Unit 3A/B worksheet
1) The CNS neuroglia _____________and ______________and has less / more cells than
neurons. In the CNS _______________ are star shaped cells which attach neurons to
__________vessels and form the ____________ __________ barrier, which _________the
neuron___________.
2) In the CNS ____________________extend processes, to form __________sheath, the
nodes of __________ are further apart. Unlike_______________________, oligodendrocytes
do _______ associate with ________________ fibers.
3) The CNS ____________is the only __________system cell in the__________, which monitor
CNS__________, and if ___________are present they convert into ______________that eat
bacteria. And lastly the ependymal lines the ___________of the CNS that are filled with
______________ _________(CSF). It is a ____________barrier between the ____________
___________(CSF) and the ______________fluid of the CNS. It forms and ___________CSF
from the ___________and also encloses CSF. Cilia found on these cells ____________CSF. 3A 2
4) In the _______________Nervous System (PNS) the _____________cells also called
____________________form the ____________sheath, where as, the ____________cells
support neurons of_______________.
5) Nerve impulses are __________ ______________which are waves of _____________
charges flowing through a __________from the _____________to the cell ________to the
_____________where positively charges ____________ (Na+) ions flow ________the cell
causing the _______________changes.
6) The smaller / bigger the size of the nerve fiber, the slower / faster the speed of nerve impulse.
And the less / more myelin which means larger ____________of the nerve fiber the greater
the________________.
7) Bundles of __________and ____________neurons outside the __NS but ________the __NS
are referred to as___________. While bundle of __________and ___________neurons within
the __NS are referred to as____________.
8) In the PNS the __________cells or the __________ sheath wrap around the axon and are
referred to as the______________. Between adjacent _____________are spaces made up of
________________ nodes and these nodes are referred to as the _________of____________.
The speed of the stimulus __________as it jumps from node of __________to node of _______
9) Multipolar neurons have several _____________and _______axon extended from the cell
body which is the most common type, examples of this type are the ___________ cell of the
cerebellum and the pyramidal cell of the________________ .
10) The bipolar neuron has _______ dendrite and _______ axon with the cell body in_________,
these are rare and found only in specialized ___________organs such as the retina of the _____
and olfactory epithelium of the_________.
11) The unipolar or _________________has _______ process where a dendrite ________with
an axon, these are formed from __________neurons in the_____________. These are mainly
found in the __NS, but seldom in the __NS where they are found only in _________root ganglia
of the spinal cord and sensory __________of cranial nerves in which ___________ neurons bring
information to the CNS.
12) Interneurons or _____________neurons, are the most ____________neurons, they are
___% of the neurons found in the body and are located in the cerebral___________, the
cerebellum and the ___________cord. They carry impulses from __________neurons to
__________neurons and interneurons to___________. Examples of these would be the
_________cells of the cerebellum and the _____________cells of the cerebrum which are
____________neurons which are found in __________matter and are _______________in the
most part.
13) In an action_____________, the stimulus is sent through the ____________from the
______________to the cell body to the___________. As a stimulus transfers from cell to cell it
goes from pre-synaptic neuron which would be the _________that it originated from, to the
post-synaptic neuron which would be the ___________of the neuron it is transferring to and
again to the next _________eventually to the ________which could be a _______or a gland. The
synaptic cleft is the _________between the ________-synaptic neuron (axon) and the _______synaptic neuron (dendrite).
14) Most synapses, are ____________synapses in which the ___________________is secreted
by the _______-synaptic cell which then diffuses across the synaptic ________to the _______synaptic cell. This occurs in a ______way direction and is _________than the action potential.
15) Regeneration of nervous tissue is __________because at 6 months of age the _________
apparatus of the neurons is________. Neurons don’t do_________, as they are too__________.
After that the __NS axons may be replaced if the _________cells are okay, and they can form
regeneration neuron________. In the CNS ___________________do not promote regeneration
following damage because they die and the ______________stop the process and make scar
tissue which physically prevents_________________. Therefore, injury to the CNS is usually
_________________ while injury to the PNS may be______________.
16) Protection for the CNS is done by the________, ________and the _________________
________(CSF). The brain is further protected from harmful substances by the___________
____________ ___________.
17) Meninges are made up of _________connective tissue membranes external to the CNS which
are the _______ mater which is very________, the ___________mater which has a spider
_______look and contains ________vessels along with __ __ __ and the _______mater which is
very __________ tissue.
18) The functions of the meninges are to _________and _________the CNS, and also protect
____________vessels and _________venous ___________that _________CSF back to
the___________, as well as contain the __ __ __ and form ____________ in the brain.
19) The dura mater is very _________and is composed of ______fibrous connective tissue layers
around the brain but only _______ layer around the spinal cord. The two layers separate in certain
areas and form dural_________. The dural _______extend between ___________ referred to
as the ________ ___________which attaches to the crista galli of the __________ bone to
limit its___________________.
20) The arachnoid mater is the __________layer and it forms the loose brain ___________and
is separated from the dura mater by the _____________space. Beneath the arachnoid mater is a
wide space referred to as the ____________space which is filled with _________and large
____________vessels. Arachnoid _______ protrude superiorly and permit CSF to be _________
into the ___________ blood.
21) The _____mater is the __________layer and is the _________connective tissue that clings
tightly to the __________.
22) Cerebrospinal fluid (CSF) is a __________solution similar to blood__________, although it
contains less ____________ and has different______. Its function is to________, gives
____________, prevents delicate brain matter from being___________, protects, ________
and carries __________ signals through it.