GENERAL CONSIDERATION OF STRIATED MUSCLE AND NEUROMUSCULAR JUNCTION Part 1 Flashcards
(28 cards)
What is the primary function of muscles ?
It is to generate force or movement in response to a physiological stimulus.
What are the for properties of the muscle ?
Excitability, contractility, extensibility and elasticity.
What is excitability ?
It is equated with responsiveness.
What is contractility ?
It is the stimulation of muscle cells to generates tension within the cell ( contraction ) which may cause the cell to shorten.
What is extensibility ?
It is when a muscle cell must be capable of extending in length in response to the contraction of opposing muscle cells .
What is elasticity ?
It is a contracted muscle cell that recoils to its resting length when the applied tension issues removed.
How are contractile cells in the body can be classified into three major groups ?
Shape, position of nuclei, presence of striation and voluntary / non-voluntary control.
What are the three major groups of muscle cells ?
1- skeletal muscle ( attach to the bones of the skeleton )
2- heart muscle
3- smooth muscle
What us the skeletal muscle responsible for ?
The voluntary movement of the bones that underlie locomotion ( movement from one place to another ), it is responsible for large and forceful movements and also small delicate movements.
What us the skeletal muscle responsible for ?
The voluntary movement of the bones that underlie locomotion ( movement from one place to another ), it is responsible for large and forceful movements and also small delicate movements,
How is the cardiac muscle is specific to the heart ?
As the biomechanics pump driving the delivery of the blood to the lungs and tissues.
What dose smooth muscle provide ?
Mechanical control of organ systems such as the digestive, urinary and reproductive tracts as well as as the blood vessels of the circulatory system and the airway passages of the respiratory system.
What is the skeletal muscle composed of ?
Numerous skeletal muscle fibers, blood vessels and nerves and connective tissue sheets that surround the muscle fibers abdominal connect the muscle to bone.
What is the percentage of skeletal muscle in body mass ?
40% to 50%
What is epimysium ?
It is an external connective tissue that surrounds the entire muscle.
What is the perimysium ?
It is the connective tissue that surround the fascicles which makes the skeletal muscle.
What is the endomysium ?
It is the third connective tissue layer in the fascicle, it separates and electrically isolated each muscle cells from each other.
What is myofibril is composed of ?
Individual contractile proteins called mayoflaments.
What are the two types of myoflaments
What are the two types of myoflaments ?
1- thin filament ( actin )
What are the two types of myoflaments ?
1- thin filament ( actin )
2- thick filament ( myosin ) .
How are myosin shaped ?
Shaped like golf clubs.
How many myosin molecules are in a single filament ?
About 300
What are the functions of myosin heads ?
1- can bind to active sites on the actin molecules to form cross-bridges.
2- attached to the rod portion by a hinge region that can bend and straighten during contraction.
3- have ATPase activity.
