Celestine Miller Jeffreys Beethoven Academic Center
25 W. 47th Street
Chicago IL 60609


Through observation, demonstration and brainstorming, staff members will learn
the three different types of muscles and their functions. By building a model
of the arm, they will learn its basic anatomy and how muscles, particularly the
bicep and tricep, function in relationship to bones. Discuss the
phenomenological approach after the demonstration and field any questions or
comments from staff members.

Materials Needed:

[for groups of three]
(10) Pre-prepared wooden upperarm and forearm (humerus, radius & ulna),
attached to each other with (5) hinges; each set containing (4) nails or
screws in anatomically correct positions
(10) Oblong balloons
(5) Markers


Demonstrate movements that the three types of muscles (cardiac, smooth and
skeletal) enable us to perform. A volunteer will jump up and down (skeletal-
large muscles), frown (skeletal-small muscles), and eat (smooth). Discuss the
continuous beating of the heart (cardiac), and introduce the concept of
voluntary (skeletal) and involuntary (cardiac, smooth) control. Skeletal
muscle is striated, cardiac muscle is somewhat striated and smooth muscle has
no striations. Discuss contraction and relaxation and have each staff member
perform different types of contraction (tonic, isotonic, isometric).

Staff members will construct an arm, with bones and muscles, using wooden
sticks, balloons and nails. Distribute the "bones" (two 1 1/2" x 1 1/2" x 12"
sticks attached by a 180 degree hinge) to groups of three students. Observe
how the bones move. Attach the balloons, about 50% full of air, to nails/screws
in the bones. Observe where the muscles are attached and how they move with the
bones. Be sure to use the terms origin and insertion. Move the whole
apparatus and observe how the muscles look when they contract and relax. Using
the model, identify terms of movement (abduction, adduction, supination,
pronation, flexion and extension). Add striations with a marker and observe
how they change in appearance with contraction and relaxation.

Discuss how this approach, allowing the students to develop their own ideas and
conclusions about material, can be useful in the classroom. Also discuss
problems associated with the phenomenological approach.

Performance Assessment:

Distribute examples of performance assessment for this activity:

Excellent grasp - this student can define and identify the following terms:
skeletal, cardiac and smooth muscle; involuntary and voluntary control;
tendons, origin and insertion; abduction, adduction, flexion and extension;
striation; tonic, isotonic and isometric. Muscle and fat are not inter-
changeable. Muscles are attached to bones and move in relationship to bones.
Some muscles contract and relax synergistically, and cells of the muscles
change in appearance.
Fair grasp - this student can define and identify some of the above terms.
Muscles are attached to bones, and they relax and contract. Muscle and fat are
not the same thing. Muscles fatigue and change in size when a person exercises.

Poor grasp - this student understands that there are different types of muscles.
Muscles move with bones, and relax and contract. Muscles get tired when a
person exercises.

Portfolio - a picture of the "arm" with all anatomical parts correctly labeled
or a colored picture from the Anatomy Coloring Book.


We use muscles when we walk across a room, eat and digest an apple, or simply

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