BCLN BIOLOGY 12 – Rev July 2014
Unit 13 ~ Learning Guide
Name:________________
INSTRUCTIONS
Complete the following notes and questions as you work through the related lessons.
You are required to have this package completed BEFORE you write your unit test. Do
your best and ask questions about anything that you don't understand BEFORE you
write the unit test.
U13 NOTES: DIVISIONS OF THE NERVOUS SYSTEM AND
THE BRAIN (web notes)
1. Central Nervous System
a. Spinal Cord
 Central
canal
filled
with
__________________________
__________________________.
 Gray matter made up of
________________.
 White matter made of long fibers
___________________________.
They are white because they are
covered by _________________
_________________.

The dorsal (back) part of the cord
is
specialized
to
carry
_________________ information
to the brain.

The ventral (front) part of the cord
sends messages from the
__________________________
_____________.

__________________________
run together in parallel bundles
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BCLN BIOLOGY 12 – Rev July 2014
called tracts. Left and right tracts crossover prior to entering the brain.
Therefore, left side of the brain controls _______________ of the body
and vice versa.
b. Brain
Medulla Oblongata:
 Brain Stem (bottom of the
brain).
 Pathway between ________
______________________.
 Controls vomiting, coughing,
sneezing,
hiccoughing,
swallowing.
 Controls: _______________
_______________________
______________________________________.
Cerebellum:
 Butterfly shaped.
 Rear, lower portion of the
brain.
 ____________________
___________ portion of
the brain.
 Controls Muscle coordination
(smooth,
graceful
motions)
_____________________________________________________
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BCLN BIOLOGY 12 – Rev July 2014
Hypothalamus:
 Located just above the
pituitary gland.
 Controls the __________
_____________, hunger,
thirst, sleep, body temp,
water balance, and BP.
 Maintains
homeostasis
by controlling endocrine
control, Motor control.
Thalamus:
 Above the hypothalamus
 Controls ________________________ for information going to the
_________________. Channels info to appropriate place and
prevents sensory overload.
Cerebrum:
 __________________ of the brain.
 Controls _______________________________, Perceives sensory
information, Initiates movements.
 Contains 2 hemispheres (Right and Left).
 Memory.
 Parts:
i.
Frontal Lobe - ____________________________________
ii.
Temporal Lobe - __________________________________
iii.
Parietal Lobe - ___________________________________
___________________________
iv.
Occipital Lobe - Vision.
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BCLN BIOLOGY 12 – Rev July 2014
Corpus Callosum
 Holds the hemispheres of the Cerebrum together.
 Conducts impulses from one side of the brain to the other.
At the center of it all is the Central Nervous System. The CNS is comprised of the Brain
and the Spinal Cord.
2. Peripheral Nervous System
Is made up of nerves,
which are either part of
the Somatic or the
Autonomic
Nervous
System.

________________:
Contains nerves that
control skeletal muscles,
joints, and skin. They
receive and act on
external
stimuli.
Voluntary Control

________________:
Contains nerves that
control
the
smooth
muscles of the internal
organs and the glands. Automatic, usually without the need for conscious
thought.

Two Divisions:
a. __________________________________
b. __________________________________
Both:



