Download Worksheet - Nervous System II Lecture Notes Page

Biol 221 Worksheet
Nervous System II
Central & Peripheral Nervous Systems
I. CNS - Brain
List the four major regions of the brain
1. _____________________________________
2. _____________________________________
3. _____________________________________
4. _____________________________________
A. Cerebrum
1. Location & Regions
The cerebrum is the ______________________(largest/smallest) part
of the brain and is positioned ______________________
(superiorly/inferiorly) to the other major regions of the brain.
The two halves of the cerebrum, called ___________________________,
are separated by the ___________________________ fissure and are
joined by a large fiber tract called the _________________________
__________________________.
Each cerebral hemisphere has three regions. Outermost is the
cerebral ________________, composed of _______________(white/gray)
matter. Deep to the cerebral cortex is _____________________
(white/gray) matter. Deep within the white matter are patches
of gray matter called __________________________.
________________ (White/Gray) matter consists of neuron cell
bodies and unmyelinated processes. ______________________
(White/Gray) matter consists of myelinated axons arranged in
fiber tracts.
1
2. Cerebral Cortex
The cerebral cortex of each hemisphere is divided into five
areas called lobes. Match the five lobes to their functions.
Lobes may have more than one answer.
_____________Frontal Lobe
_____________Parietal Lobe
_____________Occipital Lobe
_____________Temporal Lobe
_____________Insula
a.
b.
c.
d.
e.
f.
g.
h.
i.
Vision
Awareness of own body
Skin sensations
Personality
Hearing
Problem solving
Smell
Speech & language
Voluntary control of
skeletal muscles
j. Reflexive disgust to smells
& contamination
3. White Matter
White matter consists of ___________________ (nuclei/fiber tracts)
made of myelinated axons. These tracts carry impulse to, from,
and within the cerebral cortex.
4. Nuclei
Nuclei are clusters of ________________________ (axons/cell bodies)
within the brain. Nuclei are found in the cerebrum imbedded in
_______________ (white/gray) matter, but are also found in the
other three regions of the brain. Different nuclei carry out
various specific functions.
B. Diencephalon
1. Location
Enclosed by the _____________________ (cerebrum/cerebellum),
and _________________ (inferior/superior) to the brain stem. The
_______________________ (lateral/third/fourth) ventricle is found in
this region.
2
2. Epithalamus
The epithalamus is the _____________ (superior/middle/inferior)
portion of diencephalon. The ______________________
(pituitary/pineal) gland is located here.
3. Thalamus
_______________________ (Superior/Middle/Inferior) portion of the
diencephalon. It consists of two ______________________
(lobes/hemispheres) that may be joined by an intermediate
mass. The thalamus is responsible for relaying ___________________
(sensory/motor) information to the cerebral ____________________
(white matter/cortex).
4. Hypothalamus
______________________ (Superior/Middle/Inferior) portion of the
diencephalon. The hypothalamus is joined to the pituitary by
the ______________________ (infundibulum/intermediate mass).
The hypothalamus not only controls the lobes of the pituitary
gland, but also regulates basic autonomic functions such as
body temperature.
C. Brainstem
1. Location
______________________ (Superior/Middle/Inferior) to the
diencephalon and ___________________ (superior/middle/inferior)
to the spinal cord.
2. Midbrain
Superior portion of brainstem. Contains nuclei involved in
______________ & _____________ responses.
3. Pons
_________________________ (Inferior/superior) to the midbrain. The
pons joins the ________________________ and the _____________________.
3
4. Medulla oblongata
_________________________ (Inferior/superior) to the pons. It
regulates __________________________ and _______________________. The
medulla oblongata is the last portion of the ____________________
before the spinal cord
D. Cerebellum
Located _______________________ (anterior/posterior) to the
brainstem and ____________________________(inferior/superior) to the
cerebrum. It consists of outer ___________________(gray/white)
matter and inner, branching ____________________(gray/white)
matter. The cerebellum functions in ____________________________
(voluntary/involuntary) coordination of body _____________________.
II. CNS – Spinal Cord
List three sources of protection for the spinal cord:
1. ____________________________
2. ____________________________
3. ____________________________
In which specific body cavity is the spinal cord located?
_______________________________
The spinal cord extends from the ___________________ ____________________
of the brain to the level of the ______ (1st/2nd/3rd/4th/5th) _______________
(lumbar/sacral) vertebra.
