Muscular System Marisol Gomez Period 1 - Coggle Diagram
Muscular System Marisol Gomez Period 1
flex carpi radialis
extensor carpi radialis
flexor carpi ulnarius
extensor digitorum longus
Types of muscle
Cardiac: wall of heart To keep pumping blood that circulates the body.
Skeletal: Attached to bones to skin. Main function for movement
Smooth: Unitary muscle in wall of hollow organs. Main function for contraction
smallest contractile unit
connects to end of myofbrils
between 2 discs
has an A band and half an I band
at cross section has hexagonal arrangement
one thick filament surrounded by 6 think filaments
AP arrives at axon terminal
Voltage gated channels open , calcium enters motor neuron
Calcium entry = release of ACH
ACH diffuses on sarcolemma
ACH binds to receptor , gate opens and NA+ enters.
Acetylcholinesterase degrade ACH
Sliding Filament Theory:
Sliding filament model of contraction , the slide passes thick filaments. The actin and myosin then overlap. Energy of ATP used to create power stroke between thin and thick filaments.
Z Disc: disc pulled to M line
I band : shortens
Z disc: become closer
H: zone dissapear
A band: Mover closer
Rigor Mortis: 3-4 after death. Muscles stiffen. intracellular calcium increases because of ATP. Muscles stay connected until the muscle protein breaks down.
Duchenne Muscular Dystrophy: Most common and serious of muscle destroying. Sex linked recessive. When progresses, affects head, chest, muscle and cardiac muscle. Cause, defective gene dystrophin
Myasthenia Gravis: Drooping under eyelids.
Shortage of ach receptor
Generation of end plate potential
Depolarization: generation and propagation of an action potential
Repolarization: restoration of resting condition
Major Functions of Skeletal :
Produce movement : locomotion and manipulation
Maintain Posture and body position
Generate heat as they contract
Muscle: hundreds to thousands of muscle cell , CT tissue wrapping. Blood Vessel and nerve fibers. Covered by epimysium
Fascicle : separated from rest of muscle by CT sheath. Surrounded by perimysium
Muscle Fiber: elongated multinucleate cell. Banded appearance. Surrounded by endomysium.