2 Skeletal Muscle Flashcards
Name 3 shapes of skeletal muscle
Circular Convergent Parallel Unipennate Multipennate Fusiform Bipennate
What is a muscle agonist?
Prime movers- main muscles responsible for a particular movement
What is a muscle antagonist?
Oppose prime movers
What is a muscle synergist?
Assists prime movers
What is a muscle fixator?
Stabilises action of a prime mover
What is compartment syndrome?
The anterior and posterior sections of the arm are separate. If one bleeds the pressure will increase and the nerve will be pressed causing pain.
List 4 functions of skeletal muscle
Movement
Posture
Heat generation
Stability of joints
What is isotonic contraction?
The muscle changes length and moves the load
What is isometric contraction?
The muscle does not change length when it contracts
List 4 features of Type I muscle fibres
Aerobic High myoglobin levels Red Many mitochondria Rich capillary supply Fatigue resistant
List 4 features of Type IIa muscle fibres
Aerobic High myoglobin levels Pink Many mitochondria Rich capillary supply Moderate fatigue resistance
List 4 features of Type IIb muscle fibres
Anaerobic glycolysis Low myoglobin levels White Few mitochondria Poor capillary supply Rapidly fatiguable
What are proprioceptors?
Muscle spindles tell the brain how stretched the muscle is
What is a motor unit?
A motor neurone and the muscles it innervates
Name 3 substances that can send signals to communicate between nerves and muscles
Neutrophin-3 (neurotrophins)
Cardiotrophin-1 (cytokines)
IGF 1 (insulin-like growth factors)
What is muscle tone?
The baseline tone present in muscles at rest due to motor neurone activity and muscle elasticity.
What is hypotonia?
Low level of muscle tone
What are the causes of hypotonia?
Cerebral or spinal neural shock
Myopathies- primary degeneration of the muscle
Polyneuritis- lesions of lower motor neurones
Lesions of the cerebellum
Name 4 sources of ATP
Short term ATP stores
Creatine phosphate
Glycolysis
Oxidative phosphorylation
What is intermittent claudication?
Intermittent muscle pain caused by a partial blockage
What is contracture?
A state of continuous contraction. Occurs when ATP is depleted.
Eg. Rigor mortis
