Module  6.2 - Muscular Microscopic Anatomy and Physiology  

One of the bodies most ingenious systems lies in the microscopic workings of skeletal muscles. This is also one of the most complex processes we will cover during this unit. The best way to truly understand the process of muscle contraction is to 1) Review the vocab and become familiar with all of the microscopic components 2) Think about the process as a step by step checklist and 3) Review the process multiple times. 

Module 6.2 Warm-Up 

- Directions: Watch the video clip below and answer the following questions (we will watch this video later in class and review as a group - please record any questions) ANSWER IN COMPLETE SENTENCES

PLEASE READ: This video shows how an impulse from the nervous system interacts with a skeletal muscle to cause movement. We will be elaborating on this process quite a lot so please pay close attention and define any unknown terms to further your understanding. 

1) What is the neuromuscular junction? 

2) What important intracellular ion is used in this process? What's it's job?

3) What is acetylcholine? (you may have to look this one up)

4) Describe what happens with Potassium and Sodium within the muscle fiber membrane. What does this do to the membrane potential? 

Essential Vocab: 

epimysium, fascicles, insertion, origin, tendon, aponeurosis, sarcoplasm, glycosomes, myoglobin, myofibrils, stirations, A bands, I bands, H Zone, M Line, Z disc, sarcomere, myofilaments, thick filaments, thin filaments, cross bridges, actin, tropomyosin, troponin, elastic filament, dystrophin, sarcoplasmic reticulum, T tubules, triads, sliding filament model of contraction, neuromuscular junction, synaptic cleft, depolarization, repolarization



Module Objectives: 

2.1 – Describe the gross and microscopic structures of skeletal tissue structures.

2.2 – Describe how an action potential is initiated in a muscle cell

2.3 – Describe the microscopic structure and roles of myofibrils, sarcoplasmic reticulum, and T-tubules of skeletal muscle fibers

2.4  - Describe the sliding filament model of muscle contraction

2.5 – Describe the events in muscle contraction

2.6 – Describe three ways ATP is regenerated during muscle activity

2.7 – Describe and identify oxygen debt and muscle fatigue and list possible causes

2.8 – Differentiate between isometric and isotonic contractions