ZOOL 409 Tuesday and Thursday Lab Week 13
4.
Slide 10 -- Peripheral nerves.
 This slide of "artery, vein, nerve" includes relatively large nerves cut in cross section.
1.
Slide 88 -- Spinal cord smear. This is a smear preparation, not a section (i.e., a bit of spinal gray matter, not sliced but simply spread out and pressed down on the slide). This may be our best slide to see some of the shape of nerve cells .
 The conspicuous space between nerve sheath and nerve fibers is an artifact from tissue shrinkage.
 The sheath is fibrous connective tissue
(mostly collagen and fibroblasts).
 Note texture of cytoplasm with Nissl bodies
(basophilic granules, rough endoplasmic reticulum ).
 Nuclei that appear among the nerve fibers belong to Schwann cells .
5.
Slides 62, 32, 76 -- more nerves.
 Note dendrites tapering away from cell bodies. o
In slide boxes 1 and 8, look on each neuron for a pale axon hillock and thin pale axon. This feature will not be visible on most nerve cells (depending on how the cells was flattened onto the slide) and may not be apparent anywhere on a given slide.
 Peripheral nerves may be found on many different slides. Look in connective tissue
(often near larger blood vessels) for a bundle of fibers enclosed in a more-or-less distinct sheath.
 Note very numerous small nuclei belonging to glial cells .
6.
Slide 86 -- Nerve spread .
 Some blood vessels may also be stretched across the specimen.
 This slide displays a bit of nerve teased apart and flattened on the slide, not sliced.
2.
Slides 89, 90, 91, 92 -- Spinal cord sections , with various stains.
 Nerve cell bodies appear prominently in the ventral horn (the shorter, broader arm of the
" H " of gray matter).
 Myelin and nodes of Ranvier should be visible. Most of the thickness of each nerve fiber is myelin; nodes are the neat gaps that appear between one myelin segment and the next.
7.
Slide 87 -- Motor nerve endings .
 Slide 92 includes nerve roots and dorsal root ganglion .
 This slide is a bit of striated muscle (not a slice, but a spread) dissected at the site where a motor axons synapse with muscle fibers.
3.
Slides 91, 92-- Ganglia.
 On slide 92, look for dorsal root ganglion beside the spinal cord. This is a Golgi stain for Golgi bodies.
 Also see Auerbach's plexus , in the GI tract
(e.g., slides 42, 43, 45, 44), between the circular and longitudinal layers of smooth muscle.
 Hunt for the long black nerve fibers, then try to follow them to motor end plates.
Practical Quiz : see reverse side.
THURSDAY Objectives
Central Nervous Tissue.
See reverse side of this page.
Last updated: 12 April 2012 / dgk

ZOOL 409 Tuesday and Thursday Lab Week 13
TUESDAY Objectives: See reverse side.
A
RTEFACT
A
LERT
Nervous tissue is difficult to fix well, and often displays substantial shrinkage. This is manifested as "halos", or clear empty spaces surrounding various structures, particularly blood vessels and nerve cell bodies.
1.
Slides 89, 90, 91, 92 -- Spinal cord sections , with various stains.
 Distinguish gray matter , forming an " H " or
"butterfly" shape surrounded by white matter .
Although such halos are artefacts, they are also a fairly standard "feature" that helps call attention to blood vessels and cell bodies. The viewer must bear in mind that surrounding neuropil should be closely apposed to the haloed structures.  Note cell bodies of motor neurons in the ventral horn , the shorter, broader arm of the
" H " of gray matter:
 Distinguish white matter , forming dorsal, ventral, and lateral columns of axons travelling up and down the cord.
Practical Quiz
This quiz will simply confirm recognition of some basic features on your slide-box slides.
2.
Slides 96, 97, 98, 99, 100
Cerebral cortex .
□
On slide 88:
Indicate the nucleus of a neuron.
Indicate the nucleus of a glial cell.
 On all of these slides, find nerve cell bodies and note the associated volume of neuropil
(consisting of dendrites and axons, where most synapses are located). Note many blood vessels.
□
On slide 91 or 92:
Indicate nerve cell body in ganglion.
□
On any appropriate slide:
Indicate neuron in Auerbach's plexus..
 Slide 98 is a Golgi stain for nerve cells and astrocytes.
 Astrocytes are also demonstrated on Slide 99.
□
On slide 90 or 92:
Indicate white matter.
Indicate nerve cell body in ventral horn.
 Slides 96 and 97 are silver stained, offering some sense of neuropil structure.
 Slide 100 is stained for microglia, probably frog brain. (In blood vessels, red blood cells have nuclei.)
□
□
On slide 86:
Indicate a node of Ranvier.
On slide 62, 32, 34, 76, etc.:
Indicate a peripheral nerve.
3.
Slides 94, 95 -- Cerebellar cortex .
 On these slides, note the distinct layers, with large cell bodies of Purkinje nerve cells in the
Purkinje cell layer between the granule cell layer and the molecular layer .
□
On slide 93, 96, 97, 98, 99, 100:
Distinguish nerve cells from glia.
Indicate a blood vessel.
□
On slide 94 or 95:
Indicate a Purkinje cell.
Last updated: 13 Dec. 2011 / dgk