they can work together efficiently. Therefore,
some form of control is needed to coordinate their functions. For example, when we
eat food, our eyes help in locating the food, our nose senses the food, our hand
brings the food to our mouth and our jaw muscles help the teeth to chew the food.All
these activities occur in a coordinated manner, and if any of these activities misses or
does not occur in time then the body will not get nutrition.
In case of animals, including man, the chemicals produced by ductless (endocrine)
glands also bring about coordination. This coordination by chemicals is brought
about by the endocrine system. On the other hand the nervous system consists of a
series of nerve cells throughout the body. Signals from one part of the body are
transmitted to another part through these nerve cells.
Learning outcomes - Foundation
At the end of this unit, students should be able to :
2
Recognize the need for control and co-ordination in the body of various
organisms
2
Describe the methods of co-ordination in plants and animals.
2
Learn about various types of movements that occur in plants
2
List various plant hormones and discuss about their functions
2
Relate nervous system and endocrine system with the function of control and
coordination
2
Recognise sense organs as gateways for receiving information from the
environment
2
Recall nerve cell as the basic structural and functional unit of nervous system
and explain the terms synapse and nerve
2
Define nerve impulse
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2
Identify the components of central nervous system and explain what is grey
matter and white matter
2
Describe the location and structure of spinal cord and recognise its function
relating to reflex action
2
Draw an outline diagram of human body and show the location of various
endocrine glands
2
List the hormones secreted by pituitary, thyroid and pancreas
2
Give a brief idea of feedback mechanism in hormonal activity
Learning outcomes - Extension
At the end of this unit, students should be able to :
2
Describe the major regions of human brain and list their functions
2
Summarize the direct actions of the brain and spinal cord on controlling:
odetection of environmental change
v
consciousness
v
learning and memory
v
emotions
v
movement
2
Summarize what we know about cholinesterase insecticides and "nerve gas"
2
Brain diseases can turn out be devastating
2
Brain waves can be detected by the technique called EEG
2
Name the parts of the eye and explain vision in simple terms
2
Explain accommodation of the eye and give reasons for short sightedness
(myopia), long sightedness (hypermetropia) and their correction
2
Explain the structure and working of the ear
2
Describe various ways of taking care of sense organs;
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2
State the symptoms and cause of cretinism, goitre and diabetes mellitus
Cross Curricular Links
English:
2
Vocabulary builds up
2
Story writing on how different areas in brain coordinate with each other
Arts:
2
Prepare model and cut outs of Brain and different endocrine glands.
2
Jig saw of brain
Maths:
2
Case studies and data analysis
ICT:
2
Powerpoints
2
Animations
History:
2
Discovery of Hormones.
Geography:
2
Occurrence of disorders in various geographical areas
Music:
Song on Hormones
Ductless glands that are within
They are called the endocrine
Make chemicals that flow within;
And work with the nervous system
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Hormones, hormones
Chemical messengers are what you call the hormones
Each gland produces one or more hormones
With names that end with “...ins" and "...ones"
Cortisone, testosterone are just two of the hormones
Hormones, hormones
Estrogen, progesterone are two more of the hormones
Adrenal makes adrenaline
Fight or flight that comes from them
Pancreas makes insulin
Milk begins with prolactin
Hormones, hormones
The quantity is so tiny but you need all your hormones
Thyroid and the ovaries
Pituitary and the testes
All the glands they do secrete directly in the bloodstream
Hormones, hormones
Stimulate body functions:
The duty of your hormones
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LESSON TEMPLATE : CONTENT AND COORDINATION
Steps to be
followed
Teacher's Activity
Student's Activity
Warm up
Organisms
respond to
changes in the
environment
The teacher will put up questions Students will together have a
before students:
peer group discussion on
How are the various activities of whether organisms show
bodies of various organisms similar or different responses
regulated in response to other in accordance to their body
structures.
individuals and environment?
The teacher would, then, explain Worksheet 1a
how control and co-ordination (or Worksheet 1b
response to stimuli) helps the
living organisms to survive in the
changing conditions of
environment around them.
Activity 1a: Concept of Stimulus
Activity 1b: Responding to
Balancing Challenges
Activity 1c: Responses to Abiotic
Factors in an Ecosystem
Pre Content
Stimulus
The teacher would start her
session by explaining that any
change in the environment to
which an organism responds and
reacts is called stimuli.
Students will conclude from
the day's session that response
to stimuli is a characteristic
property of the living
organisms.
She would take an example of They also understand that
amoeba to explain the concept of both plants and animals react
to the various stimuli around
stimuli.
them. The method of reacting
Activity 2: Organisms react to
to the stimuli is different and it
various stimuli
is usually in the form of some
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http://www.youtube.com/watc movement of their body part.
h?v=7pR7TNzJ_pA
Worksheet 2
Content
Co-ordination in
plants
Comparing plants and animals,
the teacher would explain that as
plants do not have a nervous
system and sense organs like
animals have, they can still sense
changes in the environment.
The teacher would further go in
the depth of this topic and
explain that animals use both
nervous system and hormones
for co-ordination of various
activities. Whereas, growth and
other processes in plants are
controlled by plant growth
substances also called plant
hormones/phytohormones.
The changes in the environment
are sensed by the plants by moving
part of their body, instead of whole
body (as is the case of animals).
The teacher would them explain
the role of various types of plant
hormones in detail.
Activity 3:
Phytohormones
(Plant Growth substances)
Plants respond to
stimuli
In her next session, the teacher
would emphasize that plant
movements are largely brought
about by definite internal and
external stimuli.
She might ask her students:
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Students will try to list the
various uses of plant
hormones.
They discuss that certain
chemical substances are being
manufactured which closely
resembles natural phytohormones and may be
employed to control aspects of
growth and development.
They will in few groups collect
the information for following
artificial substances
a.
Artificial auxins
b.
Weed killer 2,4D
Some of them will also find the
role of hormones in plant
tissue culture.
Worksheet 3
Students understand that
most of the plant movements
usually occur due to unequal
growth of plant tissues in two
regions, which is also as a
result of phyto-hormones.
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What type of movements do they Further, they will recapitulate
know that happen in plants, in what was taught by their
teacher. They discuss among
response to external stimuli?
She would explain the difference themselves that the direction
between tropic and nastic of plant movements is
determined by the external
movements.
stimuli.
She would further explain positive
and negative tropism. Students Students will together prepare
might be given handouts in order a collage of 'tropism - a
to explain five common stimuli directional movement' using
that plants are exposed in the various cut out pictures.
environment. These are light,
gravity, chemicals, water and They will form three groups
touch. She would explain in detail and advised by the teacher,
about two types of tropisms and prepare projects on the
encourage students to prepare a remaining three tropisms that
project on the remaining three.
were introduced in the class.
Co-ordination in
animals
Activity 4 : Tropic movements in Worksheet 4
plants
The teacher would begin the After completing the session,
the students will be able to
session by telling her students That unlike plants, control and co- Recognize the need for control
ordination in animals is brought and co-ordination in the body
of animals
about by two systems (a)
Nervous System and
Identify the organs and
in
She would first explain the s y s t e m i n v o l v e d
nervous system in multicellular controlling and coordinating
animals, taking an example of various body functions
Get an overall view of
hydra.
N e x t s h e w o u l d e n l i g h t e n Nervous system in animals
(b)
Endocrine System.
students with divisions of Worksheet 5a
vertebrate nervous system giving Worksheet 5b
an insight into human nervous
system.
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Activity 5a:
Animals
Coordination in
Activity 5b: Nervous system and
endocrine system in animals
Human Nervous
System
The human nervous system
would be explained in detail,
emphasizing on the neuron structure and function.
The student will be able to...
1. Understand that nerve cell
is the basic structural and
functional unit of nervous
She would check the knowledge of system
her students:
2.. Identify the two main
(a)
Whether they know that types of neurons that are
neuron is the unit of nervous found in the peripheral
nervous system.
system?
(b)
Structure,
function and 3. Understand significance of
nervous system in human
arrangement of neuron
body.
Types of neurons
(c)
(d)
(e)
(f)
4. Understand how are
neurons able to transmit nerve
How are nerve impulses
impulses from one part of the
transferred from one neuron
body to another to another in the nervous
The Propagation of a Nerve
system?
Impulse
How do nerve impulses
Worksheet 6a
travel through the synapse.
Nerve impulses
Students would be encouraged to
compare the human nervous Worksheet 6b
system to that of functioning of a Worksheet 6c
school.
Activity 6a: Introduction to
Human Nervous System
Activity 6b: Nerve Cell the basic
unit of nervous system
Activity 6c: Transmission of
nerve impulses
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Organs of the
Nervous system
The teacher would go further in
her discussion of human nervous
system in explaining the various
organs that are present.
The student will try to
recapitulate what was taught
in the class
They will form groups to
The main organs of the nervous identify the components of the
system are: brain, spinal cord and central nervous system. Also
discuss the peripheral
nerves.
She would explain, in detail the nervous system
central and peripheral nervous They will also discuss the
system. Brief insight about the functions of the four main
human brain would also be given. parts (cerebrum, cerebellum,
She would explain reflex action brain stem, and
and reflex arc and then cite the hypothalamus) of the brain.
difference between a reflex action
and walking.
Worksheet 7a
Activity 7a: CNS and PNS
Worksheet 7b
Activity 7b: Significance of Worksheet 7c
Nervous System
Activity 7c: Reflex Action
Activity 7d: Synapse
Activity 7e : Concept of Action
Potential
Chemical coordination in
animals
The teacher would explain that
hormones are chemical
messengers that regulate the
biological processes in animals
also.
Next she would explain
characteristics and release of
various hormones.
Students will be able to relate
the changes in their body and
emotionally with the
hormones.
They will try to compare the
messages passed by nervous
and endocrine system
They will also understand the
structure and functions of
She might ask the students..
(a) How does the endocrine various endocrine glands,
system co-ordinate our body more particularly role of
activities?
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(b)
How do the endocrine t h y r o i d g l a n d a n d t h e
system and the nervous en doc rin e an d ex oc r i ne
function of pancreas
system work together?
What is the difference Worksheet 8a
between endocrine and
exocrine glands?
Worksheet 8b
The teacher would then discuss
the major hormones produced by
Worksheet 8c
the human body and their
functions.
(c)
Activity 8a : Role of hormones
Activity 8b : Exocrine and
endocrine glands
Activity 8c : Feedback mechanism
of hormone action
Post Content
Photoperiodism in
plants
The teacher would explain the
concept of photoperiodism in her
class. She would enlighten her
students with the role of a special
pigment, phytochrome.
Studnets are able to
understand that many
flowering plants use a
photoreceptor protein, such
as phytochrome or
cryptochrome, to sense
seasonal changes in night
length, or photoperiod,
which they take as signals to
flower.
She would explain how plant
hormones and phytochrome
pigment together are involved in
the control and co-ordination
between environment and plant
Worksheet 9
responses.
Activity 9: Regulation of
photoperiodism
Brain : Structure
and function of its
parts
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The teacher would go in the details
of structure of brain and various
functions that are performed by its
parts.
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Through the activities that
were performed in the class,
the students understand that
the brain is the highest coordinating centre in the body.
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She would encourage her students
to create a nervous system model,
working in pairs. Further, she
would ask them to act the roles of
various parts of the nervous
system.
Activity 10 : Human Brain
They will list the various
functions performed by the
brain.
Together they will have an
open house discussion about
the structure and function of
spinal cord.
Next they will try to find the
function of nerve gas
Worksheet 10
EEG as an
important tool
The teacher would discuss an The students will understand..
important tool to detect brain That most commonly EEG is
disorders.
used to show the type and
S h e w o u l d e x p l a i n t h a t location of the activity in the
Electroencephalogram (EEG) is a brain during a seizure.
measure of brain waves. It is a It also is used to evaluate
readily available test that provides people who are having
evidence of how the brain problems associated with
functions over time.
brain function.
The teacher would enlighten with
the fact that Scientists first
captured and recorded brain
waves in dogs in 1912. By the 1950s
the EEG was used commonly
throughout the World.
Students will list the problems
that can be evaluated using
EEG.
The teacher would finally tell
students that our senses make us
aware of changes in our
Students will explore the role
of other sense organs.
These problems might include
confusion, coma, tumors,
long-term difficulties with
The teacher would encourage her thinking or memory, or
students to watch a video in order weakening of specific parts of
to further understand about EEG. the body (such as weakness
Activity 11 : EEG as an important associated with a stroke).
tool
Worksheet 11
Sense Organs
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They understand that as in
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environment and in our own
bodies.
eyes, the ears convert the
sound energy (in vibrations)
She would further explain that we into nerve impulses.
have sense cells which actually They further discuss that
respond to stimuli. The special when a receptor responds to a
property of these sensory cells and stimulus, it sends the nerve
sense organs is that they are able to impulse to the brain, which
convert one form of energy to makes us aware of the
another.
sensation.
She would emphasize that the
structures which can do this are Worksheet 12 : Hand outs
called energy transducers.
She would explain how eyes can
convert light energy into electrical
energy of nerve impulse.
Activity 12: Structure and
Function of The Human Eye
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ACTIVITY 1A : CONCEPT OF STIMULUS
Learning Outcome:
The students would understand the concept of stimulus and its corresponding
response.
Content:
One characteristic that distinguishes living organisms from nonliving things is the
ability to sense and respond to conditions or changes in the environment. Any
substance or condition in the environment that causes an organism to react is called a
stimulus. The reaction of the organism to a stimulus is called a response. Living
organisms are able to sense and adjust to a variety of stimuli in the environment using
special sensory receptors that help them detect changes in light, odor, sound, and
textures. Sensory receptors can be as simple as the sensory cells in jellyfish that are
connected in a net-like arrangement, or as complex as the sensory organs in humans,
such as eyes, ears, or a nose.
