Muscles Bio Science Flashcards
What is the cell shape and appearance of skeletal muscle
Single, very long, cylindrical, multinucleate cells with obvious striations.
What is the cell shape and appearance of Cardiac muscle?
Branching chains of cells; uni or binucleate; striations
What is the cell shape and appearance of Smooth Muscle?
Single, fusiform, uninucleate; no striations
Where is skeletal muscle found?
Attached to bones or (some facial muscles) to skin
Where is Cardiac muscle found?
walls of the heart
Where is Smooth muscle found?
the muscle in the walls of hollow visceral organs
In regards to muscles properties of muscle tissues, what does the term excitability mean?
Ability to receive and respond to stimuli
In regards to muscles properties of muscle tissues, what does the term Contractility mean?
ability to contract when stimulated
In regards to muscles properties of muscle tissues, what does the term extensibility mean?
Ability to be stretched or extended
In regards to muscles properties of muscle tissues, what does the term elastcity mean?
ability to recoil to resting length
What is a fasicle?
bundles of muscle fibres (cells)
What does the epimysium surround?
surrounds the entire muscle
what does the perimysium surround?
surrounds the bundles of fibres (fasicle)
What does the endomysium surround?
surrounds the individual muscle fibres
What are the sheaths from external to internal?
- epimysium
- perimysium
- endomysium
Define origin?
The end of the muscle tht is attached to a structure (usually bone) that remains stationary
Define insertion?
Oppposite end of muscle to the origin; that is moved by the contraction
Tendons attach……. to ………..
muscle to bone
ligaments attach …….. to ………
bone to bone
What is the Agonist ?
prime mover contracts to cause an action
what is the antagonist?
stretches and yeilds to the action of the agonist
What does the synergist do ?
contract to stabilise intermediate joints
What does the fixator do ?
stabilise the origin of the agonist
What is a muscle fibre (cell)?
long cylindrical cell with multiple nuclei just beneath the sarcolemma (cell membrane)
What is a myofibril?
densely packed rod-like organelles
- contain bundles of contractile proteins
- straitions are due to repeating pattern of dark and light bands
What is a sarcomere?
- the smallest contractile unit of muscle fibre
- sarcomere line up end to end in series, contraction of the series sarcomere leads to contraction of myofibrils and therefore muscle cells
What is the sarcolemma?
The muscle cell membrane
