Introduction to Muscle Tissue
1. Overview of
Muscle Tissues
- Compare and contrast the basic types of muscle tissue.
- List four important functions of muscle tissue.
2. Gross
Anatomy of Skeletal Muscle
- Explain why a skeletal muscle is considered an organ.
- Describe the importance of a skeletal muscle’s blood supply.
- Describe the hierarchical structure of a skeletal muscle, from the level of an individual muscle fiber to a whole muscle, including the three connective tissue sheaths.
- Describe and differentiate between direct and indirect attachments of muscle to bone.
3.
Microscopic Anatomy of Skeletal Muscle
- List and describe the function(s) of the following muscle fiber structures: sarcolemma, sarcoplasm, glycosomes, myoglobin, myofibrils, and myofilaments.
- Describe and be able to sketch the structure of a sarcomere.
- Describe the components and structure of a myofilament.
- Explain the organization of the sarcoplasm reticulum, terminal cisternae, and T-tubules.
4. Sliding
Filament Model of Contraction
- Explain how interactions between the thin and thick filaments result in shortening of the sarcomere.
Muscle Contraction
1. Physiology
of a Skeletal Muscle Fiber
- Describe the structure of a neuromuscular junction (motor end plate).
- Explain what a neurotransmitter is.
2.
Generating and Maintaining a Resting Membrane
Potential
- Define membrane potential and explain how the resting membrane potential is established and maintained.
- List the ions responsible for the resting membrane potential and their locations while the cell is at rest.
- Explain why a cell’s resting membrane potential is negative.
- Explain how ions move across the cell’s plasma membrane along both their concentration and electrochemical gradients.
- Describe the role of the sodium-potassium pump in the resting membrane potential.
3. Generating
an Action Potential
- Define action potential and identify types of cells that experience action potentials.
- Define ligand-gated ion channel and explain its significance in the generation of an action potential.
- Define voltage-gated ion channel and explain its significance in the propagation of an action potential.
- List the ions responsible for an action potential and the direction of their movement (into/out of the cell).
- List and describe the types of membrane transport that are used during an action potential, beginning with the release of neurotransmitter.
- Sketch a tracing (graph) of an action potential and label the different phases of the tracing.
4. Excitation-Contraction
Coupling
- Explain how muscle fibers are stimulated to contract by describing events that occur at the neuromuscular junction.
- Describe how an action potential is generated.
- Follow the events of excitation-contraction coupling that lead to cross bridge activity.
- Describe the functions of tropomyosin and troponin during excitation-contraction coupling.
- Identify the specific roles that Ca++ and ATP play in the cross-bridge cycle.
Muscle Physiology
1. Contraction
of a Skeletal Muscle
- Define motor unit and muscle twitch and describe the events occurring during the three phases of a muscle twitch.
- Explain how smooth, graded contractions of a skeletal muscle are produced.
- Differentiate between isometric and isotonic contractions.
2. Muscle
Metabolism
- Describe three ways in which ATP is regenerated during skeletal muscle contraction.
- Define oxygen deficit and muscle fatigue. List possible causes of muscle fatigue.
3. Force
of Muscle Contraction
- Describe how the degree of overlap between the thin and thick filaments affects the amount of force generated during muscle contraction.
4.
Microscopic Structure of Smooth Muscle
- Compare the gross and microscopic anatomy of smooth muscle fibers to that of skeletal muscle fibers.
5. Contraction
of Smooth Muscle
- Compare and contrast the contractile mechanisms and the means of activation of skeletal and smooth muscles in the body.
- Distinguish between single-unit and multiunit smooth muscle structurally and functionally.
