construction of a model demonstrating neural pathways and reflex arcs

double-wire connector
from the skin.
INNOVATIONS A N D I D E A S
remaining wire to the
left side of the bulb
of the S - 2 unit .
end to the left side of
the bulb of the S -1 unit.
FIG. 17.
Double-wire connector illustrated refers to the sensory neuron units
described in the instructions (Part 2, c and D). The wires are crimped
together at A. Shorter wire (30 cm) will connect to left side of S-2 unit (B)
and longer wire (35 cm) will connect to left side of S-l unit (C). There is
another sensory neuron unit that needs to be attached in the same
manner. However, the wire endings will connect to the right side of S-l
and S-2 units.
represents the sensory neuron
E. Place the 55-cm pieces of wire (sensory), the
21-cm pieces of wire (motor), the lo-cm pieces of
wire (interneuron), and the double-wire connector
(sensory) in a bag. Label the bag POLYSYNAPTIC
MODEL.
Part 4: neuralpathway diagrams. Each neural path-
way diagram consists of four 8 X 1 l-in. pages that
serve as maps for the students to follow when
constructing their own model.3 Make enough copies
of each pathway so that each lab group has a complete
set for the patellar tendon reflex and the polysynaptic
withdrawal reflex upon painful stimulus models (Figs.
18 and 19).
3 To request a master copy of the reflex pathways for
duplication purposes, write to authors at NEOUCOM, 4209
State Route 44, PO Box 95, Rootstown, OH 44272-0095 or fax
(216) 325-2524.
Part 5: student lab packets. Each student or group of
students will need a packet containing the following
items to assemble the models: four synaptic junctions
(light/lamp and switch connected together), one low-
voltage buzzer, one low-voltage motor, four AA batter-
ies with holder, one monosynaptic wire packet in
large plastic Ziploc bag, one polysynaptic wire packet
in large plastic Ziploc bag.
TIPS FOR TEACHERS
Options
We have presented two options for classroom presen-
tation of the laboratory exercise. These two options
are only suggestions, and individual teachers may have
other ideas for the presentation of this exercise.
I. Interactive demonstration (one class period). The
laboratory would consist of demonstrating the model
that has been constructed before the students start the
lab. With this option, four students can work with one
model.
VOLUME 16 : NUMBER 1 - ADVANCES IN PHYSIOLOGY EDUCATION - DECEMBER 1996
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