Work with your group to complete two of the three activities that will further your
understanding of how organisms respond to the stimuli in their environments.
Activity:
Exploring the concepts of stimulus and response
The students would work in the group of 4, make a list of other things that serve as a
stimulus, and beside that word or phrase, write the response they might expect.
Each of the students should show an example on your whiteboard.
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ACTIVITY 1B: RESPONDING TO BALANCING CHALLENGES
Problem: Can you remain balanced for 30 seconds while standing on one foot?
Procedures:
1.
Place a piece of tape or sticky note on the floor.
2.
Take turns having one volunteer at a time try the following challenges while the
rest of the group observes the event.
Challenges (30 seconds each)
Balance w/ one foot on the tape and both eyes open
2
Balance w/ one foot on the tape and both eyes shut
2
2
Balance w/ one foot on the tape, eyes open, and arms held tightly against
your side
2
Slowly spin around 4 times, and then balance with one foot on the tape w/
eyes open
2
Slowly spin around 4 times, and then balance with one foot on the tape w/
eyes shut
3.
Record the answers to the following 3 questions.
1.
What did you observe as the volunteer tried to maintain a balanced position?
2.
What actions did the person take to recover his or her balance?
3.
Which challenge was most difficult? Why?
Student Activity : A Delicate Balance
Read and discuss the following passage.
Have you ever watched a gymnast walk on a balance beam? With each step, the
gymnast must make small balancing movements similar to the ones that you made
when balancing on the piece of tape. Years of training and practice help the gymnast
make very small balancing movements to avoid large over corrections that might cause
a loss of balance. This allows the gymnast to give a smooth, balanced performance.
The semicircular canals in our inner ears contain tiny hairs that help us maintain
balance or equilibrium. Gravity plays an important role in balance. The tiny hairs can be
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moved by fluid as it is pulled downward by the force of gravity when our head changes
position quickly. Nerves carry the message from the hairs to the brain, which causes the
body to react and regain balance. This might cause a dizzy or spinning sensation,
especially when sight is not being used to help the body as it maintains balance.
Most living things thrive in a balanced environment, and can tolerate a very narrow
range of changes in their external environment without suffering harm or death. In
order to survive, living things must constantly make adjustments to keep internal
conditions constant and balanced, in spite of changes that occur in the external
environment. For example, when warm-blooded animals are in cold temperatures,
they may respond by shivering to increase body temperature by muscle movement.
They also may develop "goose bumps" by making hair stick out straight to trap a layer
of air for insulation. In extremely hot temperatures, animals may respond by sweating
or panting to cool off. These responses automatically occur when body temperatures
rise above or fall below the animal's most favorable temperature range.
Plants have different types of response than animals, because plants have different
needs. Light is one of the most important abiotic factors in a plant's environment
because it is needed for photosynthesis. Plants have special growth chemicals that will
cause a plant to grow toward light, even if it causes stems to have a sideways growth.
Many animals, including humans, also respond to light. Work with your group to
conduct the following investigation.
Problem: How do human eyes respond to varying amounts of light?
Procedure:
1.
Position a flashlight so that the light shines toward a volunteer, but not directly
into his or her eyes. Observe the volunteer's eyes as he or she looks toward and
away from the light.
2.
Trade positions so that the volunteer can make observations of someone else's eyes
as they respond to light.
Questions:
1.
Describe the response of the volunteer's eyes to the light.
2.
What is the relationship between the amount of light and the pupil size?
3.
Why does the eye respond to light in this way?
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ACTIVITY 1C: RESPONSES TO ABIOTIC FACTORS IN AN
ECOSYSTEM
Place a check mark in the box that best represents the stimulus for each response listed.
Be prepared to justify and share your results with the class.
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WORKSHEET 1A
Directions: Answer the following questions.
1. A stimulus is
A.
something that causes a stimulus
B.
something that starts to respond
C.
something that causes a response
D.
something that starts a stimulus
2. A response is
A.
the reaction caused by a stimulus
B.
the reaction to an event
C.
the reaction to an occurrence
D.
all of the above
3. A waste treatment plant is located near a bayou, which houses many types of flying
fish. The plant receives a majority of its water from the bayou. During warmer months,
the amount of flying fish decreases by 6%. Which of the following provides a
reasonable stimulus for the decrease in flying fish population in the bayou?
A.
The flying fish don't like the loud sounds of the machines in the waste treatment
plant.
B.
More water is used by consumers during warmer months, which decreases the
amount of water the flying fish can live in.
C.
Less water is filtered by the water treatment plant during warmer months,
allowing the fish to travel upstream.
D.
None of the above are reasonable stimuli.
4. Match the stimulus on the right with the corresponding response on the left:
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Stimulus
Response
I.
The wind blows.
A.
My dog barks at the mail man.
II.
The mail man comes in my yard.
B.
I answer the phone.
III. A cat hears a can opener.
C.
The students raise their hands.
IV. A phone rings.
D.
A tree limb falls down
V. The teacher asks a question.
E.
The cat runs into the kitchen.
Resource: http://teachhouston.uh.edu/
ACTIVITY - 2 : ORGANISMS REACT TO VARIOUS STIMULI
Learning Outcome : Students will be able to understand that (a)
Response to stimuli is a characteristic property of the living organisms.
(b)
both plants and animals react to the various stimuli around them.
(c)
The method of reacting to the stimuli is different and it is usually in the form of
some movement of their body part.
Content :
The scientific name of the most commonly found Amoeba is Amoeba proteus. It
belongs to the domain Eukaryota and kingdom Protista. It is classified under the
phylum Plasmodroma and order Amoebida. Amoeba has a typical shapeless structure
and its movement depends on its changing body structure. Amoeba movement takes
place by change in the nature of cytoplasm and formation of peculiar structures known
as pseudopodia.
Characteristics of Amoeba
Amoebas are uni-nucleated, unicellular species. They are sometimes visible through
naked eye while few species are too small to be seen with naked eyes. Few species are
approximately grape sized. They respire by passive diffusion through their porous
bodies. Most amoebas are free pond water species. They can be freshwater or marine.
They have an adaptive mechanism called osmoregulation. The contractile vacoules
present inside their body help maintain osmotic balance (they store the excess water
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and diffuse it through the pores, thus their bodies do not burst due to hypotonicity)
when they are found in freshwater. Amoebas are heterotrophic in nature and they
ingest food by the mechanism of phagocytosis.
Amoeba Movement
The movement of amoeba is governed by a scientific theory known as Sol-Gel theory.
Amoeboid movement is dependent on its anatomy. The cytoplasm inside the cell is
capable of changing into different forms i.e. from fluid to solid and vice versa. When the
cytoplasm is in fluid state, it is known as plasmasol and the more solid or gel like state is
called the plasmagel. The interchange of plasmasol to plasmagel is known as Sol-Gel
theory and is responsible for amoeba movement.The amoeba propels itself when the
plasmasol flows through the center of the body towards its front and when it moves
towards the sides of the body, it becomes solid again. When the cytoplasm is in solid or
gel like state, there is no locomotion. Movement takes place only when the cytoplasm is
in fluid state. This way the amoeba "drags" itself and this movement is known as
amoeboid movement.
One more interesting fact about amoeba movement is the typical mechanism of
locomotion by formation of protuberances from their body known as peudopodium.
They are tentacle like extended structures meant not only for locomotion but also for
capturing prey. The number of peudopodia they form ranges from one to dozen. They
are also called false feet and can develop from any part of the body. The pseudopodium
grows and engulfs its prey by phagocytosis. They shrink when the process is over. They
also play a clever trick for capturing their prey by forming "blob". They form different
shapeless structures and engulf their prey. They are also capable of detecting an agile
organism or a slow moving specie.
From the above facts we come to know that amoeba movement is dependent on
changes in environment. Amoebas can detect sense of stimuli and respond to the
changes accordingly.
Students would be advised to share their views after having watched a video on
amoebic movements ‘http://www.youtube.com/watch?v=7pR7TNzJ_pA'
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WORKSHEET 2
A bright light shines into your eyes
2
stimulus: intensity of light
receptor: ______________________
transmission: neurons in CNS (brain)
effector: iris muscles
response: iris expands to reduce ______size, allowing less light to enter eye
You hear a sudden loud noise
2
stimulus: _______________________
receptor: mechanoreceptors (sensory neurons) in ears
transmission: neurons in CNS (brain)
effector: e.g. adrenal glands
response: adrenaline output increases ____________ (fight or flight-readiness for
emergency)
You stand on a sharp object
2
stimulus: pressure of sharp object
receptor: ________________
transmission: interneuron in CNS
effector: muscles in upper leg
response: ___________________
You are hungry and smell dinner cooking
2
stimulus: ________________ suspended in the air
receptor: chemoreceptors in lining of nasal passages
transmission: interneurons in CNS
effector: salivary glands
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response: release of _____________ into mouth cavity
2 ____________responses are automatic responses that occur rapidly and without
conscious thought. This nerve pathway is part of the sympathetic division of the
______________c nervous system. During a reflex response a ___________ triggers a
sensory neuron to send a nerve impulse to the __________________. The nerve impulse
is transmitted to an interneuron and then to a _________ neuron. The motor neuron
triggers a response in ___________ tissue.
3 _____________responses act to remove the body or part of the body from a potentially
dangerous situation, protecting it from further damage.
ACTIVITY - 3 : PHYTOHORMONES (PLANT GROWTH
SUBSTANCES)
Learning Outcome:
Students will be able to understand the function of various plant Hormones and their
effect on plants.
Content :
Ethylene is a hormone produced by most fruits; it is a colorless gas with the chemical
formula H2C=CH2 (the carbons are double-bonded). Ethylene is lighter than air, which
makes it diffuse rather rapidly. When a fruit is exposed to ethylene, it ripens at speeds
faster than it would without.
Student Activity 1 :
Materials Required :
6 unripe (green) bananas- In this case we will be using baby bananas
A large Ziploc™ plastic bag
Tincture of iodine-10% iodine dissolved in 90% ethyl alcohol Knife
Procedure :
1.
Make sure all bananas are about equally unripe by counting the number of
black/brown spots on the unripe banana. Make sure the bananas are not
excessively covered with spots or bruised.
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2.
Look at two of the green bananas. Count how many brown/black spots there are
that are larger than 2mm in diameter. Average the sums together and record the
calculation on the chart under "Number of Spots."
3.
Now, peel the two bananas. Take a knife and slice a small piece off the tops. Mash
them with a spoon until it's a paste; try to make sure there are no large chunks.
Now drip three drops of iodine onto each of the pastes. Roughly estimate what
percentage of the iodine reacted with the banana pastes; reacted iodine will turn a
dark blue or black color when introduced with ripe banana, while un-reacted
iodine will stay amber showing that the banana is unripe. Average the
percentages and put your results in the table. Also take note of any features of
interest. Then dispose of these bananas.
4.
Next, take a Ziploc™ bag. Place two bananas in it; seal it completely. Make one
puncture (using a knife or other sharp object) at the top of the bag. Do not rip the
bag. The puncture must not be too big (1-2mm wide). *This is to allow oxygen into
the bag, which is required for the reaction to take place, but to also prevent a large
amount of ethylene from escaping*Now, put it in an area that is well ventilated
and has moderate lighting.
5.
Now place two bananas in the same spot area as the bananas in the Ziploc Bag.
These are the controls, which will be in an environment with less ethylene.
6.
Leave the bananas in their environment for three days.
7.
Remove the bananas from their environment and perform the spot test and the
iodine test described above.
8.
Compare the results from the unripe bananas to the bananas left in the open and
the ones in the Ziploc Bag.
9.
Data Tables
Type of Banana
Unripe
In Open Space
Inside Ziploc Bag
Spots
Iodine Reaction
Other Notes
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Student Activity 2:
Content :
Charles Darwin in 1880 exposed seedlings to light and charted how they bent toward
the light only if the tips were exposed to light. He exposed grass to light and noted that it
curved toward the source. He covered the top of the seedlings with light proof caps, no
bending occurred. He wasn't quite sure what was going on.
Boysen-Jensen's study between 1910-1913 with beheaded seedlings, demonstrated that
placing a bit of gelatin on the stump, replacing the top on the gelatin, caused curvature
toward light to occur just as with intact seedlings. If the tip is not replaced, curvature
does not result.
Paal (1918) demonstrated that if a cut tip is replaced off center growth results and it will
be curved.
The reason for the bending of plants toward light is that growth hormones called
"auxins" on the non-illuminated side will cause the plant to grow more than on the
illuminated side. Since the elongated cells on the non-illuminated side will grow faster
than on the other side, the plant will bend. It looks as if the plant is moving toward light
to make food, but no plant can seek anything. The higher concentration of auxins on the
darker side stimulate growth. Growth responses resulting from external stimuli are
termed tropisms and since this has to do with light (photo=light) this is called
phototropism.
Procedure :
1.
In the first part of the lab, students will duplicate Darwin's and Boysen-Jensen's
experiment. They will utilize three similar seedlings. They need to cut the tips off
of two seedlings, cover the tip of one with a cap (have them experiment on how to
do this), leave the other plant with the cut top exposed, and leave the last seedling
as a control. Remind students how a "control" is used. A control represents what
will happen if nothing is done at all. This is used to compare whether an action has
an effect or if it is due to chance.
2.
In the second part of the lab, students will set up an experiment that determines
how long it takes different plants to "bend." They need a geranium, a seedling
(tomato, or other vegetable), and an ivy (using different plants are acceptable).
3.