Gray matter and white matter are located in very different depths in
the spinal cord, compared to the brain. In the spinal cord,
_______________ (gray/white) matter is superficially located, and
________________ (gray/white) matter is deeper.
The spinal cord is not of uniform thickness along its length. There are
two areas of increased thickness called “enlargements”. The
_________________ (cervical/brachial) enlargement has increased neural
tissue to enervate the shoulder & arms; the _______________________
4
(thoracic/lumbar/sacral) enlargement has more neural tissue to
enervate the pelvis and legs.
In the CNS, bundles of fibers (axons) are called ___________________
(nerves/tracts). In the spinal cord, sensory information is carried
_______________ (up/down) to the brain by ___________________________
(ascending/descending) tracts. Motor commands are carried _________
(up/down) toward spinal nerves by _____________________
(ascending/descending) tracts.
Areas of gray matter in the spinal cord are called horns. Cell bodies of
different types of neurons are located in different horns. The cell
bodies of motor neurons are located in _________________
(ventral/dorsal) gray horns. Interneuron cell bodies are located in
___________________ (ventral/dorsal) gray horns.
III.CNS – Protection
A. Bone
The brain is protected by the bones of the ____________________ and
the spinal cord is protected by ____________________________.
B. Meninges
Match the three meninges to their characteristics. More than one
answer is possible.
_____________Dura mater
_____________Arachnoid
_____________Pia mater
a. Most superficial
(outermost)
b. Deepest (innermost)
c. Between subdural space &
subarachnoid space
d. Covers brain & spinal cord
e. Double membrane that
forms folds
5
C. Cerebrospinal Fluid (CSF)
CSF is normally clear and is similar in composition to blood
______________. All CSF is secreted by _____________________
(choroid/spinal) plexuses located within brain ___________________
(ventricles/sinuses). The largest volume of CSF is produced in the
_______________________ (lateral/third/fourth) ventricles.
List the three functions of CSF:
1. _______________________________________
2. _______________________________________
3. _______________________________________
Number the correct sequence of spaces through which CSF flows
from 1- 6, in increasing numerical order.
_______ fourth ventricle
_______ cerebral aqueduct
_______ subarachnoid space & central canal
_______ lateral ventricles
_______ blood via dural sinuses
_______ third ventricle
D. Blood-brain Barrier
The blood brain barrier helps prevent potentially harmful
substances from leaving the blood and entering _________________
(brain/spinal cord) tissues. Neuroglia called ______________________
assist in the blood-brain barrier.
IV. PNS - Nerves
A nerve is a bundle of nerve fibers or _______________ (axons/dendrites)
in the _____________ (CNS/PNS). The connective tissue covering a nerve
is called the ________________ (endoneurium/epineurium/perineurium).
The connective tissue around each fascicle is called ____________________
(endoneurium/epineurium/perineurium). The connective tissue
around each axon within the fascicles is called ________________________
(endoneurium/epineurium/perineurium). Depending on the
direction of transmission of the neurons contained in a nerve, the
nerve may be either sensory, motor, or mixed in function.
6
A. Cranial Nerves
There are ________ (12/31) pairs of cranial nerves. Cranial nerves
are found in the ______ (PNS/CNS). Different cranial nerves have
______________ (different/the same) functions; some are sensory,
others are motor, and still others are mixed in function.
B. Spinal Nerves
There are ________ (12/31) pairs of spinal nerves. Spinal nerves
are found in the ______ (PNS/CNS). Spinal nerves are ______________
(sensory/motor/mixed) in function. The dorsal root of a spinal
nerve contains _______________ (sensory/motor) fibers, and the
ventral root contains ________________ (sensory/motor) fibers.
V. PNS – Reflexes & Reflex Arc
A Reflex arc is the _____________________ (simplest/most complex)
pathway in the nervous system. List the five components, in order in
a typical reflex arc:
1. ____________________________
2. ____________________________
3. ____________________________
4. ____________________________
5. ____________________________
The response at the end of the pathway is generated by the
_______________ (receptor/effector), and is called the reflex. If the
effector is skeletal muscle, the reflex is a ________________________
(somatic/autonomic) reflex. If the effector is cardiac muscle, smooth
muscle, or glandular tissue, the reflex is an (somatic/autonomic)
reflex.
7