Muscle Tissue

Muscle Tissue

After studying this chapter, readers should be able to

1. Compare the contraction mechanisms of cardiac muscle and skeletal muscle.

2. Differentiate between muscle tissue excitability, contractility, extensibility, and elasticity.

3. Explain the four major functions of muscle.

4. Describe the structure of a skeletal muscle.

5. Identify the functions of transverse tubules, myofibrils, and the sarcoplasmic reticulum.

6. Describe a motor end plate and the function of a neurotransmitter.

7. Discuss the sliding filament model.

8. Explain the relationship between cellular respiration and heat production.

9. Differentiate between isotonic and isometric muscle contractions.

10. Describe two major types of smooth muscle.

Overview

Muscles are needed for many body activities, including breathing, talking, walking, and even sneezing. Important body functions performed by muscles include movement, joint stabilization, support of soft tissues, encircling digestive and urinary tract openings, posture maintenance, nutrient storage, and the generation of heat. Muscles contract by using chemical energy from nutrients. They are made up of highly specialized cells. Other actions of muscles include generating the heartbeat, distribution of heat, moving body fluids and food through the body, and providing muscle tone, which does not produce active movements. Instead, it keeps muscles healthy, firm, and ready to respond to stimulation. The three types of muscle are skeletal, smooth, and cardiac. This chapter focuses primarily on skeletal muscle. Skeletal muscle tone additionally helps to maintain posture and stabilize joints.