Transcript The Brain - Psychology 12

Psychology 12
What makes us into the people we are today?
What separates us from animals?
What is the “mind”?
Is it simply the grey organ nestled inside every
human head—or something more?
Is it flesh or spirit?
Does the mind control the body or vice versa?
 To
understand the mind and thus people,
first, we must look at our biological
make-up to determine how we perceive
the world and interact with it…


It’s almost like running is this great friend we both
share…Anyways, that’s what I’d like to talk to you
about…running as a friend, a companion…in other
words, the relationship of running. “WHAT!?” many
of you will be saying, “I thought that I was going to
learn about how to improve my 10k time.” Go read
“Runner’s World” for that. You see, I don’t view
running as what I DO or what I AM, but as this
thing, this force, that changes me over time…
---from “Running and Me: A Love Story” by Joan
Nesbit, 1999
 Why
 One
does the writer love running so much?
of the reasons may be that people who
do a lot of running—especially longdistance running, often talk of an effect
called a “runner’s high.” The longer they
run, the more tired they get, of course; but at
some point, the runners will “push through
the wall” and “get their second wind.”
 Why does this happen?
 Why
does the writer love running so much?
 Why
does this happen?
 Endorphins, which
are neurotransmitters,
produce the euphoria of a runner’s high. As
the body deals with a very physically
stressful situation—running---the runner’s
body reacts to stress.
 What
other types of physically stressful
situations may the human body
encounter?
How do you think the nervous system will react?
The nervous system
controls your emotions,
movements, thinking and
behaviour.
 Structurally, it is divided
into two parts—the
central nervous system
[CNS] ( the brain and the
spinal cord) and the
peripheral nervous
system [PNS] (the smaller
branches of nerves that
reach the other parts of
the body.

 All
parts of the
nervous system are
protected: the brain
by the skull and
several layers of
sheathing, the spinal
cord by the vertebrae,
and the peripheral
nerves by layers of
sheathing.
 The
bony protection
of the spinal cord is
vital.
 An injury to the spinal
cord could prevent
the transmittal of
messages between
the brain and the
muscles, and could
result in paralysis.
http://www.youtube.com/watch?v=
NL1S0AhYyFw&feature=relmfu
http://www.youtube.com/watch?v=s
q9qfSusNmA&feature=related
http://www.youtube.com/watch?v=s
jyI4CmBOA0&feature=related
 The
brain uses
networks of
these neurons, so
small that 30,000
of them can fit on
the head of a pin to process
information
 Your
brain has
about 100 billion of
them!
 They help you
think, learn, move
and experience
your world.
 Neurons
depend
upon support cells
called glia.
 Glia help to
insulate, nourish
and
protect neurons.
There are about 9
glia for every
neuron.


Messenger Molecules
Neurons communicate
with each other. Within
the brain there is a
constant “chatter” of
cells as they
communicate with each
other using a language
of electrical impulses
and chemical signals.





Messenger Molecules
Information “travels” when
electrical impulses within a
neuron trigger the release of
a burst of messenger
molecules (called
neurotransmitters or NTs)
from the end of the neuron.
The NTs then flow into a tiny
space called a synapse.
.



Messenger Molecules
The NTs within the synapse
then contact the next neuron,
triggering another electrical
impulse and the continuation of
communication along the next
neuron.
FYI [the synapse is less than
one millionth of an inch wide
and is filled with fluid that
transmits the chemical from one
neuron to another]



Building Information Highways
Neurons connect with each other
to form neural networks that serve
to carry information from one area
of the brain to another.
A typical neuron forms 1000 to
10,000 synapses with other neurons,
thus forming a neural network.
Electrical impulses travel
across neurons at speeds up to 400
miles per hour. We can
instantaneously tap into a
memory, “get” a joke, feel inspired
- all because of these neural
networks.