Students will plant the rooted geranium and ivy in new containers and need to
place the plants in the same general area. Over the next week, they will observe
how the pants grow in light. The experiment will proceed quicker if you have an
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area of intense light that the plants will turn towards. They will notice that some
plants take longer to bend than others.
4.
Record your observations.
Procedure :
Exercise 1. Duplicate Darwin’s and Boysen-Jensen’s experiment as described by your
teacher. Describe what you did and record what happens on each day that
you observed the plant with and without a cap, and with no top.
__________________________________________________________________________
__________________________________________________________________________
__________________________________________________________________________
Day
Day
Day
Day
NO CAP
CAP
NO TOP
Exercise 2 : Plant rootings as described by your teacher. Make sure that you water the
plants and that they are all in the sample place. Describe how they bend for
one week.
DAY OF OBSERVATION
TYPE OF PLANT
1
2
3
4
5
6
7
CONCLUSIONS : Is there a difference amongst the plants?
__________________________________________________________________________
__________________________________________________________________________
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WORKSHEET : 3
1.
Name and describe the five major classes of plant hormones.
Class of Plant Hormone
Where it is made How it is transported
Responses it causes
2.
Define the term plant hormone.
3.
Provide an example of how a single aspect of growth and development may be
influenced by several hormones.
4.
Calcium influences several effects of plant hormones. Why, then, isn't calcium
considered a plant hormone?
5.
Provide an example for each of the following generalizations:
a.
A single plant hormone can produce many effects.
b.
The effects elicited by a hormone depend on many factors, including the
presence of other hormones.
c.
Hormonal responses probably result from changing ratios of hormones
rather than from the presence or absence of an individual hormone
6.
Gibberellins, cytokinins, and auxin all promote growth.
distinguish them from one another?
7.
What is the adaptive significance of increased ethylene production in response to
wounding and stress?
8.
Home gardeners commonly pinch off the shoot tips of certain plants in order to
promote fuller, bushier growth. Explain why removal of the shoot tip should
promote such growth.
9.
In what way is ethylene a unique plant hormone?
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10. What is phototropism and which hormone is involved in this phenomena? What is
the adaptive significance of phototropism?
11. Define photoperiodism and describe its adaptive significance.
12. What causes leaves to change color in the fall and senescence?
13. Describe structural and chemical changes that may occur in a plant as it begins
dormancy. What triggers this decrease in metabolism? What influences the
resumption of metabolic activity?
14. Many plants produce seeds that require a period of dormancy before they will
germinate. Of what value is the dormancy to the plant? Where might you expect
to find plants with seeds that do not undergo dormancy?
15. What is the adaptive significance of thigmomorphogenesis and gravitropism?
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ACTIVITY - 4 : TROPIC MOVEMENTS IN PLANTS
Learning Outcome: Students would understand the control mechanisms in plants.
Class Discussion: What happens when the leaves of a touch-me-not plant are touched?
When the leaves of a touch-me-not plant are touched, the plant uses electrical-chemical
means to convey this information from cell to cell.
Plant cells at the leaf base change their shape by changing the amount of water in them.
This results in folding and drooping of leaves.
Growth dependent movements or tropic movements are slow, occurring either
towards or away from the stimulus. The movement of plants in the direction of
stimulus is known as 'tr opis m'. Tropic movements are shown in response to
environmental factors such as light, gravity, water and chemicals. Plant roots are
positively geotropic and negatively phototropic whereas plant shoots are usually
negatively geotropic and positively phototropic. Pollen tubes show chemotropism by
growing towards the ovules.
Student Activity:
Skit: Students will prepare a skit to show different kind of tropism.
1.
Growth of tendrils: When a tendril comes in contact with a support, then the part
of the tendril away from the support grows more rapidly than the part of the
tendril that is in contact with the object, thus the tendril circles around the object
and appears to cling to it.
2.
Phototropism: Directional movement of a plant/plant part in response to light,
for example: shoots show positive phototropism.
3.
Geotropism: Directional movement of a plant/plant part in response to gravity,
for example: roots show positive geotropism.
4.
Chemotropism: Directional movement of a plant/plant part in response to
chemicals, for example- growth of the pollen tube towards the ovule.
5.
Hydrotropism: Movement of a part of a plant in response to water.
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Student Activity 2 :
Pair Share Activity: Discuss the tropic movement shown below:
____________________________________
____________________________________
____________________________________
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____________________________________
WORKSHEET 4
Q1.
How does phototropism occur in plants?
Q2.
How does chemical coordination occur in plants?
Q3.
What is the difference between the manner in which movement takes place in a
sensitive plant and the movement in our legs?
Q4.
Design an experiment to demonstrate hydrotropism.
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ACTIVITY 5A: COORDINATION IN ANIMALS
Learning outcomes: After completing the session, the students will be able to:
2
Recognize the need for control and co-ordination in the body of animals.
2
Identifies the organs and system involved in controlling and coordinating various
body functions.
2
Have an overall view of Nervous system.
Content:
The nervous system is a communications network that helps animals adjust to their
environment. The three main parts of the system are the brain, the spinal cord, and the
nerves. The brain can, at times, be compared to a computer in that it processes incoming
information, sends instructions back out through pathways. These pathways are the
nerves.
The brain is the processing center. It has three main parts:
1) the cerebrum, which is the largest,
2) the cerebellum, and
3) the medulla oblongata.
The spinal cord runs down the center of your back, is protected by the spinal column,
and contain 31 pairs of nerves coming out of each side. If a pathway of nerves is severed,
a part of the body will not receive a signal, and consequently will not work.
Nerve cells are called neurons. Nerve cells that move information to the brain are called
sensory nerves, while neurons that move information away from the brain are called
motor nerves. An action that takes place without thinking is called a reflex action.
Reflex and involuntary actions, such as heartbeat, are controlled by the autonomic
nervous system.
The main functions of the nervous system are to:
1)
control muscles and tissue,
2)
control organs,
3)
control senses, and
4)
control thinking
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Student Activity: A (3-5 minutes)
Introductory Attention-Getter :
I. Teacher will create a loud noise, without warning, causing students to exhibit
reflexes.
II. Students will be asked:
A.
What kind of reactions did you have? (eyes blinked, jumped out of seat, felt
heart skip a beat, etc.)
B.
Do you know what these involuntary reactions are called? (reflexes)
C.
What inside your body causes these involuntary reactions to occur? (nerves
or nerve impulses; nervous system)
D.
Why these involuntary reactions are important for living beings?
III.
Transition to lecture: "Reflexes are one important feature of the human
nervous system.
Student Activity B:
Activate the students with two different student activities - In the Hot Seat and
Technology Vocabulary Learning.
(1) In the Hot Seat - 5 minutes
Purpose: To motivate student learning
Description: In this activity, several students will be asked to sit in the "Hot Seat" and
answer questions related to the topic of study.
Q1.
What is the "control center" of the nervous system?
Q2.
What runs throughout your body and "tells" your muscles to move?
Q3.
Where is the "super highway" of nerves that comes from the brain located?
Q4.
What is the term for a movement that does not require thought?
Q5.
If you're in pain, those signals run from your nerves to where?
Technology Vocabulary Learning: Through classroom organization activity, the
teacher would explain the concept of human nervous system
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Cognitive Teaching Strategies
The teacher would give brief outline on parts of the nervous system, specifically
highlighting the new vocabulary. Vocabulary will include: brain, nerves, spinal
cord/column, cerebrum, cerebellum, medula oblongata, reflex, autonomic nervous
system.
Outline of lecture:
The nervous system is a communications network that helps animals adjust to their
environment. The three main parts of the system are the brain, the spinal cord, and the
nerves. The brain can, at times, be compared to a computer in that it processes
incoming information, sends instructions back out through pathways. These
pathways are your nerves.
The brain is the processing center. It has three main parts:
1) the cerebrum, which is the largest,
2) the cerebellum, and
3) the medulla oblongata.
The spinal cord runs down the center of your back, is protected by the spinal column,
and contain 31 pairs of nerves coming out of each side. If a pathway of nerves is
severed, a part of the body will not receive a signal, and consequently will not work.
Nerve cells are called neurons. Nerve cells that move information to the brain are
called sensory nerves, while neurons that move information away from the brain are
called motor nerves. An action that takes place without thinking is called a reflex
action. Reflex and involuntary actions, such as heartbeat, are controlled by the
autonomic nervous system.
The main functions of the nervous system are to:
1) control muscles and tissue,
2) control organs,
3) control senses, and
4) control thinking.
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Classroom organization: Students will be grouped into 4 groups of 3 students each.
There would be 5 stations set up throughout the room: Computer Central, the Human
Machine, Anatomy Study, Frankenstation, and Research Corner. The students will
spend roughly 15 minutes at each station. If a group or student finishes early, they may
go back to a station that was not completed, or browse Human Body reference
materials.
Explaining the center activities:
1.
Computer Central - Students will use a search engine, e.g., Yahooligans, to find
diagrams of the brain or nervous system. Once the students find an acceptable image,
they will copy and paste the image into a text box on a word document. These pictures
will be printed, cut out, and added to our body board. If they finish this activity, the
students will go to the website, "Your Gross and Cool Body," and read the information
on the nervous system.
2.
The Human Machine - This center is dedicated to hands-on activities and
experiments. Students will perform two experiments, one based on perception, the
other, sight. Both these experiments are given in the form of worksheets.
3.
Anatomy Study - Students will view diagrams from various expository texts in order
to draw and label a sketch of the human brain and spinal column. While at this station,
students will also label two index cards. Card one will contain an organ that is part of
this system, while card two will list the function of that organ. These cards will be
placed on the classroom body board.
4.
Frankenstation - Students are in the process of "cloning" themselves, by coloring
different body organs and adding them do an outline of their own bodies. This lesson
will find them coloring and adding a brain.
5.
Research Corner - Students will be given a 3 x 3 vocabulary worksheet with terms
related to the nervous system. They must make 6 sentences using the words provided,
by relating the three words across each row and down each column. Research
materials such as Research cards and expository texts will be provided, so that the
students can practice the skill of finding information through print media.
Summary Strategies
Brace Map
Students will complete a brace map on the parts and functions of the nervous system
(see Brace Map in Resources). The brace map is one member of an array of graphic
organizers called Thinking Maps. The Thinking Map series was developed by the
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Innovative Learning Group, 1995. The purpose of the brace map is to break down a
system from whole to parts, and the format for our map was created using Inspiration
Software.
Pictures of Displayed Information
Online resources:
http://its.guilford.k12.nc.us/act/grade7/act7.asp?ID=841
http://yucky.kids.discovery.com/body/
http://yahooligans.yahoo.com/science_and_nature/living_things/biology/Anato
my/m
http://www.google.com/image
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WORKSHEET-5A
Experiment 1
The Vanishing Ball - "Looking" at the optic nerve
1) In the center of the paper, draw two, round (6mm), colored dots 4 inches apart.
2) Hold the paper at arm's length from your face
3) Close your right eye and look at the dot on the right side with your open eye
4) Slowly move the paper toward your face. Be sure to concentrate on the right dot
and do not look at the one on the left
5) Stop moving the paper when the dot vanishes
Experiment 2 : Perception
1) Soak one pipe cleaner in the bowl with cold water, and soak the other in a bowl with
very warm water
2) Quickly remove the pipe cleaners, fit them together, and place them on the table.
Surprise!! What sensation did you feel?
WORKSHEET : 5B
Question: Label the major organs in the nervous system diagram.What is their function,
and how do they perform in relation to the rest of the Human Machine?
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WORKSHEET : 5C
3 x 3 Vocabulary - The Nervous System
Students will write six sentences, which illustrate the relationship between the words in
column 1 down, 2 down, 3 down, and rows 1 across, 2 across, and 3 across. In other
words, use all three words in the top row in the same sentence. Then, do this with the
other rows and columns.
cerebellum
medulla
oblongata
hemispheres
nerves
reflex
memory
muscles
spinal
cord
cerebru
Column 1 Down:____________________________________________________________
___________________________________________________________________________
Column 2 Down:____________________________________________________________
___________________________________________________________________________
Column 3 Down:____________________________________________________________
___________________________________________________________________________
Column 1 Across:___________________________________________________________
___________________________________________________________________________
Column 2 Across:___________________________________________________________
Column 3 Across:___________________________________________________________
___________________________________________________________________________
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WORKSHEET : 5D
Anatomy study- Draw and label a sketch of the human brain in the space provided.
Body Board:
1) On an index card, list an organ in this system that is not already present.
2) On a separate card, list a function of this system, and add it to our board.
WORKSHEET 5E : THE HUMAN MACHINE AT WORK (ACTIVITY)
Doctor's Diagnosis - Demonstrate the interdependence of systems through
writing. Describe an example of how your nervous system consciously and
unconsciously controls the organs of another body system. After describing your
examples, share them with the other group members.
ACTIVITY - 5B : NERVOUS SYSTEM AND ENDOCRINE SYSTEM IN
ANIMALS
Learning Outcome: The students will be able to compare the messages passed by
nervous and endocrine system
Nervous System vs. Endocrine System: Time of message delivery
The nervous system is much like a phone call. We dial in the number (which is the
'receptor' for who we want to talk to) and we get to deliver our message instantly to the
person.
The endocrine system is much like using the post office ('snail mail' as it is referred to in
this day). I will mail a letter to 'Julie Thompson' (Teachers..pick the name of a student in
class...this makes the example more apart of their world.) and in order to get this letter
to her, I must place her address on the envelope. The address is now the 'receptor' for
her house. I place the letter into the 'circulation' of all letters in the area. Her 'address'
helps the postal office find her house in a couple of days to deliver the message.
Now...much like the postal office's options of priority and express mail, the endocrine
system can also speed up delivery of certain messages based on importance.
