Unit 4

Muscular System

Understandings

• The structures and functions within the Muscular System.

• Understanding diseases and the developmental aspects related to the Muscular System

Essential Questions

• How does the muscular system provide for movement of the body and its parts, maintain posture, generate heat, and stabilizes joints?

• What are the structures and the functions of the muscles in the body’s skeletal system?

Key Concepts / Skills

1. Structure and Function of Muscle Tissue

2. Microscopic Anatomy of Skeletal Muscle

3. Skeletal Muscle Activity

4. Muscle Movement, Types, Names

5. Gross Anatomy of Skeletal

6. Development Aspects of the Muscular System

Assessments

• Performance based Assessment (PBA) – Preparation and participation in a lab practical exam.

• Lab report, worksheet, discussion, test

Standards

LS1 Define and explain the role muscle tissue

LS1 Describe the microscopic structure of skeletal muscle, and explain the role of actin and myosin containing myofilaments?

LS1 Describe how an action potential is initiated in a muscle cell and how that leads to the events of a muscle contraction.

LS1 Name and locate the major muscles of the body and state the action of each.

LS4 Explain the developmental aspects and the disorders associated with the muscular system.

Common Misconceptions

1. Sliding filament mechanism and the action between a neuron and all the skeletal muscle cells it stimulates are difficult concepts.

2. Difficult concept for students is the action between a neuron and all the skeletal muscle cells it stimulates. Discuss a motor unit and the activity at the neuromuscular junction. Be sure that students understand the interplay between the nervous system and the muscular system, which results in muscle activity.

3. Students have usually heard about muscular conditions and appreciate learning about their underlying pathology.

4. The “all-or-none” law of muscle physiology can be likened to a light switch. It is either on or off, nothing in between. Point out that this law applies to an individual muscle cell and not the whole muscle, thus providing a muscle with the ability to

generate a graded response.

5. Disorders of the neuromuscular junction, such as the effects of botulism and snake venom.

6. The use of botulinum toxin in botox injections. Explain why this toxin can be injected but not ingested.

7. Provide students with several examples of the muscle movement of prime movers and their opposing movements by antagonists. Also discuss the role of synergists and fixators in each of the movements.

8. There is a logical basis for the naming of most muscles. The name often provides clues to location, shape, size, origin, insertion, and/or action, which will help students tremendously in the memorization process.

9. Discuss disorders of the muscular system such as muscular dystrophy, fibromyalgia, and myasthenia gravis.

Suggested Learning Activities

1. Mink dissection

2. Physical therapist speak to the class about rehabilitation to muscles after surgery, an illness, an injury, or a disease condition.

Books and Materials

1. Essentials of Human Anatomy & Physiology, Pearson

2. Anatomy & Physiology Coloring Book, Pearson

3. A Dissection guide and Atlas to the Mink, Morton Publishing Company