The Situation

It is the twenty first century and time travel has been discovered. As part of your study of muscles, you decide to visit the several scientists of the past who contributed to current knowledge about skeletal muscle. You have a source of information that was unavailable to these scientists, the Web. Your task is to assist them in their quest. Locate websites on skeletal muscles and muscle cells. During your reading, note the answers to the following.

The Tasks

Task 1

Your first stop is the studio of Leonardo da Vinci (1452-1519) who contributed many drawings of muscle and bones based on his dissections. He asks you what the answers to the following questions would be in the twenty first century.

1. What is the approximate number of skeletal muscles in the human body?
2. How are skeletal muscles named? Illustrate this with examples of muscle names.
3. What is the structure of skeletal muscle?

Task 2

You jump ahead to the laboratory of Andrew. F. Huxley (1917-) or Hugh E. Huxley (1924-) in the 1950’s. These two scientists are not related. They independently formulated the sliding filament model of muscle movement about the same time.

1. What is the structure of a sarcomere, the unit in muscle cells responsible for generating movement?
2. Locate an animation of sarcomere movement during contraction. How would you describe the sliding filament model of muscle movement?
3. What is the power source for this movement?
4. How is this energy translated into movement of the sarcomere?
5. How does is this movement translated into movement of an arm or a leg?

Task 3

By the twenty first century, multiple medical conditions have been connected to malfunctioning muscle cells. Identify a disease or syndrome associated with muscle.

1. What are the symptoms of this disease?
2. Is the cause known? If so, describe the muscle defect?
3. What is the prognosis of the disease? Is it curable with the medicine of today?

The Process

Begin by visiting the History of Biomechanics and Kinesiology page. Note the major contributors to our knowledge of how muscle works and the length of time that muscle has been studies. The answers to the tasks may be found by visiting the links provided under Resources.

Resources

• History of Biomechanics and Kinesiology
• The Muscular System
• Structure of Skeletal Muscle
• Skeletal Muscle Systems
• Muscle Physiology
• The Sarcomere
• Muscle Control
• Hypermuscle
• Sliding Filament Mechanism of Muscle Contraction
• The Mechanism of Filament Sliding
• Joints as Simple Machines
• The Stanford Health Library
• Neuromuscular
• New York Online Access to Health

Conclusion

Scientific knowledge is a result of contributions of many investigators over time. Today, we have detailed information about the structure and function of muscle thanks not only to scientists whose work led to major advances in understanding how muscle works, but to the many scientists who filled in the details that you will find on these web pages.