The nervous system uses direct wiring (neurons) to communicate to the tissue and the
endocrine system uses chemical messengers (hormones) that use the blood circulation
to deliver their instructions.
Resource: www.tutorvista.com/.../endocrine-system.php
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WORKSHEET : 5B
1. Compare the regulatory mechanisms of the following system. Give the chemicals
involved in both.
Q5.
How do auxins promote the growth of tendril around a support?
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ACTIVITY 6A: INTRODUCTION TO HUMAN NERVOUS SYSTEM
Learning Objectives: The student will be able to understand the general organization
of the human nervous system.
Content :
In this unit, the students will understand the structure and functions of various organs
of the Nervous system. They would be able to have a comparative study of Nervous
system with an organization which would lead them to an understanding of Nervous
system as a complete system. The nervous system consists of the brain, the spinal cord,
and the network of nerves throughout the rest of the body. It is sometimes called the
master system, since it regulates and coordinates every other body system. The
nervous system provides a rapid means for the various parts of the body to
communicate with each other. It allows us to adjust to the world around us and cope
with the challenges of life. It influences how we act or react to stress. The fight or flight
response is a good example. This is a hormonally stimulated state to prepare the body
for an upcoming threat or challenge.
The nervous system is composed of two major parts; the central nervous system (CNS)
and the peripheral nervous system (PNS). The central system is the brain and spinal
cord, and is where most information is processed. The peripheral system is the network
of nerves throughout the rest of the body. The peripheral nervous system allows signals
to travel between the central nervous system and the body's sensory receptors and
motor effectors, such as the muscles.
1. The nervous system is an organ system containing a network of specialized cells
called neurons that coordinate the actions of an animal and transmit signals
between different parts.
2. The Central Nervous System (CNS) consists of the brain and spinal cord.
The Human Nervous System.
3. The CNS and PNS are anatomical divisions of the nervous system. The nervous
system is also divided into two physiological (or functional) divisions -- a voluntary
system, which as the name implies is concerned with voluntary actions such as
muscle movement; and an involuntary or automatic system referred to as the
autonomic nervous system
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Student Activity 1: Analogy
The students would do a comparative study of the Nervous system with an
organization/school. They would compare each part of the Nervous system,
understand its function and relate it with their study. They would also understand its
importance for cell survival. They can do the same in a group of two.
Teacher support: Brief information of the functions of organs of Nervous system
should be given to the students. An example is given below
The Nervous system is compared to a school
Organs of
Nervous system
Function
Department in school
Function
Brain
center of all
commands and
monitors all the
processes of the
body
Office of the
Principal
center of all
commands and
monitors all the
processes of the
school
Spinal chord
to relay all the
impulses,
information and
sensations to and
from all around
the body, to and
from the brain.
Vice Principal, Coordinators and
administrative
officers
To communicate all
information's to and
from the office to and
from all the stake
holders of the school.
Peripheral
Nervous System
information from
the body to the
spinal cord and
from the spinal
cord to the body
Wires of telephones
or messengers
Carry messages both
ways
Sensory neurons
providing the
CNS all the
information
regarding the
environment
Meetings with
students and staff
Helps to improvise
the teaching learning
process through
proper feedback of
students
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Motor Neurons
Help the body
react to different
environments
Circulars ,notices,
messages
To help office send
information to all
stakeholders
Muscles and
Glands
Site of action
Classrooms are the
area of activity
Teaching and
learning /transaction
Sense organs
help brain in
knowing more
about the external
factors.
Mail, calls, meetings,
complaints and
suggestions
To help office receive
Feedback from stake
holders
The students after completing the activity can come up by turns and present their
analogies. This can be followed by a brain storming session on classification of various
other departments/parts.
Student Activity 2: Students prepare a 3-D model of the nervous system on organs
using jelly, etc and demonstrate the importance of each.
Student Activity 3:
They can have a role play where they can enact one organ and present its function.
Teacher support: Students are made aware of the structure of all organs .
Student activity4 :
Group Activity : Students are divided into two groups. One group carries placards of
names of organs of Nervous system. The other group carries the functions they
perform. The students would be blindfolded and have to find their corresponding pair.
Teacher Support : The students need to have a prior knowledge of the functions of
organs.
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WORKSHEET : 6A
Answer the following
1.
List three ways the human brain is similar to a computer.
2.
List the four lobes of the brain.
3.
List a function of each of the four lobes of the brain.
4.
List the two major divisions of the nervous system and describe the difference
between the two.
5.
What are the three main functions of a nervous system?
Sensory Input, Integration, Motor Output
6.
What structures comprise the Central Nervous System (CNS)?
brain and spinal nerve cord in vertebrates
7.
Motor output is the conduction of signals from the ____CNS_________ to the
_____effector cells such as muscles_________.
8.
Signals are conducted by ____nerves_____________ which are bundles of
_____neurons_______ wrapped in connective tissue.
9.
Sensory and motor neurons are collectively called the ______peripheral nervous
system__.
10.
The structural and functional unit of the nervous system is the
_________neuron____________.
Answer the following long questions
How big is the human brain?
2
What are the organs of the Nervous system?
2
What does the brain do?
2
How long is the spinal cord?
2
How fast does the nervous system work?
2
What does the brain control?
2
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ACTIVITY 6B : NERVE CELL THE BASIC UNIT OF NERVOUS
SYSTEM
Learning outcomes: The student will be able to...
1.
Understand nerve cell as the basic structural and functional unit of nervous
system
2.
Identify the two main types of neurons found in the peripheral nervous system.
3.
How nerve cells are similar and different from other cells of the body
Content:
The Nerve Cell : The basic unit of the nervous system is the nerve cell, or neuron. The
basic function of the neuron is to transmit information. There are approximately 28
billion neurons in the human body penetrating every tissue and in every part.
Neurons vary greatly in size and shape, with the longest ones-those that extend
down the leg as part of the sciatic nerve-measuring over one meter. All nerve cells
have a similar structure.
The human body is made up of trillions of cells. Cells of the nervous system, called
nerve cells or neurons, are specialized to carry "messages" through an
electrochemical process. The human brain has approximately 100 billion neurons.
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Neurons come in many different shapes and sizes. Some of the smallest neurons
have cell bodies that are only 4 microns wide. Some of the biggest neurons have cell
bodies that are 100 microns wide. (Remember that 1 micron is equal to one
thousandth of a millimeter!).
Neurons are similar to other cells in the body because:
1.
Neurons are surrounded by a cell membrane.
2.
Neurons have a nucleus that contains genes.
3.
Neurons contain cytoplasm, mitochondria and other organelles.
4.
Neurons carry out basic cellular processes such as protein synthesis and energy
production.
However, neurons differ from other cells in the body because:
1.
Neurons have specialized extensions called dendrites and axons. Dendrites
bring information to the cell body and axons take information away from the
cell body.
2.
Neurons communicate with each other through an electrochemical process.
3.
Neurons contain some specialized structures (for example, synapses) and
chemicals (for example, neurotransmitters).
Student Activity 1 : A Simple Neuron Model
Here's the most simple model of a neuron I can think of...and you don't need any
supplies. It's your hand! Hold out your arm and spread your fingers. Your hand
represents the "cell body" (also called the "soma"); your fingers represent "dendrites"
bringing information to the cell body; your arm represents the "axon" taking
information away from the cell body.
Student Activity 2: Cooperative Learning Activity: (8-10 minutes)
I.
Students will assemble in groups of three
A.
One group member will be the recorder (write thoughts and ideas on paper)
B.
One group member will be speaker for the group in whole-class discussion
C.
One group member will be a "manager" (make sure things are moving along)
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II.
III.
Each group will be asked to...
A.
List 3 or 4 locations where sensory receptors can be found on or inside our
bodies (try to think of at least one that is not related to a sense organ). Possible
answers: on our skin-for temperature changes; all tissues and organs (except
brain)-for pain; on our muscles-for pressure and muscle
contraction/relaxation; taste buds on tongue; receptors (olfactory neurons) in
nose; receptors in ears.
B.
If sensory neurons carry nerve impulses from sensory receptors to the central
nervous system, what do you think motor neurons do? Answer: carry
information from central nervous system back to the muscle, gland, and/or
sense organ involved so it can respond to impulse delivered by sensory
neurons.
Whole-class discussion of students' responses
Transition to Activity 4:
"So basically, sensory receptors react to changes inside and outside of your body.
Internally they detect things like changes in blood pressure, pain, or strain on
muscles; externally they detect changes in light, sound, and temperature."
Student Activity 3 : Summary/Conclusion (15-20 minutes)
I.
Sensory and Motor Neurons: Partners in Transmitting Nerve Impulses (brief
review)
A.
Sensory - carry impulses from sensory receptors to CNS
B. Motor - carry information back to sensory receptors so muscles, glands, and
organs involved can react appropriately
C.
II.
Spinal cord - sensory nerves go into it and motor nerves come out
Reflexes: "Special" Responses
A.
Produce rapid, involuntary movement or response
1.
Important in times of danger
2.
Example: blinking of eyelid when insect approaches eye or when startled
by unexpected loud noise (like at beginning of class)
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B.
III.
Why are reflexes so fast?
1.
Involve few neurons
2.
Many reflexes never reach brain; travel only as far as spinal cord
3.
Example: blinking eyelid occurs before cerebrum is even aware of danger
Students exploring nervous system and mini-experiments on the Internet
A.
Students will work individually on computers in the computer lab
B.
Students will go to Neuroscience for Kids
(http://faculty.washington.edu/chudler/neurok.html)
C.
Students will be able to...
1.
Explore the entire human nervous system
2.
Test mini-experiments and activities about the nervous system
3.
Read current events dealing with neuroscience
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WORKSHEET : 6B
1)
Use the words from the list below to label the following diagram of a neuron in
the lines provided.
Word Bank Axon - Cell Body - Dendrites - Myelin
Node of Ranvier - Nucleus - Synaptic Terminal
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2)
Below is a list of different parts of a neuron. On the lines following each word,
write out what that structure does for the neuron (its function) and where it is
located on the neuron.
Axon:________________________________________________________________________
______________________________________________________________________________
Cell Body:_____________________________________________________________________
______________________________________________________________________________
Dendrites:____________________________________________________________________
______________________________________________________________________________
Myelin:_______________________________________________________________________
______________________________________________________________________________
Node of Ranvier:_______________________________________________________________
______________________________________________________________________________
Nucleus:______________________________________________________________________
______________________________________________________________________________
Synaptic Terminal:_____________________________________________________________
______________________________________________________________________________
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ACTIVITY 6C : TRANSMISSION OF NERVE IMPULSES
Learning Outcomes: The student will be able to...
2
Explain how neurons transmit nerve impulses from one part of the body to
another.
2
Understand the Propagation of a Nerve Impulse
Content:
Like many other cells of the body, neurons contain charged ions including
potassium, sodium and chlorine. Potassium and sodium are positively charged ions
whereas chlorine is a negatively charged ion. Unlike most other cells, neurons are able
to depolarize, creating a nerve impulse, by rapidly changing the concentration of ions
inside the cell relative to the outside of the cell.
When at rest, a neuron is polarized-that is, it has a negative charge on the inside of the
cell relative to the outside of the cell. This is because it has a higher concentration of
negatively charged ions on the inside. When stimulated, the nerve cell membrane
becomes permeable to sodium ions, which rush in temporarily causing a positive
charge to build up on the inside relative to the outside. For a short time afterward,
referred to as the "refractory period," the nerve cell is unable to "fire" again. A
mechanism in its cell membrane has to "pump" the sodium ions back out again,
restoring the negative charge and the "action potential" to the cell. Once the action
potential is restored the neuron is ready to transmit the next nerve impulse. This all
takes place in a very short period of time, measured in microseconds, as a single nerve
cell can fire hundreds of times during a single second.
Transmission of information in neurons
Dendrites receive messages from other cells axon fibers carry the impulse terminal
branches of the axon synapse with another neuron, muscle, or gland
2
A neuron fires an impulse when it receives stimulus from sense receptors
2
Stimulation by heat, light, pressure, or chemical messages from neighboring
neurons
2
Stimulation causes an increase of sodium (Na) into the cell, disrupting the cells
resting
Potential
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2
Stimulus can be: Excitatory- or Inhibitory2
Threshold of excitation- the point where stimulus creates an impulse
2
The impulse is known as an action potential
2
Action potential- is a brief electrical charge that travels down the axon
Neural impulse travels at speeds ranging from 2- 200 mph
2
Measured in milliseconds (1/1000 s) computer activity is measured in
nanoseconds
2
Myelin sheath- insulates the axons of some neurons and helps speed their
impulses
Multiple Sclerosis (MS) : A disease in which the myelin sheath degenerates,
causing a slowing of the all communication to muscles and the eventual loss of
muscle control
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Nerve Cells Communication
2
Scientist once believed that the branching axon of one cell fused with the
dendrites of another, uninterrupted
2
WE now know that the axon terminal of one neuron is in fact separated form the
receiving neuron by a gap, called synaptic gap. The junction itself is the synapse.
2
This gap is less than one millionth of an inch wide!! Whoa.
2
Also called, "protoplasmic kisses"…awe, so sweet.
2
When the AP reaches the knoblike structures at the end of the terminal branches
known as the __________________, it triggers the release of the chemical
messengers, called_____________________
Student Activity : 1
The nervous system (and how it communicates)
2
The structure and function of a neuron
2
Materials Required :
Teacher Materials
poster of a neuron
2
2
stopwatch
2
picture of a hand
2
picture of a brain
2
mousetrap
2
dominoes
2
children's literature on neurons/nervous system
Student Group Materials
2
neuron handout
2
rolling pins
2
different colored clay
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2
six labeled toothpick flags (reading nucleus, cell body, dendrites, axon, myelin
sheath, axon terminals; pre-made by teacher)
2
one button
2
one pipe cleaner
2
5 pieces of ziti macaroni
2
one piece of construction paper
Handouts
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Figure 1: A teacher guide and notes for the activity.
