Unit 4: The Nervous System
Lab 1: Nervous Tissue
Jessica Radke-Snead, RD, MS
Bio 241 Anatomy & Physiology
Reminders
• Unit 3 Lab 3 Assignment: Correction for points
back
• Unit 4: This is a big unit…
– Read through the study guide and set a strategy
– Read through your labs/lectures BEFORE class
– Please see me if you need help with getting
started!
Structure of Neuron
___ receive stimuli from synapses or sensory
receptors and carry nerve impulses toward cell
body
What is the “control center” for the neuron called?
___ ___ (tigroid substance) are a form of rough ER
 manufacture and release of proteins
___ carry nerve impulses away from the cell bodies
and interact with muscle, glands or other neurons
Neuroglia of the PNS
___ cells form the neurolemma around all PNS
nerve fibers, myelin around most of them, and
aid in regeneration of damaged nerve fibers
___ cells surround neuron cell bodies in ganglia
and regulate the environment around the
neurons and are highly sensitive to injury and
inflammation
Neuroglia of the CNS
___ form the myelin sheath of the CNS
___ provide immunity to nervous cells by
phagocytizing and destroying microorganisms,
foreign matter and dead nervous tissue
___ cells line the brain ventricles and central
canal of the spinal cord, secrete and circulate
CSF
Neuroglia of the CNS
___ have the most diverse function of any glia:
– Form a supportive framework for nervous tissue
– Stimulate blood capillaries to form the BBB
– Convert blood glucose to lactate (supply nutrients)
– Secrete nerve growth factors
– Communicate electrically with neurons
– Regulate the chemical composition of the tissue fluid by
absorbing NT’s and potassium ions
– Form scar tissue and fill excess space when neurons are
damaged
Gray Matter (Low power)
Identify the following in
this slide:
Multipolar neuron
Nissl Bodies
Nucleus
Nucleolus
Nerve fibers/axons
Neuroglial nuclei
Multipolar Neuron
Identify the Nodes of Ranvier
Why are the Nodes of Ranvier significant to
neuron function?
Are these nerves myelinated or
unmyelinated?
What is this layer of
connective tissue
called?
What is this layer of
connective tissue
called?
What cells form
myelin sheath in
the PNS? CNS?
What is this?
What is this layer of
connective tissue
called?
What is this layer of
connective tissue
called?
What is this?
What type of cells
surround this
neuron?
What type of
neuron is this?
What is this?
Meninges
2
3
1
This slide is a crosssection of what
type of matter?
What are the 3
spinal meninges?
What are the
spaces between
meninges called?
Dorsal or ventral
grey horn?
Dorsal or ventral
grey horn?
What is this line?
What is this line?
Explain why both the gray and white
matter are their respective colors.
What do the
posterior and
anterior white
commissure
connect?
Which spinal
meninge is this?
Which horn is this?
Which horn is this?
What type of cells
would you find
here?
Which horn is this?
Which spinal
meninge is this?
Which spinal
meninge is this?
Introduction to Lab 2:
Neurulation
Neurulation:
Development of the Neural Tube
• ~Day 18,
embryonic
ectoderm thickens
to form a neural
plate, which
eventually gives
rise to the CNS
• ~Day 20, neural
plate forms the
neural groove with
neural folds on
each side
Neurulation Continued
• ~Day 21, neural folds fuse to form the neural tube
– Closure begins in the middle of the embryon and
progresses toward both cephalic (faster) and caudal
ends
• ~Day 26 (cephalic end) to 28 (caudal end),
neural tube closes
• The lumen of the neural tube develops into the
central canal of the spinal cord and the ventricles
of the brain
• Some ectodermal cells separate from the rest to
form a neural crest  Neural crest cells become
sensory neurons, sympathetic neurons, Schwann
cells, etc.
Primary Structures of the CNS
Week 4
Secondary Vesicles
• Prosencephalon divides into:
– Telencephalon  Cerebral hemispheres (lateral
outgrowths), cerebral cortex, basal ganglia,
hippocampus, amygdala
– Diencephalon  Retinas (optic vesicles), thalamus,
hypothalamus
• Mesencephalon  Tectum and tegmentum
• Rhombencephalon divides into:
– Metencephalon  Pons and cerebellum
– Myelencephalon  Medulla oblongata
Secondary Structures of the CNS
Week 5
Lab 1 Objectives
• On the designated neural tissue slides, be sure
that you are able to identify and discuss the
function of each component described in your
guide
• From Lab 2, work on:
– Cerebral meninges
– Organization of tissue in the brain
– Skull review
– Primary and secondary embryonic strutures