the neuromuscular system Flashcards
what are the 3 different types of muscle tissue?
- skeletal
- smooth
- cardiac
what are the main functional properties of muscle tissue?
Extensibility: extends to its normal resting length and beyond
Elasticity: stretch and recoil to its original length
Contractibility: can shorten quickly
Excitability: receive and respond to electrical pulse (neurotransmitters or hormones)
what is the structure of a skeletal muscle
- whole muscle wrapped in epimysium
- fibres and fasciculi wrapped in perimysium
- single muscle fibres wrapped in endomysium
- myofibrils found in single fibres
- myofilaments (myosin & actin) found in sarcomeres
what is an intermediate fibre?
a type of fast twitch fibre that can adapt in different ways depending on type of training. can respond like a slow twitch fibre.
name and describe the 3 different muscular contraction types
- Isotonic: muscle changes length as it contracts
- Isometric: contracts but does not change length
- Isokinetic: contractions that produce movement at a constant speed
what are the two types of isotonic contractions? describe them
Concentric: contactions that shorten the muscle
Eccentric: muscle lengthens as it contracts
what are the roles of a synergist and fixator muscle? give example.
synergist: contracts to assist the movement prime mover (agonist). e.g during hip extension the hamstrings are synergists for the glutes.
Fixators: muscles that contract to stabilise a fixed part of the body e.g shoulder girdle stabilise the scapula to allow better movement
what is the start and end point of a muscle called?
Origin (start) and insertion(end)
name the two nervous systems’ primary divisions
central nervous system (CNS)and peripheral nervous system (PNS)
How many pairs of cranial nerves and spinal are in the peripheral nervous system?
12 pairs of cranial and 31 pairs of spinal
spinal nerves are divided into two neurons, what are they?
sensory: carry messages to the CNS from sensory organs
motor: send impulses from CNS to muscle and glands
what are sensory receptors in the muscles called?
Proprioceptors
what does the structure of a neuron consist of? (5)
Cell body : directs activities of nueron
nucleus: stores the cells DNA
dendrites: picks up impulses
Axon: sends messages away from cell body
Myelin sheath: insulates the axon
what are the 3 muscle sense organs that form part of the autonomic nervous system and where are they found?
Joint receptors: found in ligaments and joint capsule
Muscle spindles: found in muscle belly
Golgi tendon organs (GTOs): found in tendons
to produce concentric muscle contractions a muscle must…
work against the force of gravity