Figure 2: An individual student handout for the activity. This includes a diagram of a
neuron with defined parts in simple, easy to read language.
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Figure 3: A Barnes student constructs and labels his neuron!
Figure 4: A student's completed neuron.
Procedure :
2
The kids will be shown a diagram of a neuron. The teacher(s), will point out the
different parts and briefly describe what each part does. The teacher(s) will
explain how a neural impulse is transmitted to the brain using the example of a
hand touching a hot stove. (See Figure 1).
2
Then the kids will be given time to make their own neurons from different
colored clay. Using the pre-made "flag labels," they will label the different parts-cell body, nucleus, dendrites, axon, axon terminals, and myelin sheath. (See
Figures 3 and 4).
2
The teacher(s) will have set up an oval made from upright dominoes (with 1 foot
breaks in it). At one end will be a picture of the brain and at the other end will be a
picture of a hand. Starting at the picture of the hand, the kids will take turns
bumping the dominoes at each break to continue the dominoes falling as fast as
they can. (The falling dominoes represent a traveling neural impulse. See
"Domino Activity" Video). This part of the activity is timed with a stopwatch.
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After the kids have watched their "impulse" travel from the hand to the brain and
back the teacher(s) will discuss how long it took them to complete the activity
and compare that to how fast a real neural impulse is.
http://wikieducator.org/File:Teaching_bio_2.png
Student Activity 2 :
Lesson plan
Opening Questions
2
What is the nervous system? What does it do?
2
What is a neuron?
2
How do neurons work?
Activity
1.
Before activity begins, make six "flag labels" for each student (using one
toothpick and a small piece of white paper). The six labels should correspond
with the 6 parts to be focused on: cell body, nucleus, dendrites, axon, axon
terminals, and myelin sheath. Also before activity begins, set up domino
apparatus described above.
2.
Discuss the function of nervous systems-- to relay messages and control body
functions. Discuss the role of a neuron as a "little messenger" of the system.
3.
Show students the parts of a neuron (cell body, nucleus, dendrites, axon, axon
terminals, and myelin sheath) using the large neuron poster. Explain each part's
function. Show how a chemical message travels through a neuron.
4.
Hand out student materials (including individual handouts) and have students
construct their own neuron model. Clay is used to make the dendrites, cell body,
and axon terminals, pipe cleaner for axon, ziti for myelin sheath, and a button for
the nucleus. (See Figure 4).
5.
After models are completed, ask students to stand behind one section of the oval
domino apparatus.
6.
Place a picture of a brain on the tailed end of the oval and a picture of a hand on
another.
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7.
After snapping the mousetrap on the paper hand (a teacher task ONLY), instruct
one student to hit their row of dominoes as the stopwatch starts. Other students
follow suit (knocking down their own row of dominoes in the oval). Watch as
they fall around the table. (See "Domino Activity" Video).
8.
Repeat step 7 if desired.
9.
Ask students: How do the dominoes represent a message traveling through
neurons? If needed, explain the process being sure to incorporate the brain and
hand in the answer.
10. Clean up.
http://wikieducator.org/File:Little_messenger_handout.png
Wrap up comments/ Discussion Questions
2
Although our domino "message" seemed to travel fast, a real neuron can fire in 5
milliseconds. That's 200 times per second!
2
One neuron in the body can be connected to as many as 1000 other neurons.
2
Your brain alone has 100 billion neurons. And you have neurons everywhere in
your body!
2
What did we learn?
v
What does the nervous system do?
v
What are the "little messengers" of the nervous system? What are its parts
and what do they do?
2
Ask students for an example of how the nervous system works.
v
i.e. What happens when you step on a nail with your foot?
Linkages
Maths connections
We will use a stopwatch to time how long it takes for the kids to "send the message" as
fast as they can with the dominoes. Then, we will explain that in reality, it takes less
than a second. Neural impulses travel at speeds from 1 to 120 meters per second.
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Literature connections
Several books can be used alongside this activity for student reference. They are:
Your Wonderful Body! by Joyce Hurwitz and Roz Schanzer
Getting to Know the Amazing Human Body by David Macaulay
Dr. Frankenstein's Human Body Book by Richard Walker
If students finish their neuron model earlier than others, these books can be consulted.
They contain information on neurons and the nervous system in general.
WORKSHEET : 6C
Answer the following questions:
1.
All cells have an electrical charge difference across their plasma membrane
called the ____membrane potential_____________________________________.
2.
The membrane potential exists because:
the different concentration of certain ions across the cell membrane.
3.
The membrane potential of an unstimulated neuron is called the ____resting
membrane potential________________________.
4.
What makes invertebrates like squid and lobsters such good animals for the
study of nerve impulses?
they are large in diameter
5.
What is the principal + charged ion outside of a cell?
Na+
6.
What is the principal + charged ion inside of a cell?
K+
7.
How do these ions move across the cell membrane?
They must either be pumped by membrane proteins or by simple diffusion
through ion channels.
8.
In a neuron, an action potential can only be generated in the
_____axon_________________.
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9.
The action potential is a non-graded, all or non event; meaning ___magnitude of
the action potential is independent of the strength of the depolarizing
stimulus that produced it, providing the stimulus reached threshold
depolarization level___.
10. The action potential arises because the plasma membrane has ___voltage-gated
____ ion channels.
11. Which two types of voltage-gated ion channels contribute to the action potential?
Na+ and K+
12. Which voltage-gated ion channel opens first and which one opens second in an
action potential?
Na+ opens first and K+ opens second
ACTIVITY 7A : CNS AND PNS
Learning Outcomes: The student will be able to...
1.
Identify the components of the central nervous system and peripheral nervous
system.
2.
Explain the structure and functions of central nervous system
3.
List the two parts of the central nervous system and their basic functions.
4.
Discuss the functions of the four main parts of the brain.
Content:
The central nervous system is made up of the brain, spinal cord, and nerves. The brain
has three main parts, the brain stem or medulla, the cerebrum, and the cerebellum.
Each part has a special job to perform.
The medulla keeps your heartbeat and your breathing regular.
The cerebellum is in charge of balance and coordinating all of the muscles. The
medulla and cerebellum work all of the time, even when we don't know it.
The cerebrum controls thinking, moving and sensing. It is in control when youread a
book or play a game.
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The spinal cord is a long piece of nerve tissue that runs from the brain through the
backbone. It connects the brain to the body's nerves. Nerves are tiny fibers that are in
the spinal cord and throughout the entire body. Nerves pick up information and send
it up the spinal cord to the brain. Individual nerves are in charge of seeing, hearing,
smelling feeling, or touching something.
Certain nerves in the spine and brain tell parts of the body to act really fast. When the
body must act very fast in order to avoid injury, the message from the sensory nerves
doesn't go all the way to the brain before your body takes action. The message travels
from the sensory nerve to the spinal cord and is sent back to a muscle right away. This
quick action is called a reflex. A reflex is an action we take even before the brain
knows about it.
Organization of Human Nervous System
A.
B.
Central Nervous System (CNS)
1.
Brain and spinal cord
2.
Body's control center
a.
Organizes incoming information from sensory organs and receptors
b.
Issues outgoing commands to various parts of the body
3.
Connected to rest of body by nerves that make up the...
Peripheral Nervous System
1.
2.
Composed of sensory neurons and motor neurons
a.
Act as independent communications pathways
b.
Each monitors a different part of the body
Carries nerve impulses sent between CNS and rest of body
Central Nervous System
A. The brain and its four major parts
1.
Cerebrum
a.
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Wrinkled outer layer
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b.
B.
Handles most sophisticated functions of brain (processes visual
images, thinking, and planning)
2.
Cerebellum-essential for coordination of movement
3.
Brain stem-contains nerves that control vital life processes that are not
consciously controlled (breathing, digestion, heart rate, etc.)
4.
Hypothalamus
a.
Body's center for emotions and instincts such as pleasure, pain,
hunger, and thirst
b.
Maintains body's temperature and water balance
Spinal cord-cable of nerve tissue that extends from brain stem down the back
1.
Nerve impulses from body and brain run up and down it
2.
Important component in making reflexes occur
3.
Surrounded and protected by backbone
Peripheral Nervous System
A.
B.
Sensory neurons
1.
Carry nerve impulses from sense organs and receptors to CNS
2.
Also referred to as afferent neurons
Motor neurons
1.
Carry nerve impulses from CNS to muscles and glands
2.
Also referred to as efferent neurons
"There are many different kinds of sensory receptors in your body. For example, your
eyes, which are considered as sense organs, contain receptors called rods and cones. I
would like all of you to take a few minutes to think about the various places these
receptors are located throughout your body.”
Student Activities:
Assign students roles to be different parts of the central nervous system. Clear a large
area and have each student stand in the correct place for their part.
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Parts needed:
Brain - top of the classroom
Nerves - runners from the fingers and toes to the spinal column
Fingers
Toes
Spinal cord - runner from the nerves to the head
Explain how the central nervous system works. Then simplify it so the students so
that they can demonstrate it: normally the nerve sends the information to the spinal
cord, the spinal cord receives the information and sends it to the brain, the brain
makes a decision and gives the information to the spinal cord, the spinal cord sends
the information back to the nerves.
However, in an emergency, the nerves send the information to the spinal cord. It
recognizes the danger and makes an instant decision. The nerves carry out that
decision while the spinal cord sends the information to the brain. The brain then
assesses the situation and agrees with the decision or makes a new one.
Give the students different scenarios to act out. Have the spinal cord person decide if
he needs to make a decision or not. Scenarios could include:
touching a hot pan,
2
stepping on a tack on the carpet, and
2
2
something brushing against your leg in the dark.
Wrap Up:
For homework, have students write a story about their day as a spinal cord.
Encourage them to talk about the decisions they had to make and if those decisions
were right or wrong.
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WORKSHEET : 7A
Answer the following questions.
The nervous system is made up of the brain, spinal cord and .
How many main parts does the brain have?
one
2
two
2
three
2
Which part of the brain keeps your heartbeat and your breathing regular?
brain stem/medulla
2
cerebrum
2
cerebellum
2
Which part of the brain is in charge of balance and coordinating all the muscles?
brain stem/medulla
2
cerebrum
2
cerebellum
2
Which part of the brain is in charge if you are riding your bike?
Which part of the brain controls thinking, moving and sensing?
brain stem/medulla
2
cerebrum
2
cerebellum
2
The spinal cord connects the
to the body's nerves.
Which part of the brain is in control when you read a book or play a game?
brain stem/medulla
2
cerebrum
2
cerebellum
2
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Which part of the brain is in control when you are reading your favorite book?
The medulla and the
Individual
something.
work all of the time, even when we don't know it.
are in charge of seeing, hearing, smelling feeling, or touching
A quick action made by the body without the brain knowing about it is called a .
http://www.myschoolhouse.com/courses/O/1/34.as
(II) Label the diagram in the spaces provided with the correct name of each lobe of the
brain.
Word Bank
Frontal Lobe
Occipital Lobe
Parietal Lobe
Temporal Lobe
Describe the functions of the:
Frontal Lobe:_________________________________________________________
Occipital Lobe:_______________________________________________________
Parietal Lobe:________________________________________________________
Temporal Lobe:________________________________________________________
http://faculty.washington.edu/chudler/fillobe.html
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DIVISIONS OF THE NERVOUS SYSTEM - A REVIEW
WORD BANK
Hemispheres
hippocampus
cerebellum
brain
Amygdale
cortex
nerve
thalamus
Sulcus
Glia
tract
ganglia
Hypothalamus
neurons
gyrus
spinal cord
corpus callosum
nuclei
cerebral cortex
colliculi
________________________________________
Instructions: Complete the following sentences using words from the Word Bank.
1.
The Latin word meaning "bark" of a tree is used for the area of the brain called
the________________.
2.
The midbrain includes structures such as the superior and inferior __________
and red nucleus.
3.
A structure important for movement and balance is the ______________.
4.
The central nervous system is divided into two major parts: the ____________
and the __________.
5.
In the central nervous system, collections of neurons are called _____________.
6.
A bump or bulge on the cortex is called a __________and a groove is called a
_______________.
7.
One important function of the ________________________ is to control body
temperature.
8.
The brain contains about 100 billion ____________ and trillions of "support cells"
called __________.
9.
The limbic system is a group of structures that includes the
__________________________, the hippocampus, mammillary bodies and
cingulate gyrus.
10.
In the Peripheral Nervous System, a collection of axons is called a ___________.
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11.
The brain is divided into two halves called _______________________.
12.
In the peripheral nervous system, collections of neurons are called
______________.
13.
The _____________receives sensory information and relays this information to
the __________________.
14.
One part of the limbic system that is important for memory and learning is called
the ___________________.
15.
The right and left sides of the cerebral cortex are connected by a thick band of
nerve fibers called the ____________________________.
16.
In the central nervous system, collections of axons are called_______________.
http://faculty.washington.edu/chudler/fillobe.html
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ACTIVITY 7B: SIGNIFICANCE OF NERVOUS SYSTEM
Learning Outcome:
The student will be able to understand significance of nervous system in human body.
Materials Required :
3 chart papers folded, your writing instrument of choice, 3 pieces of poster board.
Problem:
How does the Nervous system relate to a modern day security system? What does each
part exactly relate to?
Procedure:
1.
In-groups of two, you will design brochures and advertise what I call the nervous
security system.
2.
The key feature is to give an overall sense of the organization and function of
nervous system. Tell how it acts as security system complete with sensors that tell
the body there is something wrong. You may use drawings, computer graphics,
photographs of actual organs, pictures from magazines, journals, or books to help
in your advertisement of each system. Let your imagination run WILD!