.
 Chemical-electrical
signals
travel down the neurons
through the dendrites much
as a flame travels along a
firecracker fuse. The main
difference is that the neuron
can fire (burn) over and
over again, hundreds of
times a minute.
 Transmission
between
the neurons, or nerve cells,
occur whenever the cells
are stimulated—the neuron
fires according to the allor-none principle (when it
fires, it fires at full
strength).
 REVIEW:
 The
neuron receives
messages from other
neurons on its dendrites
 Messages are transmitted
down the axon and sent out
through axon terminals
 Neurotransmitters

Chemicals released by neurons, which
determine the rate at which other
neurons fire
 Neurotransmitters
bridge the gap
(synapse) between one neuron and the
next.
 There
are many types of
neurotransmitters
 Norepinephrine
 Endorphin
 Acetylcholine
 Dopamine
 Serotonin
 Neurotransmitters
Norepinephrine: involved in learning and
memory
Endorphin: inhibits pain
Acetylcholine: movement and memory.
An undersupply is associated with
paralysis and Alzheimer’s disease
 Neurotransmitters;
Dopamine: Learning, emotional arousal
and movement. An oversupply is linked
to schizophrenia—an undersupply is
linked to Parkinson’s disease
Serotonin: cognitive functions—memory
and learning. It also regulates intestinal
movements and mood, appetite, sleep, as
well as muscle contraction.
An undersupply of serotonin and
norepinephrine may result in depression
 Your
fingers are
dendrites
 Palm is a nerve
cell
 Your arm is an
axon
 Drugs
interfere with
neurotransmitters in the brain.
 'mind-altering' drugs change our
interpretation of the world, our
behaviour, and our mood.
 For example, cannabis, affects
neurons releasing acetylcholine,
noradrenaline and dopamine
 LSD mimics serotonin action in the
brain, which seems to explain its
hallucinogenic effects.
 Every
time
someone gets
drunk, they kill
off nerve
cells—similar
to the picture
below (look at
the dendrites)
A
New Brain Every Day

Your brain is “magni-ficient!”
Magnificent, and at the same time,
efficient, your brain changes and grows
to help you function in your life. Your
networks are the “behind the scenes”
wiring that allow you to express your
unique qualities.
 You
might have passed by old railroad
tracks with wildflowers growing nearby.
 In the past: believed that brain connections
were like railroad tracks – basically
permanent, with no significant growth and
development during adulthood.
 In aging-- neurons and connections would
fade away like old defunct railroad tracks.
 This view left little hope of reversing
memory loss or building up cognitive
reserves to promote brain health in aging.
 Learned
that neurons are more like
wildflowers rather than railroad tracks.
 Found that new neurons sprout throughout
life.
 The brain naturally develops by balancing
periods of exceptional growth - called
“blooming” - with periods of trimming
back or “pruning.”
 But things we do in everyday life – exercise,
learning something new – also promote
sprouting of new neurons.
 How
nerve cells work:
 http://www.youtube.com/watch?v=c5cab4
hgmoE&feature=related
 http://www.youtube.com/watch?v=CMnDi
epv5Os&feature=related
 http://www.youtube.com/watch?v=NL1S0A
hYyFw&feature=relmfu
Draw and label the parts of a neuron, and
describe the parts
Complete questions 2 & 5 on page 159.
 Remember
early psych
methods…
 Studying the bumps on
a person’s skull to
determine that person’s
intellect and character
traits… Luckily, we’ve come a long way from this
theory…
But—it did encourage scientists to examine the role of
the brain in human and behaviour.
 Dr. Broca
(resp. for Broca’s Area)
 A patient of Dr. Broca suddenly lost his
ability to speak—but otherwise normal
 For 30 years, he could only utter one
syllable “Tan”—became known as Mr.
Tan.
 Dr. Broca performed an autopsy on his
brain—what he found stunned scientists.
 An
area of the brain, as large as an egg
had completely deteriorated
 Since Tan’s behaviour was normal, this
meant his speech was controlled
specifically by the diseased area
 Broca
had new scientific evidence that
contradicted prior knowledge of the
brain: every part of the brain controls
every kind of behaviour (prev.
understanding)
In fact, Tan showed this idea to be wrong--the control of one specific behaviour,
like speech was localized in one
specific area/part of the brain.
 Mapping
Behaviour in the Brain:
 1870 France went to war with
Germany…two German doctors roamed
the battlefields for dying men…looking
for soldiers who skulls were blown open
from gunfire.
 They used an electrically charged mental
probe which applied to the surface of
exposed brain…
 Found:
Stimulation to the same brain
area always resulted in movement of the
dying man’s arms and legs.
 This
confirmed Broca’s findings & created
a new research tool for understanding
the brain
 Electrical
probes to map the location of
behaviour in the brain—discovered that
our psychological experiences are
controlled by nerve cells in 4 sections or
lobes of the brain’s cerebral cortex…
 Each lobe exists on both sides of the
brain—because the brain’s cerebrum is
divided into two identical
hemispheres.
 Dr. Penfield
(1940s)
 He devoted much
thinking to the
functioning of the mind,
and continued until his
death to contemplate
whether there was any
scientific basis for the
existence of the human
soul
 Dr. Penfield
(1940s)
 Electrical probes to damaged brains of
patients
 Stimulated movement and the senses, but
also memories and actual mental
experiences
 Some saw themselves at concert halls,
games, heard music, saw neighbours, and
heard people calling them…
 Dr. Penfield
(1940s)
 His patients weren’t physically perceiving
real games or listening to music—but they
had purely mental experiences
 His experiment stimulated mental
behaviour...
 We’ve
learned about the brain’s role in
behaviour—but what does this experiment
tell us of the mind?
 Will
we ever understand the mind/body
question…?
 Modern
psychologists study the physical
structure and our behaviours—perhaps
this will lead us to understanding the
“mind”
 Charles Whitman
--Killed wife and mother & 47 people from
top of tower
--People thought he must be crazed, but
those who knew him said he was normal…
 Charles Whitman
--Wrote a letter 24 hours before killing
spree. He complained of headaches and
weird thoughts and wanted an autopsy
done after his death.
--Found he had a tumor the size of a walnut
pressing down on an area in his brain that
is responsible for aggression.
 Charles Whitman
His mental illness could have been physical.
His apparent healthy “mind” could only
wander helplessly while his diseased body
destroyed it.
Lets look at the brain in our understanding
of behaviour…not the “mind”
 We
begin our exploration of
the brain at the lower end,
where the spinal cord joins the
base of the brain, and then
continue upward toward the
skull.
 Note that as we move from
bottom to top, “lower,” basic
processes like breathing
generally give way to
“higher,” more complex
mental processes.
 The
brain is the control center of the
body.
 Made up of dense "grey matter"
consisting of complicated networks of
interconnected neurons
 the brain can be superficially divided
into three main parts: the hindbrain, the
midbrain and the forebrain.
 Also, the
large
section labeled as the
BRAINSTEM includes
parts of all three of
these3 sections and
helps regulate reflex
activities important
to survival (ie,
heartbeat and
respiration)

