Exercise 9.2 - Actin & Myosin-Microscopic Observation of Muscle
Figure 9.2 TEM of striated muscle
- Glycerinated rabbit muscle fibers
- 5 mM ATP in 0.01 M Tris-HCl buffer, pH 7.6 plus 0.05 M KCl
- 0.001 M CaCl
- Prepared slides of striated muscles (longitudinal sections)
- Phase contrast microscope, slides, coverslips
- Obtain a prepared slide of striated muscle cells. Draw the
structure of an individual cell, paying particular attention to
the striations. Measure the distance between successive bands of
the muscle and indicate these on the drawing.
- Compare the image seen in the light microscopic to that in
- Tease a small fiber from the glycerinated rabbit muscle and
place in on a microscope slide. Place a coverslip gently over the
muscle fiber and examine with a phase contrast microscope.
- Measure the distance between the bands and compare to the
distance found in the prepared slide.
- Gently lift off the coverslip (or use a second fiber) and add
a drop of ATP and a drop of CaCl. Return the coverslip and
immediately monitor the cells through the microscope. Once again
measure the distance between the bands.
To observe the contraction of the muscle, carefully add the
ATP and Ca to the edge of the
coverslip and allow it to diffuse under the coverslip. You may
also time the contraction process with a stopwatch. Finally,
variations in the ion concentration as well as alternative ions
can be added to other muscle fibers to test the effects of ions
on muscle contraction.
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Cell Biology Laboratory Manual
Dr. William H. Heidcamp, Biology Department, Gustavus Adolphus College,
St. Peter, MN 56082 -- firstname.lastname@example.org