3.
You are to give your nervous security system a name.
4.
Your brochure must include the following vocabulary: cell body, dendrites,
neuron, axon, impulse, central nervous system, cerebellum, brain stem, spinal
cord and peripheral nervous system.
5.
Each group will orally present its brochure to the class.
http://www.teach-nology.com/worksheets/science/bio/lab8/
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WORKSHEET 7B
1.
What are the four main parts of a neuron?
Cell body, dendrites, axon, synaptic terminals
2.
The site of contact between a synaptic terminal of a neuron and a target, such as
another neuron, a muscle
cell, or a gland, is called a
______synapse____________________.
3.
What are the cells called that lie on each side of a synapse?
pre-synaptic cell and post-synaptic cell
4.
The simplest type of nerve circuit is termed a ______reflex arc_________________.
5.
What is the minimum number of neurons that can make up a "reflex arc", and what
would these neurons be?
2, there must be at least one sensory neuron and at least one motor neuron
6.
What are "interneurons"?
these are neurons within the CNS
7.
Interneurons are constantly __active___.
context for?
What does this active provide the
for interpreting sensory input and directing an appropriate response
8.
Ganglia and nuclei are collections of ______cell bodies of neurons______. How do
they differ from one another?
Ganglia are found in the peripheral nervous system while nuclei are found
within the brain.
9.
What cells form the insulating sheaths around axons? Where are these cells
found?
Schwann cells - outside the CNS, Oligodendrocytes - within the CNS
10. What two factors affect the speed at which an action potential travels down an
axon?
The diameter of the axon, the larger the diameter the faster the action potential
The presence of myelin around the axon, myelin insulates the axon and allows
the action potential to travel by "salutatory conduction".
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Write the number of matching statements before the words given in first column
_____ afferent neurons
1)
_____ autonomic nervous system
2) Potassium ions inside the plasma membrane
and sodium ions are outside.
_____ axon
3)
similar to the insulation of an electrical wire.
_____ central nervous system
4)
largest part of the brain
_____ cerebellum
5)
control of involuntary actions
_____ Cerebrum
6)
transmit impulses to the cell body of a neuron
_____ Dendrites
7)
comprised of the brain and spinal cord.
_____ Depolarization
8)
allows the control of skeletal muscles.
_____ efferent neurons
9)
similar to the body's "autopilot".
_____ Ganglion
10) indentations in the myelin
_____ Myelin
11) the membrane returns to its normal
orpolarized state.
_____ nodes of Ranvier
12) sodium gates open and sodium ions rush into
the neuron.
_____ Polarization
13) transmit impulses away from the CNS to an
effector.
____ Polarization
13) transmit impulses away from the CNS to an
effector.
_____ Repolarization
14) similar to a conductor in a electrical wire.
_____ somatic nervous system
15) a small gap between the presynaptic and
postsynaptic membranes.
_____ Synapse
16) those that take impulses toward the CNS
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bundles of cell bodies outside of the CNS.
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ACTIVITY 7C : REFLEX ACTION
Learning Outcomes: Students should be able to:
2
Explain how a voluntary reflex works
2
Explain how an involuntary reflex works
2
Describe the pathway of reflexes from cause to behavior
Content:
When the stimulation of a receptor results in a spontaneous, involuntary reaction, it is
called reflex action or simply reflex.
Reflexes are of two types:
2
Simple or unconditioned or natural reflex
2
Complex or conditioned reflex
Simple or Unconditioned or Natural Reflex
In this type of reflex, the brain is not involved. The receptor is stimulated which is
conducted to the spinal cord by the effector. The effector neuron from the spinal cord
conducts a response to the muscle or the gland. This causes an immediate reaction. It
does not involve any thinking or reasoning. It is a natural response and will occur even
in new-born babies. For example, blinking of eyes when strong light falls on the eyes.
Types of Simple Reflex
Simple reflex is also of two types. They
are as follows:
In the first type, only the sensory and
motor neurons of the spinal nerves are
involved.
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Jerking of knee when tapped below the kneecap is an example.
In the second type, the interneuron present in the spinal cord is also involved.
The moving away of hand in response to pin-prick or heat is an example of this type.
In the above diagrams, it can be seen that the pathway of conduction is in the form of
an arc. Thus, these pathways are also called the reflex arcs.
Know Something
Complex or Conditioned Reflex
This type of reflex involves the brain but it is also as fast as the simple reflex. Salivation
on smelling one's favourite food is an example of conditional reflex. The individual
recognises the smell and based on a previous experience, the response (salivation)
occurs. The recognition of the previous experience involves the association centres of
the brain. A series of experiments were conducted by Ivan Pavlov, a Russian biologist
which demonstrated conditioned reflex. He found that when a bell was rung every
time a dog was given food, the dog showed salivation only at the sound of the bell. The
ringing of the bell is called the conditioned stimulus. The dog had, thus, 'learnt' to
associate the sound of the bell to food and this made it salivate at the sound of the bell.
It can be represented as follows:
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Conditioning is the basis for learning. Learning to cycle or swim can be called a
conditional response.
Student Activity
Materials, Equipment, Set-up 2
4 rulers
2
neurological pathways poster
2
one whiteboard/chalkboard
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2
enough calculators for each student
2
data collection handout
Student Activity: (Enquiry Based )
Engagement (2 minutes)
2
While introducing the teaching team, drop a book or make some other loud
v
noise unexpectedly
What just happened?
v
How did you react? What kind of behaviors did you see?
v
Why does the body react that way?
v
Where did you learn to do that?
v
Do other animals do the same thing?
v
There are 2 different kinds of reflexes: voluntary and involuntary
v
Involuntary reactions are the ones you just experienced, ones you can't really
2
control. They go through the nerves without going to your brain.
Voluntary reflexes are ones that you have control over. The signal goes through
2
the brain to be processed.
Both take very different paths through the circulatory system.
2
Exploration (8 minutes)
2
Students will attempt to calculate their voluntary reaction time using a ruler.
v
In pairs the students will, one at a time, have their partner hold a ruler by the
highest number end just above their fingers which are held in a pinching
position. The fingers should not be touching the ruler. Without notice, the
partner drops the ruler and the student's goal is to grab the ruler as quickly as
possible. Students will do multiple trials and collect data on an Excel
spreadsheet. After averaging that data, reaction times will be discovered
using an existing. Each individual can graph their own reaction time as well
on a piece of paper to see if/where they plateau.
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2
Explanation ( 5 min)
v
First ask students what they discovered, and why they thought it happened?
v
Using an illustration, explain the pathway of the reflex again.
v
Ask students what the difference is between what they just did, and what the
doctor does to test their reflexes at the office.
v
Discuss the benefit of involuntary reflexes and why people react to a sudden
loud noise the way they do.
QuestionsAre your reflexes faster or slower if:
v
You know when the ruler is going to be dropped?
v
You aren't paying attention?
v
An object is hot?
v
You are scared? If faster, why?
2
Evaluation (3 min)
v
Draw the two different paths that reflexes take, both voluntary and
involuntary.
v
Name three types of voluntary reflexes, and three types of involuntary
reflexes.
v
How are we similar to animals you see outside when it comes to reflexes?
2
Elaboration (2 min)
v
What is the relationship between reflexes and age? Or gender? Allow the
students to collect data from the teaching team and compare it to their results.
v
If we did 100 trials instead of 10 would the results be any different? Why?
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v
Try the experiment again with your non-dominant hand. Is your reaction
time slower, faster or the same? Does it plateau at the same place?
A-Sensory Neuron
B-Motor Neuron
http://academic.kellogg.cc.mi.us/herbrandsonc/bio201
http://mooreslore.corante.com/archives/images/axon.GIF
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ACTIVITY 7D: SYNAPSE
Learning Outcomes:
At the end of this activity, students should be able to:
-explain that Nerve cells communicate with each other at a junction called a synapse
-structure and function of a synapse
- define a neurotransmitter.
Audio video Student Activity 1: How Neurotransmission Works
Nervous System-1.docx
http://science.education.nih.gov/supplements/nih2/addiction/activities/lesson2
_neurotransmission.htm
Student Activity 2
Conent :
The brain has one hundred billion neurons, more or less. They connect in a huge
network exchanging billions of signals per second with one another and with your
body. Neurons relay signals via the synapse, the tiny space between nerve cells.
When a synapse occurs, neurotransmitters flow from one neuron to the next. A
neurotransmitter is a chemical that relays the signal.
Neurons firing, synapses connecting, that's what the brain's all about. Nanobots are
intercepting the neurotransmitters that make the synapse work. (Note: Show
students synapse diagram on Lesson Handout.) Dr. Eric Chudler from the University
of Washington explains the neurotransmission process this way: "Communication of
information between neurons is accomplished by movement of chemicals across a
small gap called the synapse. Chemicals, called neurotransmitters, are released from
one neuron at the presynaptic nerve terminal. Neurotransmitters then cross the
synapse where they may be accepted by the next neuron at a specialized site called a
receptor. The action that follows activation of a receptor site may be either
depolarization (an excitatory postsynaptic potential) or hyperpolarization (an
inhibitory postsynaptic potential). A depolarization makes it MORE likely that an
action potential will fire; a hyperpolarization makes it LESS likely that an action
potential will fire.”
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Learning Outcomes:
Neurons convey information using electrical and chemical signals.
Student Activity: 1 - A Role Play
The students assume the role of sports reporters. They observe the role-playing
activity, read the informational writing, complete the game-diagram activity, and
play the Neuro Defender game. At the end of the lesson, students write a sports
report for the local newspaper. A metaphor for the process of transmitting
information from one cell to another can be found in our athletic games. For example,
it is much like the game of football or soccer, where a team tries to score points by
passing the ball to one of its members. The neurotransmitter is like the quarterback
throwing the pass to the wide receiver or the forward on a soccer team passing the ball
to a wing. The pass itself is like the synapse, where an idea or message is taken from
one side to the other. In the Neuro Defender game, the Nanobots are the opposing
team that tries to intercept the ball and stop the pass from the quarterback to the wide
receiver or from the forward to the wing.
Student Activity: 2 - Role Play a Football Game Diagram
Copy and give each student the attached activity Diagram #1, The "Pass", to
demonstrate the similarities between a football or soccer pass and the
neurotransmission process in the brain. Review the diagram with the students.
Divide the class into opposing teams. Assign a quarterback and a wide receiver from
one team. Ask the quarterback to throw a football to the wide receiver. The people on
the opposing team will try to intercept it.
Copy and give each student the activity Diagram #2, The Neurotransmission Process
in the Brain (no labels), to demonstrate the process of neurotransmission.
Ask the students to work in small groups of 3 or 4 to label the diagram. Diagram #3,
The Neurotransmission Process in the Brain (master with labels) is included for you
to use as a guide. This activity will serve as a content vocabulary study and a way to
transfer the student's prior knowledge of how a pass is used in a football game, which
is similar to how neurotransmission works in the brain.
Student Activity:3 Play the Neuro-Defender Game:
NeuroDefender Game Description
Nerve impulses are releasing neurotransmitters to help send messages to Agent
NM7's body so she can regain her balance in order to cross a dangerous chasm. These
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neurotransmitters are being launched into the synaptic cleft at nerve-ending
terminals, where a neuron's axon meets another neuron's dendrite. However, one
particular synaptic cleft has become a dangerous place for neurotransmitters. This
synaptic cleft is filled with nasty Nanobots, sent to robotize Agent NM7's brain and
stop the neurotransmitters from reaching their correct receptors. It's up to you to help
guide the neurotransmitters safely to their final destinations.
You have a limited amount of time to find each neurotransmitter's correct receptor
before the body takes over and sends in its own big guys, Acetylcholinestrase, to
destroy the well-meaning neurotransmitters. Once the player has successfully
docked all three neurotransmitters, the synapse fires. Agent NM7 regains her balance
and coordination and is able to cross the chasm.
Student Activity: 4 This is the movie screen script.
Use this to help build the students' background knowledge prior to playing the game.
Movie Script: Intro to NeuroDefender
Yeah, like I was saying, your brain's got a hundred billion neurons more or less. They
connect in a huge network exchanging billions of signals per second with one another
and with your body. The neuron's a busy little nerve cell. Neurons relay signals via
the synapse, the tiny space between to neurons. When a synapse occurs,
neurotransmitters flow from one neuron to the next. A neurotransmitter is a chemical
that relays the signal.
Neurons firing, synapses connecting, that's what the brain's all about. Here's a
synapse that's got all it going on. But the other synapse has issues, and guess who's to
blame. Nanobots are intercepting the neurotransmitters that make the synapse work.
Get in there and stop them!
Movie Script: NeuroDender Finale
2
You did it! The synapse is working again. Agent NM7 will
2
make it across the chasm!
Student Activity:5 Write a sports report that describes the process.
Ask students to assume the role of a sports reporter. They should play the
Neuromatrix game again and refer to their Diagram #2, The Neurotransmission
Process in the Brain.
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They can write a sports report about the neurotransmission process and include their
own drawings to illustrate the process. For example, students can write a "play-byplay" coverage report or a summary of the game. Ask students to share their sports
reports with the class or post them online on a class web site.
http://www.morphonix.com/docs/NeuroDefenders%20Lesson%20final2.pdf
Copyright © 2003 Nelson Chapter 9 How Nerve Signals Maintain Homeostasis
WORKSHEET : 7S
Label the diagram using the terms given below
presynaptic membrane
postsynaptic membrane
neurotransmitter substance
synaptic cleft
synaptic vesicle
receptor sites
mitochondria
Events of a Synaptic Transmission
Number these events in the correct order.