Throughout the tour,
note that certain brain
structures are
specialized to
perform certain
tasks, a process known
as localization of
function, but also note
that most parts of the
brain are not so
specialized—they
perform overlapping
functions.

Have you ever wondered what allows you to
automatically breathe and your heart to keep
pumping—automatic behaviours and survival
responses like these are either controlled by or
influenced by parts of your hindbrain, which includes
the medulla, pons and cerebellum.

Medulla: Essentially is an extension of the spinal cord,
with many nerve fibers passing through it carrying
information to an from the brain. It also controls many
essential automatic brain functions like respiration
and heartbeat.

Cerebellum: (“little brain”) is evolutionarily, a very
old structure. It coordinates fine muscle movement
and balance. The cerebellum coordinates the
muscles so that movement is smooth and precise. It is
also crucial for our sense of balance and equilibrium

Pons: Located above the cerebellum and medulla, is
involved in respiration, movement, sleeping, waking,
and dreaming (among other things). It also contains
many axons that cross from one side to the other
(pons is Latin for “bridge”)

The midbrain is the small
part of the brain that helps
orient our eye and body
movements to visual and
auditory stimuli, and works
with the pons to help control
sleep and level of arousal. It
also contains a small
structure involved with the
neurotransmitter dopamine,
while deteriorates in
Parkinson’s disease.

Running through the core of
the hindbrain, midbrain, and
brainstem is the reticular
(netlike) formation (RF). This
finger-shaped network of
neurons filters incoming
sensory information and
alerts the higher brain
centers to important events.
Without your RF, you would
not be alert or perhaps even
conscious. In fact, some
general anestheics target the
RF so pain sensations never
register in the brain.


The Forebrain is the largest
and most prominent part of
the human brain. It includes
the thalamus,
hypothalamus, limbic
system, and cerebral
cortex.
The first three structures are
located near the top of the
brainstem. Wrapped around
them is the Cerebral cortex
(cerebrum is Latin for “brain,”
and cortex is Latin for
“covering”)

Thalamus: Resembling two
little footballs jointed side by
side, the thalamus serves the
major sensory relay center for
the brain.

