#8.1 Muscle & Movement

muscle fibers

Each muscle is composed of many fibers

muscle fibers

fiber - info from 1 axon

axon - into to 1+ fibers

accurate

the less fibers the axon has to send to = the more __________ the action

eyes: axons send info to 1 fiber

legs: axons send info to 20 fibers

neuromuscular junction

synapse between motor neuron axon and muscle fiber

muscle contraction

the only movement muscles can do

acetylcholine

neurotransmitter that excites the muscle to contract

acetylcholine

its deficit in the muscles could cause MUSCLE RELAXATION

antagonistic muscles

Opposing sets of muscles that move the muscles to opposite directions

extensor & flexor

contraction < (2) antagonistic movements

smooth

MUSCLE TYPES (LOCATION):

controls and found in internal organs

smooth

MUSCLE TYPES (LOCATION):

long thin cells

skeletal/straited

MUSCLE TYPES (LOCATION):

controls movement of body in relation to the environment

skeletal/straited

MUSCLE TYPES (LOCATION):

long cylindrical with stripes

cardiac muscles

MUSCLE TYPES (LOCATION):

found in heart

cardiac muscles

MUSCLE TYPES (LOCATION):

fibers that fuse together at points

fast-twitch

MUSCLE TYPES (SPEED):

fast contractions + easily fatigued = oxygen debt

fast-twitch

MUSCLE TYPES (SPEED):

anaerobic

fast-twitch

MUSCLE TYPES (SPEED):

used for speed and power

slow-twitch

MUSCLE TYPES (SPEED):

slow contraction + fatigue resistant

slow-twitch

MUSCLE TYPES (SPEED):

aerobic

slow-twitch

MUSCLE TYPES (SPEED):

used for endurance