1. The Muscular System
HLTAP301A

2. The Muscular System
This topic examines different muscle types and how skeletal muscles contract and thus enable body movement

3. Types and Functions Skeletal Attached to bone Voluntary
Appears striated
Produce movement
Maintain body posture stabilise joints
Produce heat - homeostasis

4. Types and Function Smooth
Found in walls of organs like the stomach and bladder
Found in tubes and passageways such as the bronchioles and blood vessels
Involuntary
Non-striated

5. Types and Function Cardiac Found only in the heart Striated
Cells fit tightly together to allow for rapid transmission of electrical impulses
involuntary

6. Muscle contraction Two parts to this process
Excitation – the ability to receive and respond to stimulus
Contraction – the ability to shorten when stimulated

7. Muscle Tone Normal, continuous state of partial muscle contraction
Helps maintain blood pressure in blood vessels
Ready for action
Flaccid is the term for muscle without proper muscle tone

8. Naming Skeletal Muscles
Based on size, shape, orientation of fibres, location, muscle action
Size – maximus,longus, minimus and brevis
Shape – deltoid, trapezius
Direction of fibres – rectus, oblique, transverse
Location – gluteus, sub, lateralis
Number of origins – biceps, triceps, quadriceps

9. Disorders Atrophy – wasting of muscle tissue
Cramp – painful, involuntary skeletal muscle contraction
Hypertonia – increased muscle tone causing rigidity
Myalgia – pain or tenderness in muscles
Myopathy – disease of the muscles not associated with nervous system