Thalamus: major sensory
relay center for the brain.
Like an air traffic control
centre that receives
information from all aircraft
and then directs them to the
appropriate landing or takeoff
areas, the thalamus receives
input from nearly all the
sensory systems and then
directs this information to the
appropriate areas.


Thalamus: major sensory
relay center for the brain.
For example, while you are
reading this, your thalamus
sends incoming visual signals
to the visual area of your
cortex. While listening to
music, the information is
transferred to the auditory
area of the cortex.

Thalamus: Integrates input from
the senses
Thalamus: In addition to
relaying sensory information
to the cortex it also integrates
information from various
senses and maybe involved in
learning and memory.


Thalamus: Integrates input from
the senses
Thalamus: integrates
information
Injury to the thalamus can
cause deafness, blindness, or
loss of any other sense
(except smell).


Thalamus: Integrates input from
the senses
Thalamus: integrates
information
Damage may cause the cortex
to misinterpret or not receive
vital sensory info.
Interestingly, brain-imaging
research links thalamus
abnormalities to
schizophrenia (a serious
psychological disorder
involving problems with
sensory filtering and
perception).

Hypothalamus: Controls
basic drives, such as
hunger
Hypothalamus: Beneath the
thalamus lies the
hypothalamus (“hypo”
meaning “under”). Although
no larger than a kidney bean,
it has been called the master
control centre” for basic
drives such as hunger, thirst,
sex, and aggression.



Hypothalamus: Controls
basic drives, such as
hunger
Hypothalamus:
It also helps govern hormonal
processes by regulating the
endocrine system. Hanging
down from the hypothalamus,
the pituitary gland is
considered the key endocrine
gland because it releases
hormones that activate the
other endocrine glands.
The endocrine system is a
system of glands, each of which
secretes a type of hormone
into the bloodstream to
regulate the body.


Limbic System: Regulates
fear and other emotions
Limbic System: An
interconnected group of forebrain
structures, known as the limbic
system, is located roughly along
the border between the cerebral
cortex and the lower-level brain
structures (hence the term
“limbic,” which means “edge” or
“border”). Structures include
the hippocampus, amygdala,
thalamus, hypothalamus.
Responsible for emotions,
drives, and memory, and
involved in forming and
retrieving memories.

Limbic System: Regulates
fear and other emotions
Limbic System: The major
focus of interest in the limbic
system, and particularly the
amygdala, has been its
production and regulation of
emotions (e.g., aggression,
pleasure, arousal and fear)


Limbic System: Regulates
fear and other emotions
Limbic System: focus on the
amygdala (fear, pleasure, arousal)
Also known for its role in pleasure
or reward. A study done with
rats—stimulating certain areas of
the limbic system—cause a
”pleasure” response. The feeling
was so rewarding that he rats
would cross electrified grids, swim
through water (which they
normally avoid), and press a lever
thousands of times until they
collapsed from exhaustion—just to
have this area of their brains
stimulated.



Limbic System: Regulates
fear and other emotions
Limbic System: focus on the
amygdala (fear, pleasure,
arousal)
Damage to the front part of the
cortex which connects to the
amygdala and other parts of the
limbic system, can permanently
impair social and emotional
behaviour.
This is yet another example of
the inseparable
interconnectivity of the brain.



Cerebral Cortex: Governs
higher mental processes, such
as thinking
Cerebral Cortex: The centre
for “higher” processing.
The gray, wrinkled cerebral
cortex is responsible for most
complex behaviours and
higher mental processes. It
plays such a vital role in
human life that may consider
it the essence of life. Without
a functioning cortex, we
would be almost completely
unaware of ourselves and our
surroundings.






Cerebral Cortex: Convolutions
Although it is only about
¼ inch thick, it is made up of
approximately 30 billion neurons and
nine times as many supporting cells.
When spread out--cover an area the
size of a standard newspaper page.
How does your cortex, along with all
your brain structures fit inside your
skull? Imagine crumpling and rolling
a newspaper sheet into a ball—you
would retain the same surface area,
but in a much smaller space.
The cortex contains “wrinkles” called
“convolutions” allowing it to hold
billions of neurons in the restricted
space of the skull.


