13 terms

ap chapter 10

ap chapter 10
Structure of skeletal muscles (7)
1. Endomysium
2. Fascicle - group of fibers
3. Perimysium - membrane around perimysium
4. Epimysium - connective tissue/membrane on the outside
5. Fascia
- Sheet or thin band of fibrous tissue that covers muscles & some organs of the body
6. Tendon - attaches muscle to bone (dense connective tissue)
7. Aponeurosis (white line)
- A fibrous or membranous sheetlike tendon. (attaching muscle to muscle)
Muscle actions (6)
1. Origin - bone that doesn't move
2. Insertion - on the bone that is going to move
3. Prime mover or agonist - doing the actual function (contracting)
4. Antagonist - relax
5. Synergist - helps another muscle do its job (ex. biceps & brachilias)
6. Fixator - stabilize but loose mobility (ex. rotator cuff around hip)
muscle actions you can change
origin & insertion.
these may be changed by you moving or not moving something in your body.
muscle miscellaneous
1. muscle is an organ made up of cells, known as fiber
2. muscles must be across the joint
3. muscle is protein
-ability to hold body upright

1. Muscles exert a continual pull on bones in the opposite direction from gravity (ex. abdominal & back)
2. Nervous system responsible for muscle tone, regulation and coordination. Ultimate control of muscles is from the brain.
Functions of muscles (3) & explain
1. Movement - only is attached to bone
2. Heat production - muscle contractions produce heat (ATP). tone=constant state of contraction
3. Posture (ability to hold body upright)
Characteristics of muscle tissue (3)
1. Contractility - bring up
2. Extensibility - to put back where it was
contractility & extensibility are opposites
3. Excitability (irritability) - able to be stimulated by nerves. If no nerve actions, muscles won't move & atrophy will happen (muscles shrink & then gone)
point of attachment that doesn't move when the muscle contracts
point of attachment that moves when the muscle contracts
prime mover
directly perfoms a specific movement.
are muscles that when contracting, directly oppose prime movers. they are relaxed while the prime mover is contracting to produce movement.
muscles that contract at the same time as the prime mover. they facilitate or complement prime movers
function as joint stabilizers.