Muscular Sys. Flashcards
Skeletal
Vol.
Cardiac
Invol.
Smooth
Invol.
Myosin
Thick filaments
Actin
Thin filaments
Ca++ / calcium (What happens when muscles release this)
When Ca++ binds to troponin it shifts tropomyosin to expose active sites which allows myosin to bind
What are sarcomeres composed of
Z-lines,
Strands of Actin (with tropomyosin and troponin)
Myosin
Myofibril
Strand of multiple sarcomeres
Muscle fiber (cell) what is it composed of
Myofibrils,
Organelles (specific SR- sarcomeres reticulum Ca++ storage)
Sarcolemma membrane
Endomysiom (covering)
Fascicle
Muscle fiber cells covered by perimysium
Muscle
Fascicles covered by epimysium …
Covered by Fascia
Fascia
Groups muscles with similar jobs together,
Helps perform specific functions, CT, attaches muscles to skin
Tendons
Endomysiom, perimysium, and epimysium
NMJ
Neuromuscular junction:
Motor neuron, synapse, synaptic cleft, Ach, synaptic bulb, motor end plate, Ach receptors, muscle fiber
DRAW OUT
Transmitter example
Ach
Threshold
Min. Amount
Excitability
A muscle cell can be stimulated by a nerve to contract
Conductivity
The stimulation from the nerve moves quickly along the length of the muscle
Contractility
A muscle cell can shorten with force, muscles can only pull (not push)
Extensibility
A muscle cell can be stretched,
Example
Biceps brachii contracts to flex the arm, the triceps brachii needs to stretch to accommodate the motion
Muscles are stretched by the contraction of other muscles
Elasticity
If a muscle cell is stretched, it will return to it’s original shape
Sliding filament theory
Muscle contraction involves thick filaments grabbing thin filaments and pulling therm toward the center of the sarcomeres
Twitch
Contraction of a muscle cell in response to single nerve stimulus
Latent, contraction, relaxation, refractory
Tetany
Sustained contraction due to repetitive nerve signals
Isotonic contraction
Push up
Tension in the muscle remains constant as the muscle shortens
Isometric contraction
Planking,
Tension in the muscle increases, but there is no shortening of the muscle
Levers in the human body (most common)
Third class levels
02 not provided
Anaerobic, lactic acid
O2 provided
Peruvate, H20 and CO2
Anaerobic respiration results in …
Peruvic acid
Slow-twitch fibers
Aerobic respiration, do not fatigue quickly
Fast twitch fibers
Anaerobic respiration and therefore fatigue quickly
Sprain
Tear in ligament
Strain
Tear in tendons or muscle tissue
Synergists
Muscles that have the same action
Antagonist
Muscles that have opposing action