Function automatically (involuntary).
Serve all internal organs.
Have two motor neurons with a ganglion between
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BCLN BIOLOGY 12 – Rev July 2014
Adrenal Glands and the Sympathetic and Parasympathetic Divisions
Sudden simultaneous release of
_________________________
from
all
the
sympathetic
neurons (as in times of fright)
has a critical effect.
It causes the release of the
hormone
________________
from the interior of the
_________________________
located on top of the kidneys.
The noradrenalin and adrenalin
initiate and sustain what is
known as the "_____________
________________" response.
They prepare the body to respond to danger in the following ways:
1. ________________________________________________________________
________________________________________________________________
2. ________________________________________________________________
________________________________________________________________
3. Sudden contraction of some muscles to tense the body up for action. Included in
this is the contraction of the diaphragm. A scared person will gasp, inhaling
suddenly.
4. ________________________________________________________________
________________________________________________________________
5. Increased blood flow to the skeletal muscles so they are more able to act.
6. ________________________________________________________________
**Note that acetylcholine is the hormone secreted for the parasympathetic
system which causes the opposite conditions (see above) in the body as
compared to the sympathetic system**
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BCLN BIOLOGY 12 – Rev July 2014
Neuroendocrine Control of Bodily Functions
There is an association between nerve tissue and the body's hormones (endocrine =
hormonal). This association is between the ___________________________________
__________________________________. It can be seen that there are _________
lobes of the pituitary gland: an anterior and a posterior lobe. Both of these extend down
from the hypothalamus.
As blood passes through the ___________________________, its composition and
temperature __________________ various homeostatic responses. These responses
involve the release of hormones.
The anterior pituitary releases six major hormones that range in effect from bringing
about ________________________________________________________________.
The posterior pituitary releases ________ hormones.
The mechanism of action is slightly different for the release of the anterior pituitary
hormones than it is for the posterior pituitary hormones.
In the case where the hypothalamus detects that the effect of one of the hormones from
the anterior pituitary is required, it releases a hormone-like substance called a releasing
factor that travels through the very short blood vessel that is connected with the anterior
pituitary. This causes the release of the required hormone.
In the case of the hormones released by the posterior pituitary, the hypothalamus
actually _____________ these hormones which it releases into a nerve tract that
conducts them to the ____________________________________________.
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BCLN BIOLOGY 12 – Rev July 2014
Regardless of the mechanism, all the hormones are released into the circulatory system
and they travel about the body affecting the specific target organs for which they were
designed.
**IMPORTANT**
A good understanding of these hormones, where they are
produced, what causes their release, where they are released from and the effects they
have on the body is extremely important. A good knowledge of these hormones will also
help you in the next two units.
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BCLN BIOLOGY 12 – Rev July 2014
U13 PRACTICE: DIVISIONS OF THE NERVOUS SYSTEM AND
THE BRAIN
1. Identify and briefly describe the two major divisions of the nervous system. (4
marks)
2. Identify and briefly describe the two major divisions of the peripheral nervous
system. (4 marks)
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BCLN BIOLOGY 12 – Rev July 2014
3. The autonomic system has two major divisions:
a. What are the two major divisions called and what are their nicknames? (4
marks)
b. What effect does each branch have on the body? (2 marks)
c. Give a specific example/scenario where each division may be activated.
Identify the neurotransmitter that would be released in response to that
scenario and list some of the specific effects that the neurotransmitter
would have on the body. (6 marks)
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BCLN BIOLOGY 12 – Rev July 2014
4. Explain how the adrenal glands are involved in the body’s response to stressful
situations. (3 marks)
5. Create a flow chart to illustrate the major divisions of the nervous system,
including the following terms (9 marks):
o
o
o
PNS
sympathetic
spinal cord
o
o
o
autonomic
brain
parasympathetic
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o
o
o
CNS
somatic
nervous system
BCLN BIOLOGY 12 – Rev July 2014
6. What is the general function of the brain? (3 marks)
7. Please label the following structures on the diagram below. Please place a brief
description of each structure's function beside its label. Please be neat. (14
marks):
o
o
o
medulla oblongata
cerebellum
hypothalamus
o
o
thalamus
pituitary gland
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o
o
corpus callosum