Cerebral Cortex: Hemispheres
If you’ve ever watch brain
surgery on TV—once the skull
has been opened, you’ll first
see a gray, wrinkled, cerebral
cortex that closely resembles
an oversized walnut. Like a
walnut, the cortex has a similar
division (fissure) down the
centre, which marks the left and
right hemispheres of the brain.
They hemispheres are
connected by a band of fibers
called the corpus callosum.



Cerebral Cortex: Hemispheres.
The two hemispheres make up
about 80% of the brain’s weight
and they are mostly filled with
axon connections between the
cortex and other brain
structures. Each hemisphere
controls the opposite side of the
body…
Are you right brained or left
brained?



Cerebral Cortex: Hemispheres & Lobes of the Brain
The two cerebral hemispheres are divided into eight distinct
areas, or lobes—four in each hemisphere. Like the lowerlevel brain structures, each lobe specializes in somewhat
different tasks—another example of localization of function.
However, some functions overlap between lobes.


1.
2.
3.
4.
Each lobe exists on both sides of the brain because the
brain’s cerebrum is divided into two identical
hemispheres (L&R)
Cerebral Cortex: Lobes
Frontal Lobe
Parietal Lobe
Occipital Lobe
Temporal Lobe

1.
2.
3.
4.
Cerebral Cortex: Lobes
Frontal Lobe: Receives and coordinates messages from other
lobes; motor control, speech production, and higher functions.
Includes the motor cortex which controls voluntary movements
and Broca’s area which controls speech production
Parietal Lobe: Receives information about pressure, pain, touch,
and temperature. Includes the Somatosensory cortex which
receives sensory messages.
Occipital Lobe: visual perception and vision—includes the Visual
cortex that receives and processes visual information
Temporal Lobe: Hearing, language, comprehension, memory, and
some emotional control—includes Wernicke’s area that controls
language comprehension
Cerebral Cortex: Frontal Lobes
The largest of the lobes, the two frontal lobes are located at the
top front portion of the brain hemispheres—right behind
your forehead. They receive and coordinate messages from
all other lobes, while also being responsible for at least 3
other functions: higher functions, speech production and
motor control
1. Higher functions—functions that distinguish us from other
animals, such as thinking, personality, emotion, and memory.
Damage to the frontal lobes affect motivation, drives,
creativity, self-awareness, initiative, reasoning, and
emotional behaviour. Abnormalities in FL are often
observed in patients with schizophrenia


1.

Cerebral Cortex: Frontal Lobe Functions
Higher functions—those that distinguish us from other
animals, such as thinking, personality, emotion, and
memory.
Damage to the frontal lobes affect motivation, drives,
creativity, self-awareness, initiative, reasoning, and
emotional behaviour. Abnormalities in FL are often
observed in patients with schizophrenia
Cerebral Cortex: Frontal Lobe Functions
2. Speech Production: In the left frontal lobe, on the surface
of the cortex near the bottom of the motor control area
lies Broca’s area, which is known to play a crucial role
in speech production.
.

Cerebral Cortex: Frontal Lobe Functions
3. Motor Control: At the very back of the frontal lobes lies
the motor cortex, which sends messages to the
various muscles that instigate voluntary movement.
 When you call a friend on a cell phone, the motor
control area of your frontal lobes guides your fingers to
press the desired sequence of numbers.

Cerebral Cortex: Parietal Lobes
At the top of the brain, just behind the frontal lobes, are the
two parietal lobes. They contain the Somatosensory
cortex, which interpret bodily sensations including
pressure, pain, touch, temperature, and location of body
parts.
When you step on a sharp nail, you quickly (and reflexively)
withdraw your foot because the messages travel directly
to and from your spinal cord. However, you do not
experience “pain” until the neural messages reach the
parietal lobes of the brain.

Cerebral Cortex: Temporal Lobes
The two temporal lobes (Latin for “pertaining to the
temples”)are responsible for auditory perception (hearing),
language comprehension, memory, and some emotional
control.
The auditory cortex (which processes sound) is located at the
top front of each temporal lobe. This area processes
incoming sensory information from the ears and sends it to
the parietal lobes, where it is combined with visual and
other sensory info.
In the LEFT temporal lobe, Wernicke’s area is involved in
language comprehension.

Cerebral Cortex: Temporal Lobes
The auditory cortex (which processes sound) is located at
the top front of each temporal lobe. This area
processes incoming sensory information from the
ears and sends it to the parietal lobes, where it is
combined with visual and other sensory info.
In the LEFT temporal lobe, Wernicke’s area is involved in
language comprehension.

