| A | B |
|---|
| skeletal muscle | appears striated |
| cardiac muscle | contains intercalcated disks |
| smooth muscle | found in walls of digestive tract/blood vessels |
| motion is voluntary in this muscle | skeletal muscle |
| motion is involuntary in this muscle | cardiac muscle, smooth muscle |
| origin | where muscle attaches to stationary bone |
| body | main part of the muscle |
| insertion | where muscle attaches to bone that moves on contraction |
| tendons | connective tissue that attaches muscle to bone |
| tendon sheath | fluid-filled tube enclosing some tendons |
| bursae | fluid-filled sac between tendon and bone |
| fiber | muscle cell |
| sarcomere | basic unit of muscle |
| actin | protein making up thin filaments of sarcomere |
| myosin | protein making up thick filaments of sarcomere |
| sliding filament model | describes/explains muscle contraction |
| requirements for muscle contraction | ATP molecules and calcium ions |
| movement, posture, heat production | functions of muscular system |
| prime mover | muscle mainly responsible for a given movement |
| synergist | muscle that helps prime mover |
| antagonist | muscle that opposes action of prime mover |
| prime mover must do this to produce motion | contract |
| antagonist must do this to allow motion | relax |
| bicep | muscle in anterior upper arm that is prime mover in flexion of lower arm |
| tricep | muscle in posterior upper arm that is antagonist in flexion of lower arm |
| fatigue | caused by repeated muscle contraction without rest |
| lactic acid | builds up in muscles during rapid exercise |
| motor unit | combination of motor neuron and muscle fiber |
| motor neuron | specialized nerve cell that stimulates a muscle fiber |
| neuromuscular junction | point of contact between motor neuron and muscle fiber |
| threshold stimulus | minimum stimulus needed to cause muscle fiber to contract |
| isotonic contraction | muscle shortens and produces movement |
| isometric contraction | muscle tenses and produces no movement |
| pectorals "pecs" | chest muscle |
| latissimus dorsi "lats" | back muscle |
| deltoids "delts" | shoulder muscle |
| biceps | anterior upper arm muscle |
| triceps | posterior upper arm muscle |
| flexion | movement that makes joint angle smaller |
| extension | movement that makes joint angle larger |
| supination | palms forward |
