Objectives:

* Describe how an action potential is initiated in a muscle cell.
* Describe the events of muscle cell contraction.
* Define graded response, tetanus, isotonic and isometric contractions, and muscle tone as these terms apply to skeletal muscle.
* Describe three ways in which ATP is regenerated during muscle activity.
* Define oxygen debt and muscle fatigue and list possible causes of muscle fatigue.
* Describe the effects of aerobic and resistance exercise on skeletal muscles and other body organs.

 

 

 

 

Review questions: read the READING ASSIGNMENT, then answer the following questions in a word document.

Do not copy the questions, your answer MUST be in complete sentences and reflect the question.

For multiple choice questions, Put the letter of the answer only.

Head your word document:

Unit 10 Day 3 Skeletal Muscle Activity

Include your name, hour, date and class in your document.

1. After ACh attaches to its receptors at the neuromuscular junction, the next step is:

A. sodium channels open.

B. calcium binds to regulatory proteins on the thin filaments.

C. cross bridges attach.

D. ATP in hydrolyzed.

 

2. Your ability to lift that heavy couch would be increased by which type of exercise?

A. Areobuc

B. Endurance

C. Resistance

D. Swimming

 

3. Describe the events that occur from the time a motor neuron releases acetylcholine at the neuromuscular junction until muscle cell contraction occurs?

4. How do isotonic and isometric contractions differ?

5. Muscle tone keeps muscles healthy. What is muscle tone and what causes it? What happens to a muscle that loses its tone?

6. When Eric returned from jogging, he was breathing heavily and sweating profusely, and he complained that his legs ached and felt weak. His wife poired him a sports drink and urged him to take it easy until he could "catch his breath". On the basis of ehat you have learned abour muscle energy metabloism, respond to the following questions:

Why was Eric breathing heavily?

What ATP harvesting pathway have his working muscles been using that leads to such a breathing pattern?

What metabolic products might account for his sore muscles and his feeling of miscle weakness?

 

 

 

Microscopic Anatomy of Skeletal Fiber
Organizational Level of Skeletal Muscles

Click the link below to take the Self test.

Then click "Section Self-Tests".

Take Section 3 test.

Record your score under your answers to the above questions