Cerebral Cortex: Temporal Lobes
In the LEFT temporal lobe, Wernicke’s area is involved in
language comprehension.
Wernicke’s Area: German neurologist Carl Wernicke noted
patients with damage to this area could not understand
what they read or heard, but they could speak quickly and
easily. Unfortunately, their speech was often
unintelligible. It contained made-up words, sound
substitutions (girl became curl) and word substitutions
(bread became cake). This syndrome is now referred to
as Wernicke’s aphasia.

Cerebral Cortex: Occipital Lobes
(Latin “oh,” “in the back of,” and “caput,” “head”)—located
at the lower back of the brain.
Occipital lobes are responsible for vision and visual
perception.
 Damage to this area can produce blindness, even though
the eyes and their neural connection to the brain are
perfectly healthy. The occipital lobes are involved in
shape, colour, motion, and perception.

 Split-Brain
Surgery:
Cutting of the corpus
callosum to separate
the brain’s two
hemispheres. When
used medically to
treat severe epilepsy,
split-brain patients
provide data on the
functions of the two
hemispheres.
 This
information has
profoundly improved
our understanding of
how the two halves of
the brain function.
Split-Brain Surgery:
.
 One split-brain patient found that
when he dressed himself, he
sometimes pulled his pants down
with his left hand and up with his
right. However, generally most
patients show very few outward
changes in behaviour, other than
fewer epileptic seizures. The
subtle changes normally appear
only with specialized testing.

Hemispheric Specialization: although
complex activities occur in both hemispheres,
specialization of function occurs in some areas
Left Hemisphere:
1. Language Functions: speaking, reading,
writing, and understanding language
2. Emotions: Associated with positive emotions
3. Analytical: Figures things out step by step
4. Controls and senses the right side of the
body


Hemispheric Specialization: although
complex activities occur in both hemispheres,
specialization of function occurs in some areas
Right Hemisphere
1. Nonverbal Abilities: Music, art, perceptual and
spatial-manipulative skills, recognition of faces,
patterns and melodies, some language
comprehension
2. Emotions: Associated with negative emotions,
emotion expression, and emotion perception
3. Synthetic: figures things out by combining to
form wholes
4. Controls and senses the left side of the body.
 Imagine
yourself as a high school football
player (not too difficult for some!). If you
suffered a concussion while playing a
game, would you tell your coach?
There is mounting evidence linking multiple
concussions with permanent (and possibly
fatal) brain damage…
 According
to a report, “many of the 1.2 million
teenagers who play high school football
either don’t know what a concussion is or they
simply don’t care. They continue to play on
and get hurt much worse—sometimes fatally.”
 Millions
of people suffer head injuries
each year, and most of these injuries are
minor—thanks to the bony skull’s
protection for the brain. This is not the
case for traumatic brain injuries (TBI).

TBI is defined as an injury to the brain caused by
significant trauma
 Symptoms: (range from mild to severe):
headache, loss of consciousness, convulsions,
coma and death.
 Two most common brain injuries are concussions
(result from significant blow to the head) and
contusions (bruises to the brain).
 Either TBI can result in prolonged or
nonreversible brain damage and serious
problems, such as extreme changes in
personality, significant loss of motor skills,
emotional control, and mental abilities

A) Questions: Answer questions 3, 4 & 5 on
page 168.
B) Read the Case Study on page 169
Answer the following questions:
 How does split-brain surgery benefit both the
patient and humans in general? Should splitbrain surgery ever be performed on a person
with no brain disorders?
 Complete questions 1-3 from the case study.
 Let’s
work with our
right hemispheric
spatiomanipulative
skills—we are going
to build a 3-D
version of the brain.
Objective: To gain a better understanding
of the location and function of the parts of
the brain
Using your textbook, the slides and
the chart you created yesterday as
guides, create a 3-D cross section of
the left side of the brain, making
sure to include all the structures
listed in your charts (obviously,
none from the right hemisphere)
Use a numbering system on the
appropriate sections of the brain
(attached with sticky notes &
toothpicks) and write the
corresponding names of the
structures and their functions on
card stock (recipe cards)..
 Read
the Time article
on page 180-1.
 Answer
the Analyzing
the Article Questions
1-2