Skeletal Muscle Tissue Flashcards
What are the functions of muscle tissue?
Produce body movements
Stabilise body positions
Regulates organ volumes- bands of smooth muscle called sphincters will control this
Movement of substances within the body
Produces heat through involuntary muscle contractions
Changes size and shape of internal organs
Properties of muscle tissue
Excitability- responds to chemicals related from nerve cells
Conductivity- ability to propagate electrical signals over membrane
Contractility- ability to shorten and generate force
Extensibility- ability to be stretched without damaging the tissue
Elasticity- ability to return to original shape after being stretched
What is skeletal muscle tissue?
Attached to bone, skin or fascia
Made up of hundreds of muscle fibres. At the peripheral of muscle fibres are satellite cells which represent a source of undifferentiated myoblast cells that may be involved in the limited regeneration capabilities of the skeletal muscle
Voluntary control of contraction and relaxation
What are the functions of skeletal muscles?
Produce skeletal movement
Maintain body positions
Guard body openings
Support soft tissues
What are the skeletal muscle structures?
Connective tissue
Nerves
Blood vessels
Skeletal muscle tissue
The outer layer epimysium
Surrounds the whole muscle
Exterior collagen layer
Connected to deep fascia
Separates muscle from surrounding tissues
The middle layer perimysium
Surrounds muscle fibre bundles (fascicles)
Contains blood vessel and nerve supply to fascicles
The inner layer endomysium
Surrounds individual muscle cells (muscle fibres)
Contains capillaries and nerve fibres contacting muscle cells
Contains satellite cells that repair muscle damage
Muscle attachments
Endomysium, perimysium and epimysium come together at the ends of muscles
To form connective tissue attachment to the bone matrix
What are nerves?
Skeletal muscles are voluntary muscles controlled by nerves of the CNS and regulated by the peripheral nerves
What are a collection of muscle cells supplied by?
A motor neuron
What is a motor unit?
One motor nerve and the muscle fibre it supplies
When the motor nueron develops an action potential, all of the muscle fibres in the motor unit it innervates develop action potentials fasting the, to contract simultaneously.
How is a muscle cell supplied?
By a terminal branch of a motor nueron. All the fibres work together during a muscle contraction
What are blood vessels?
Supply large amounts of oxygen
Carry waste products away
Supply nutrients
Each muscle cell comes into contact with 1 or 2 capillaries
What are nerve fibres and capillaries found?
In the endomysium between individual cells