1………… (a) An action potential is stimulated at the postsynaptic membrane and
impulse travels down dendrite.
2 …………. (b) An enzyme cleaves the neurotransmitter substance and clears out
the synaptic cleft.
3 …………. (c) Impulse reaches synapse from the axon.
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4 …………. (d) Impulse stimulates synaptic vesicles to move to presynaptic
membrane.
5…………..(e) Neurotransmitter substance diffuses across the cleft.
6 …………. (f) Neurotransmitter substance fits into receptor sites on postsynaptic
membrane.
7………......(g) Synaptic vesicles dump neurotransmitter substance into synaptic
cleft.
http://chatt.hdsb.ca/~duncand/FOV1-000D8CF8/FOV1-000E9548/FOV1000E954E/synapse.pdf
ACTIVITY 7E : CONCEPT OF ACTION POTENTIAL
Learning Outcomes : The student will be able to
Turn your classroom into a giant synapse as students act out communication at the
neural level by behaving as pre-synaptic vesicles, neurotransmitters, postsynaptic
receptors, secondary messengers and re-uptake transporters. Neurotransmitters and
receptors interact via "lock-and key" puzzle pieces
Nerve cells communicate with each other at a junction called a synapse. When
stimulated by an action potential, a neuron releases neurotransmitters into the
synapse.
Receptors on the outside of the receiving cell (post synaptic cell) fi t synaptic
neurotransmitters similar to a "lock and key". Once neurotransmitters "lock" into the
appropriate receptor, a secondary messenger is released in the receiving cell.
After neurotransmitters have done their job, they are released from the receptors and
sent back through the cell through re-uptake transmitters. In the sending
cell,neurotransmitters are packaged in vesicles.
Materials Required
2
(2) 15-foot sections of rope or masking tape
2
Classroom set of Job Assignment Tags (included)
2
String for Job Assignment Tags
2
Neurotransmitter/Receptor complex puzzle pieces (included)
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CD or tape player, music
2
Basic neuron structure, neurons communicate using action potentials and
2
chemicals called neurotransmitters
Content:
Nerve cells communicate with each other at a junction called a synapse.
When stimulated by an action potential, a neuron releases neurotransmitters into the
synapse.
Receptors on the outside of the receiving cell (post synaptic cell) fi t synaptic
neurotransmitters similar to a "lock and key". Once neurotransmitters "lock" into the
appropriate receptor, a secondary messenger is released in the receiving cell.
After neurotransmitters have done their job, they are released from the receptors and
sent back through the cell through re-uptake transmitters.
In the sending cell, neurotransmitters are packaged in vesicles.
Teacher Action
1.
Place masking tape or rope on the fl oor of your classroom, hallway, basketball
court etc… to represent pre- and post- synaptic membranes. The membranes
need to be arranged in an area large enough for several of your students to move
back and forth from one side to the other comfortably.
2.
Review the structure of a neuron, including: cell body, nucleus, axon, synapse
and dendrites. Focus student's attention on the terminal end of the axon and the
synapse. Show Overhead A. Explain that this activity will focus on this area and
it's role in communication between neurons.
3.
Place Overhead B on top of Overhead A to show how student roles correlate
with structures in the synapse. Assign students their roles and give the students
the appropriate Job Assignment tag prepared
4.
Position the students around the membranes you've created on the fl oor
accordingly. Give the students who are dopamine neurotransmitters a
dopamine neurotransmitter puzzle half
5.
Give students who are dopamine receptors a dopamine receptor puzzle ha
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6.
The two students who are serotonin receptors should also be given a serotonin
receptor puzzle half There will be no complementary puzzle half for these. Print
Job Assignment tags, cut out, attach string to hang around the neck Print
Neurotransmitter and Receptor puzzle halves cut out and laminate.
Tip: Adjust the number of Job Assignments and puzzle halves to accommodate the
number of students in your classroom. We recommend starting with the
neurotransmitters, receptors and uptake transporters.
Preparation
For a group of 23
1Print Job Assignment tags, cut out, attach
string to hang around the neck (Teacher
Resource Pages 5-6)
Print Neurotransmitter and Receptor puzzle
halves (Teacher Resource Pages 1-4), cut
out and laminate.
Tip: Adjust the number of Job Assignments and
puzzle halves to accommodate the number of
students in your classroom. We recommend
starting with the neurotransmitters, receptors and
uptake transporters.
http://gslc.genetics.utah.edu/teachers
http://teach.genetics.utah.edu/content/addiction/JumpinTheGap.pdfhttp://teac
h.genetics.utah.edu/content/addiction/JumpinTheGap.pdf
1.
http://www.bioedonline.org/resources/files/4_BLCh_MessageInNeuron.pdf All
cells have a membrane potential; however, only certain cells such as
__neurons__________ and ____muscle cells_________ have the ability to generate
large changes in their membrane potential.
These cells are called
_____excitable_________________________.
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2.
What types of ion channels are present in the cell membrane? How are these channels
opened?
ungated channels and gated channels, ungated channels are always open while
gated channels are opened either by chemicals or by a threshold voltage
3.
What are the two different types of "graded potentials"?
hyperpolarization and depolarization
4.
Define each type of "graded potential". Tell which ion channel is involved in each
type of "graded potential".
hyperpolarization - a change in membrane potential so that the membrane
potential becomes more negative compared to resting membrane potential, K+ ion
channel
depolarization - a change in membrane potential so that the membrane potential
becomes less negative compared to resting membrane potential, Na+ ion channel
5.
Why are these voltage changes called "graded potentials"?
because the amount of hyperpolarization or depolarization depends upon the
strength of the stimulus
6.
If a sufficiently strong stimulus causes depolarization to reach "threshold potential" it
triggers a different type of response called an _____action potential________.
View Solution
Label the Brain Anatomy Diagram
Read the definitions below, then label the brain anatomy diagram.
Cerebellum - the part of the brain below
the back of the cerebrum. It regulates
balance, posture, movement, and muscle
coordination.
Parietal Lobe of the Cerebrum - the middle
lobe of each cerebral hemisphere between
the frontal and occipital lobes; it contains
important sensory centers (located at the
upper rear of the head).
Corpus Callosum - a large bundle of nerve
fibers that connect the left and right Pituitary Gland - a gland attached to the
cerebral hemispheres. In the lateral section, base of the brain (located between the Pons
it looks a bit like a "C" on its side.
and the Corpus Callosum) that secretes
hormones.
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Frontal Lobe of the Cerebrum - the top,
front regions of each of the cerebral
hemispheres. They are used for reasoning,
emotions, judgment, and voluntary
movement.
Pons - the part of the brainstem that joins the
hemispheres of the cerebellum and
connects the cerebrum with the cerebellum.
It is located just above the Medulla
Oblongata.
Medulla Oblongata - the lowest section of
the brainstem (at the top end of the spinal
cord); it controls automatic functions
including heartbeat, breathing, etc.
Spinal Cord - a thick bundle of nerve fibers
that runs from the base of the brain to the
hip area, running through the spine
(vertebrae).
Occipital Lobe of the Cerebrum - the
region at the back of each cerebral
hemisphere that contains the centers of
vision and reading ability (located at the
back of the head).
Temporal Lobe of the Cerebrum - the
region at the lower side of each cerebral
hemisphere; contains centers of hearing and
memory (located at the sides of the head).
Copyright ©2001-2010 EnchantedLearning.com ------ How to cite a web page
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ACTIVITY 8A : ROLE OF HORMONES
Learning Outcome:
Students will be able to relate the changes in their body and emotionally with the
hormones.
Activity:
Introduce the unit with this story. "You are cycling in a neighborhood park. Out of the
corner of your eye you see a large, vicious looking dog looking at you. He is growling,
barking and showing his teeth. Suddenly he breaks free from his leash and comes
straight toward you. Your heart begins to pound, your hands get sweaty and your
muscles tighten up. You grab your cycle and race to your parent's car. As you slam the
door, the dog jumps up against the window. You are safe now but your heart is still
pounding."
What do you think you would feel?
The students will write their experiences and feelings on a sheet of paper.
The teacher will read out a few and then introduce the topic- Hormones
The teacher will then introduce the term Hormones and Endocrine glands.
Teacher: In this unit we will learn how the endocrine system can help with a quick
response to danger and how it slowly turns you from a child to a pre-adolescent to an
adult.
Student Activity : 1
The teacher will pose following questions:
Who feels tired and sleepy in the first part of the school day?
Who feels sleepy in the afternoons?
Take a poll and put results on board.
Teacher: The rhythm of wakefulness is controlled by hormones.
The endocrine system works like and automatic thermostat. When the building gets
hot, the air conditioner comes on: when it is cold , the heater comes on. When our
bodies need fuel, hormones are released to stimulate feelings of hunger. When we are
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threatened, a hormone prepares our muscles to be ready for action. We are going to
find out what hormones are produced and secreted by the various endocrine glands
as well as the location of the various glands.
Although we rarely think about them, the glands of the endocrine system and the
hormones they release influence almost every cell, organ, and function of our bodies.
The endocrine system is instrumental in regulating mood, growth and development,
tissue function, and metabolism, as well as sexual function and reproductive
processes.
Endocrine System: This system helps to regulate all the body's functions. It controls
the rate we grow, our feelings of hunger, our body temperature, how much fluid we
have in our bodies and much more. The endocrine system could be called the rhythm
section of our lives. These glands secrete hormones that are responsible for how fast
and large we grow, how awake we are, how happy we feel and more. Some hormones
help us mature into adult men and women.
Student Activity : 2
The students will be shown a picture of location of endocrine glands in the body.
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WORKSHEET : 8A
Questions: Write True or False against each of the following statements:
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ACTIVITY 8B : EXOCRINE AND ENDOCRINE GLANDS
Learning outcome:
The students would be able to differentiate between exocrine and endocrine glands.
The teacher may explain:
Gland is a group of cells that produces and secretes, or gives off, chemicals. A gland
selects and removes materials from the blood, processes them, and secretes the finished
chemical product for use somewhere in the body.
Some types of glands release their secretions in specific areas. For instance, exocrine
glands, such as the sweat and salivary glands, release secretions in the skin or inside the
mouth. Endocrine glands, on the other hand, release more than 20 major hormones
directly into the bloodstream where they can be transported to cells in other parts of the
body.
The major glands that make up the human endocrine system include the:
hypothalamus
pituitary gland
thyroid
parathyroids
adrenal glands
pineal body
reproductive glands (which include the ovaries and testes)
Observe the types of glands shown in the picture. Compare their secretions and their
effect.
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WORKSHEET : 8B
1. Identify the endocrine and exocrine glands shown in the picture shown below. Give
their secretions and their target organs.
2. Explain the process shown below.
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ACTIVITY 8C : FEEDBACK MECHANISM OF HORMONE ACTION
Learning Outcome :
Students would be able to understand the feedback mechanism of hormonal action
negative feedback The stopping of the synthesis of an enzyme by the
2
accumulation of the products of the enzyme-mediated reaction.
negative feedback control Occurs when information produced by the feedback
2
reverses the direction of the response; regulates the secretion of most hormones.
negative feedback loop is A biochemical pathway where the products of the
2
reaction inhibit production of the enzyme that controlled their formation.
An example of a simple negative feedback loop
Student Activity 1:
Students will prepare a skit to
show the regulation of Glucose in
the body
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WORKSHEET : 8C
1.
Explain the negative feedback control shown in the schematic diagram shown
below:
2.
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ACTIVITY 9: REGULATION OF PHOTOPERIODISM
Learning Outcome:
The students would be able to explain the involvement in regulation of
Photoperiodism.
Content: Students track photoperiod (daylight hours) over time and predict how
daylight will change during different seasons. This helps build their
understanding that ever-changing daylight is the driving force for migrations
and all other seasonal changes.
ideas on a chart that they can revisit and revise at the end of this learning experience.
Exploration
Challenge the class to discover how the amount of daylight changes throughout the
school year.
1.
Ask students to hypothesize whether the amount of daylight (called
photoperiod) will increase or decrease between fall and winter, winter and
spring, and spring and summer. Have them explain the thinking behind their
responses.
2.
Set up a class chart, or have students use individual charts, to write down the
sunrise and sunset times for your location each day, each week, or only on the
equinoxes and winter solstice.
3.
Once students have gathered the data, they should calculate the photoperiod
(hours of daylight) - and high or average temperatures, if they have them - for
each date; Finally, they can graph their data.
PHOTOPERIODISM: The day length during which light is available to the plants is
called Photoperiod.
The effect of day length (photoperiod) on the developmental processes of plant (like
germination of seeds & flowering) is called PHOTOPERIODISM
Plants respond to photoperiodic stimulus which the help of a pigment called
Phytochrome. It is a blue green pigment which responds to light.
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e.g.
1.
Photoperiodism is involved in germination of seeds.
2.
Flowering of tobacco plants is a photoperiodic response
Phytochrome functions as a photoreceptor in many plant responses to light and
photoperiod
A pigment named phytochrome helps plants measure the length of darkness in a
photoperiod.
Phytochrome Receptors
Photoperiodism takes place in specialized pigment materials called phytochrome
2
receptors. Phytochrome receptors act as light sensors that integrate with a plant's
biological clock and provide a means for a plant to adapt to its lighting
conditions. These receptors also absorb available light energy and use it to
activate the genes involved in seed development and flowering. In effect,
phytochrome pigments can measure the time periods that elapse through
successive days and nights.
Student Activity:
Skit: Prepare a skit to show how phytochromes affect photoperiodism.
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WORKSHEET : 9
1.
2.
3.
4.
5.
Which substance(s) produced in one part of a plant affect(s) another part?
