Chapter 14 Lesson 2 The Muscular System FUNCTIONS

Chapter 14 Lesson 2 – The Muscular System

FUNCTIONS All movements Pump blood throughout body Move food through digestive system Control movement of air in and out of your lungs

Contraction = the shortening of a muscle Extension = the stretching of a muscle Example – bicep/tricep

3 TYPES OF MUSCLES SMOOTH MUSCLE Type of muscle concerned with movements of internal organs SKELETAL MUSCLE Striped, or striated, muscles attached to bones that cause body movements CARDIAC MUSCLE Special type of striated tissue that forms the walls of the heart Form the largest part of the body’s M. S. ( > 600) Intestines, bronchi of lungs, the bladder, Involuntary – work without control Voluntary - under conscious control Heart is most important muscle in body

3 TYPES OF MUSCLES SMOOTH SKELETAL CARDIAC

Care of muscular system More use = more efficient/strong Exercise strengthens the heart (more blood pumped in a 1 beat) Practice good posture Increase muscle tone Eat nutritious foods “Use it or lose it” – an unused muscle will atrophy, or waste away

Lasting PROBLEMS MUSCULAR DYSTROPHY Inherited disorder Progressive wasting away of skeletal muscles No cure, but weakening can be delayed with exercise

INJURY RELATED PROBLEMS MUSCLE STRAIN BRUISE aka “pulled muscle” = tearing or stretching of muscle fibers Discolored area under the skin caused by leakage of blood after an injury Usually occur in large muscles Treatment = ice can reduce pain/swelling Treatment = ice, wrap, rest

INJURIES CONT… TENDINITIS Inflammation of a tendon usually caused by overuse Symptoms = pain, tenderness, restricted movement Treatment = anti-inflam. meds HERNIA Protrusion of an organ or tissue through a weak area in the muscle Abdominal – protrudes through weak area in abd. wall ▪ may appear after lifting heavy objects Surgery