cerebrum
BCLN BIOLOGY 12 – Rev July 2014
8. Below is a diagram of the 4 major lobes of the cerebrum. Label each lobe and
place a brief description of each lobe's function beside its label. Please be neat.
(8 marks):
~ END OF BIOLOGY 12 UNIT 13 LEARNING GUIDE ~
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BCLN BIOLOGY 12 – Rev July 2014
UNIT 13 ANSWER KEY
U13 PRACTICE: DIVISIONS OF THE NERVOUS SYSTEM AND THE BRAIN
1. Identify and briefly describe the two major divisions of the nervous system. (4 marks)
= central nervous system including brain and spinal cord for receiving and integrating
information from peripheral nervous system and directing responses to internal and
external stimuli
= peripheral nervous system is essentially all the nerves excepting those of the
brain and spinal cord and it is responsible for detecting external and internal stimuli
and transmitting the information to the central nervous system where it is then
integrated to direct a response that is then transmitted via the peripheral nervous
system to effectors
2. Identify and briefly describe the two major divisions of the peripheral nervous system. (4 marks)
= sensory (afferent) neurons that detect internal and external stimuli and transmit
the information to the central nervous system
= motor (efferent) neurons that carry signals from central nervous system to
effectors to initiate a response to stimuli
3. The autonomic system has two major divisions:
a. What are the two major divisions called and what are their nicknames? (4 marks)
= sympathetic (fight-or-flight)
= parasympathetic (=rest-or-digest)
b. What effect does each branch have on the body? (2 marks)
= sympathetic prepares the body for danger or activity such as increasing
heart rate, breathing rate, dilating pupils, sending blood to skeletal muscles
and away from intestines, limiting digestion
= parasympathetic prepares the body for recovery/rest such as decreasing
heart rate, breathing rate, constricting pupils, sending blood to digestive
system and away from skeletal muscles, enhancing digestion
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BCLN BIOLOGY 12 – Rev July 2014
c. Give a specific example/scenario where each division may be activated. Identify the
neurotransmitter that would be released in response to that scenario and list some of the
specific effects that the neurotransmitter would have on the body. (6 marks)
= sympathetic might be activated in situations of stress such as during a
test or before a big game/performance or when frightened, it will cause the
nervous system to release norepinephrine (noradrenalin) which will lead to
increased heart rate, breathing rate, dilating pupils, sending blood to
skeletal muscles and away from intestines, limiting digestion
= parasympathetic might be activated after periods of stress, when relaxing
in savasna (for the yogis out there), it will cause the release of acetylcholine
which will lead to decreased heart rate, breathing rate, constricting pupils,
sending blood to digestive system and away from skeletal muscles, enhancing
digestion
4. Explain how the adrenal glands are involved in the body’s response to stressful situations.
marks)
In situations of stress sympathetic neurons release noradrenalin (aka
(3
norepinephrine) which then cause the adrenal glands to release adrenalin
(epinephrine) which initiates the flight-or-fight response including increase heart
and breathing rates, dilated pupils, dilated airways, increased blood flow to skeletal
muscles, decreased blood flow to digestive system, and decreased saliva secretion
(hence dry mouth when stressed).
5. Create a flow chart to illustrate the major divisions of the nervous system, including the following
terms (9 marks):
o
o
o
PNS
sympathetic
spinal cord
o
o
o
autonomic
brain
parasympathetic
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o
o
o
CNS
somatic
nervous system
BCLN BIOLOGY 12 – Rev July 2014
6. What is the general function of the brain? (3 marks)
= to receive and process/integrate sensory information, to direct responses to such
information, to store and retrieve memories of such information, to use such
information to determine future responses
7. Please label the following structures on the diagram below. Please place a brief description of
each structure's function beside its label. Please be neat. (14 marks):
o
o
o
medulla oblongata
cerebellum
hypothalamus
o
o
thalamus
pituitary gland
o
o
corpus callosum
cerebrum
Medulla oblongata = respiratory and cardiac control centers, involuntary responses
such as coughing, sneezing, hiccupping, vomiting
Cerebellum = balance and coordinated/graceful movement
Hypothalamus = maintain homeostasis such as temperature, hunger, thirst, sleep,
water balance, control the pituitary gland
Thalamus = relay station that passes on important signals to the cerebrum
Pituitary gland = storing and producing hormones such as human growth hormone
Corpus callosum = physical and electrical bridge linking the right and left
hemispheres of the brain
Cerebrum = largest portion of human brain that is involved in conscious thought,
perceiving sensory information and initiating movement
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BCLN BIOLOGY 12 – Rev July 2014
8. Below is a diagram of the 4 major lobes of the cerebrum. Label each lobe and place a brief
description of each lobe's function beside its label. Please be neat. (8 marks):
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