The Muscular System and Methods of Movement

1
The Muscular System and Methods of Movement

• Functions
• Movement
• Protection
• Body Form
• Heat production

2
Muscle Cells

• Cardiac
• Heart Muscle
• Involuntary
• Smooth
• Intestinal Muscle
• Involuntary
• Skeletal
• Bone Muscle
• Voluntary

3
Skeletal Muscle Tissue

• Muscle tissue is bundled into fibers
• Muscle fibers separate into individual fibers or
  cells
• Cells are broken down into myofibrils
• Myofibrils are divided into sarcomeres
• Sarcomeres are made of myosin and actin
• Actin Fibers move toward each other as the oars
  of the myosin fiber contract, shortening the
  length of the sarcomere and entire muscle
• The entire sarcomere contractions
• All sarcomeres contract in unison

4
How muscles move bone

• Muscles generally work in pairs
• Flexors and Extensors
• When one contracts the other relaxes
• Muscle are anchored to bone by tendons
• As the muscle shortens it moves the bone it is
  attached to

5
Muscle Injuries

• Muscle Strain
• Inflamed muscle group or tear in muscle tissue
• Muscle Cramp
• When muscles do not relax

6
Muscle Facts

• Muscles cells are multinucleated
• You are born with the same number of muscles
  cells you will have your entire life
• At maximum effort - only using 30 of your muscle
  strength
• If all your muscle could be pooled together they
  could move a mass equal to 50,000 pounds
• Strength depends on size of cell not number of
  cells
• Muscle mass 45 of your bodies weight
• Muscle weighs more then fat

7
Methods of Movement (Bacteria)

• Some bacteria have flagella
• Flagella are not made of muscle
• They are composed of filaments that move back and
  forth based on polar attraction

8
Methods of Movement (Protozoan)

• Protozoan can move by flagella
• Cilia
• Pseudopodia

9
Fungus

• Movement is through growth
• Spores are carried by the wind

10
Plant Movement

• There is no muscle tissue
• Passing water from cell to cells allows slow
  movement
• Fast movement is done by rapid change of cell
  size
• Plants also move by growth

11
Arthropods/Crustaceans/Mollusk

• Muscle is similar in function
• Structure is different
• Very little fat
• Muscle is anchored to exoskeleton
• Muscle Contraction causes movement of limbs

12
Bird Muscle

• Dark meat has more myoglibin, a special tissue
  that provides oxygen to the cells
• White meat has less
• Dark meat is usually associated with areas of
  more strenuous activity like the legs and wings