A.
oxygen and nitrogen
B.
hormones
C.
herbicides
D.
enzymes
Which hormones influence the shedding of leaves?
A.
gibberellin and auxin
B.
phytochrome and gibberellin
C.
auxin and ethylene
D.
cytokinin and phytochrome
Roots growing with gravity and stems growing against gravity are examples of
A.
photoperiodism.
B.
thigmotropism.
C.
gravitropism.
D.
phototropism.
Plant hormones are produced in
A.
the buds of flowers.
B.
roots.
C.
old leaves.
D.
flowers in full bloom.
What is a pigment that regulates the changes in activity that prepare plants for
winter?
A.
phytochrome
B.
ethylene
C.
meristem
D.
cytokinin
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6.
7.
8.
9.
Hormones that stimulate cell elongation and are produced in the rapidly
growing region near the tip of the plant's root or stem are called
A.
auxins.
B.
ethylenes.
C.
gibberellins.
D.
cytokinins.
The growth of plant seedlings is usually
A.
thigmotropic and gravitropic.
B.
phototropic and gravitropic.
C.
phototropic and influenced by ethylene.
D.
gravitropic and influenced by ethylene
The response of a plant to changes in the length of day or night is called
A.
abscission.
B.
photosynthesis.
C.
photoperiodism.
D.
thigmotropism.
The responses of plants to external stimuli are called
A.
gibberellins.
B.
tropisms.
C.
cytokinins.
D.
auxins
10. Powerful synthetic auxins are sometimes used as
A.
fertilizers.
B.
insecticides.
C.
herbicides.
D.
fruit ripeners.
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ACTIVITY 10 : HUMAN BRAIN
Learning objectives: Students will be able to
2
Describe the major regions of human brain and list their functions
Content:
The average human brain weighs about 1,400 grams (3 lb). When the brain is
removed from the skull, it looks a bit like a large pinkish-gray walnut. The brain can
be divided down the middle lengthwise into two halves called the cerebral
hemispheres. Each hemisphere of the cerebral cortex is divided into four lobes by
various sulci and gyri. The sulci (or fissures) are the grooves and the gyri are the
"bumps" that can be seen on the surface of the brain. The folding of the cerebral
cortex produced by these bumps and grooves increases the amount of cerebral
cortex that can fit in the skull. (In fact, the total surface area of the cerebral cortex is
about 324 square inches - about the size of a full page of newspaper!). Although most
people have the same patterns of gyri and sulci on the cerebral cortex, no two brains
are exactly a like.
FRONTAL LOBE
2
Located in front of the central sulcus.
2
Concerned with reasoning, planning, parts of speech and movement (motor
cortex), emotions, and problem-solving.
Find out more about the frontal lobe with the story of an unlucky worker in 1848
who survived an iron rod that went through his head!! Read about Mr. Gage and the
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frontal lobe in a GREAT multimedia slide show. If you are interested in a book about
Phineas Gage, try Phineas Gage: A Gruesome but True Story About Brain Science by
John Fleischman (Boston: Houghton Mifflin Co., 2002).
PARIETAL LOBE
Located behind the central sulcus.
2
Concerned with perception of stimuli related to touch, pressure, temperature
2
and pain.
TEMPORAL LOBE
Located below the lateral fissure.
2
Concerned with perception and recognition of auditory stimuli (hearing) and
2
memory (hippocampus).
OCCIPITAL LOBE
Located at the back of the brain, behind the parietal lobe and temporal lobe.
2
http://www.eduref.org/Virtual/Lessons/Science/Anatomy/ANA0202.html
Student activity-1.
Identify and locate parts of the brain and the actions they control by acting out the
following functions: Students will write something they remember, solve a math
problem and make a decision, then point to the top of their head to the cerebrum, as
well as on the brain diagram worksheet.
Students will cough, sneeze, and feel their pulse, and point behind their ear to the
medulla, and illustration. Balance on one foot, rub their head and pat their stomach.
Follow by pointing to the lower-back portion of their head to the cerebellum, and on
the diagram. Names of parts are said aloud as they point to them. Repeat.
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Student activity-2.
Create a nervous system model by getting into pairs, trace each other's body on
butcher-block paper, then glue twisted strands of yarn on their body tracing for the
spinal cord. Strands of yarn will be glued on extending from the s p i n a l c o r d outward through the body as the nerves. The brain will be glued on cotton balls.
Student activity-3.
Act out the parts of the nervous system and what each one's function is in a skit. One
student will be the brain, acting as the "control center". This student will send
messages to students acting as five senses and other body parts on note cards, and
receive information on note cards from those body parts and senses. Students acting
as the spinal cord will pass along the messages, and the rest of the students will run
messages and incoming information along the nerves.
A diagram will be taped on the floor of the nervous systems and t h e i r l o c a t i o n s .
http://www.franklincollege.edu/pwp/dbrown/UnitInquiries.pdf
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WORKSHEET : 10
Here is a short review about the 4 lobes of the brain. Take a look at this figure and
then answer the questions. The numbers on the figure correspond to the number of
the question.
The lobe of the brain most important for vision ...
Occipital
2.
Parietal
Frontal
Temporal
Parietal
The largest lobe of the human brain is the...
Temporal
6.
Frontal
The lobe of the brain most important for reasoning and planning...
Frontal
5.
Temporal
The lobe of the brain most important for touch ...
Occipital
4.
Parietal
The lobe of the brain most important for hearing ...
Occipital
3.
Temporal
Occipital
Frontal
The human brain weighs about ...
1 pound
3 pounds
5 pounds
Read the definitions below, then label the brain anatomy diagram.
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Cerebellum - the part of the brain below
the back of the cerebrum. It regulates
balance, posture, movement, and muscle
coordination.
Parietal Lobe of the Cerebrum - the middle
lobe of each cerebral hemisphere between
the frontal and occipital lobes; it contains
important sensory centers (located at the
upper rear of the head).
Corpus Callosum - a large bundle of nerve
fibers that connect the left and right Pituitary Gland - a gland attached to the
cerebral hemispheres. In the lateral section, base of the brain (located between the Pons
and the Corpus Callosum) that secretes
it looks a bit like a "C" on its side.
hormones.
Frontal Lobe of the Cerebrum - the top,
front regions of each of the cerebral Pons - the part of the brainstem that joins the
hemispheres. They are used for reasoning, hemispheres of the cerebellum and
emotions, judgment, and voluntary connects the cerebrum with the cerebellum.
It is located just above the Medulla
movement.
Oblongata.
Medulla Oblongata - the lowest section of
the brainstem (at the top end of the spinal Spinal Cord - a thick bundle of nerve fibers
cord); it controls automatic functions that runs from the base of the brain to the
hip area, running through the spine
including heartbeat, breathing, etc.
(vertebrae).
Occipital Lobe of the Cerebrum - the
region at the back of each cerebral Temporal Lobe of the Cerebrum - the
hemisphere that contains the centers of region at the lower side of each cerebral
vision and reading ability (located at the hemisphere; contains centers of hearing and
memory (located at the sides of the head).
back of the head).
www.enchantedlearning.com/subjects/.../brain/Classroom.shtml - Cached - Similar
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ACTIVITY 11 : EEG AS AN IMPORTANT TOOL
Learning outcome: Students will be able to
2
Understand EEG as an important tool to detect Brain diseases(lesions)
http://www.youtube.com/watch?v=KtfiQ5mdybU
EEG Brain waves game
Activity 12 : Structure and Function of The Human Eye
Learning Outcome: Students will be able to
identify the parts of the eye and
2
explain the visual system of the brain.
2
Recognise sense organs as gateways for receiving information from the
2
environment
Content:
AQUEOUS HUMOR:
clear, watery fluid circulating in both chambers of eye, associated with the chamber
outside the lens.
CHOROID:
a thin, highly vascular membrane on which the retina rests; between the retina and
sclera.
CILIARY BODY:
part of the eye that joins the iris with the anterior portion of the choroid.
CONES:
photoreceptor cells in the retina used under conditions of bright illumination; are
color coded (red, green, and blue); mediate fine detail vision; contain
photopigments with low sensitivity to light (i.e., cannot see colors in dim
illumination).
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CONJUNCTIVA:
thin layer of mucous membrane lining the inner surface of each eyelid,moves over
the eyeball as a protective cover.
CORNEA:
convex, transparent coating of the eye (made up of collagen-rich epithelial cells)
which covers the pupil and iris, consisting of five layers allowing light to pass
through to the lens; it is dense, nonvascular, uniform in thickness, and projects like a
dome beyond the sclera; the degree of corneal curvature varies in different
individuals and in the same person at different ages; curvature is more pronounced
in youth than in advanced age.
EYELID:
movable fold of skin over the eye with lashes and glands along its margin
FOVEA (FOVEA CENTRALIS):
area at the center of the retina where cone cells are concentrated and there are no rod
cells; "blind spot.”
IRIS:
circular, opaque, contractile diaphragm controlling the diameter of the pupil;
divides the space between the lens and the cornea into an anterior and a posterior
chamber; the colored part of the eye surface containing dark pigment cells variously
arranged in different people to produce different colored irises; pigment absent in
albinos.
INTRAOCULAR PRESSURE:
pressure of the eye, regulated by resistance to the flow of aqueous humor through a
fine sieve-like trabecular meshwork (eye's drainage system); the older the person,
the more likely it is that the trabecular meshwork becomes hardened and
obstructed, preventing the normal flow of aqueous humor from passing out at the
proper rate and causing an increase in the intraocular pressure (IOP).
© 2001 UTHSCSA "Positively Aging®" a trade mark of the University of Texas
Health Science Center at San Antonio 6-2 UNIT-6
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LENS (CRYSTALLINE LENS):
a transparent, colorless, firm structure of the eye, enclosed in a capsule, located
between the iris and the vitreous humor; refracts light to focus images onto the
retina at the back of the eye; in old age the lens becomes flattened, more dense,
slightly opaque, and amber-tinted.
MACULA LUTEA:
an oval yellow spot at the center of the retina, near the optic nerve; around fovea
(blind spot); region of retina richest in photoreceptors; contains a pit, fovea centralis,
and has no blood vessels; central vision occurs when an image is focused directly on
the fovea centralis.
MUSCLES OF THE EYE:
CILIARY MUSCLE - controls the diameter of the pupil (how much light passes
through the lens); ciliary muscle adjusts the shape of the lens (and hence focal
length) by varying the tension of the muscle
OPTIC NERVES:
either of a pair of second cranial nerves; transmits visual data from retina to brain.
PUPIL:
the "hole" or circular opening in the iris through which light passes to the lens and
the retina; located slightly to the nasal side of the center of the iris; lies behind the
anterior chamber of the eye and the cornea and in front of the lens; diameter changes
with contraction and relaxation of the muscular fibers of the iris as the eye responds
to changes in light, emotional states and other kinds of stimulation.
RETINA:
a ten-layered, delicate, membrane of light-sensitive nervous tissue at the back of the
eye; contains photoreceptors (rods and cones) and the neurons which transmit
visual impulses from sensory cells through the optic nerve to the brain; is in contact
with the choroid, the inner surface with the vitreous body; is soft, semitransparent,
and contains rhodopsin, which gives it a purple tint; becomes clouded and opaque if
exposed to direct sunlight.
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RODS:
one of the photoreceptor cells in the retina; contain photopigments which are very
sensitive to low light levels; located mainly around the periphery of the retina; do
not code for color.
SCLERA:
tough, opaque membrane of the eyebulb which maintains the size and form of the
bulb and attaches to muscles that move the bulb; the whites of the eyes.
VITREOUS HUMOR:
transparent, semigelatinous fluid in the chamber filling the cavity behind the
crystalline lens of the eye.
Sources: WWW.familyconnect.org
http://teachhealthk-12.uthscsa.edu/curriculum/vision-hearing/vision01aanatomy.asp
Materials Needed: paper, pencils, colored pencils, or crayons.
Classroom Activities: Select two to three activities per classroom session.
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Student Activity 1: Allow 15 minutes for students to work in pairs. Allow 5 minutes for
classroom discussion.
Divide the classroom into pairs. Ask students to examine their partner's eyes and to draw a
large picture of one eye, putting in as many details as they can. Have them notice the color
and texture of the eye, and use crayons to lightly color the drawing. Students can compare
the similarities and differences in the color, shape, and texture of each other's eyes.
Circulate through the room during this activity and stimulate discussion.
Student Activity 2 : Allow 15-20 minutes.
Distribute Handout: The Anatomy of the Eye. Ask students to fill in the parts of the
eye. Review and discuss the definitions with the students.
Student Activity 3 : Allow 10 minutes.
Pupil dilation : Divide the classroom into pairs. Ask students to observe their
partner's pupils automatically get larger and smaller as the classroom lights are
turned off for 10 seconds, then turned back on.
Explain that the black spot in the middle of the iris-the pupil-is really a hole through
which light enters the eye. The iris is a muscle that expands and contracts to control
the amount of light that enters the eye. In bright light, the iris expands and the pupil
shrinks so that only a little of the available light enters the eye.
Student Activity 4 : Allow 15 minutes.
Classroom or Take Home Activity: Distribute Handout: Optical Illusions.
Review the handout with the class.
Student Activity 5 : Allow 15-20 minutes.
Classroom or Take Home Activity: Distribute Handout: Scramble and Word
Search. Review the handout with the class.
Student Activity 6 : Allow 20 minutes.
Distribute Handout: The Visual System. Review with the students.
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WORKSHEETS : 12
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Fill in parts of the EYE
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http://www.nei.nih.gov/education/VISIONschool/schintro/VISIONSchoolPro
gram.pdf
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CENTRAL BOARD OF SECONDARY EDUCATION
Shiksha Kendra, 2, Community Centre, Preet Vihar, Delhi-110 092 India