The neuromuscular system 1.3 Flashcards
What are the 3 types of muscle fibres
- slow oxidative
- fast oxidative glycolytic
- fast glycolytic
What is the slow oxidative muscle fibre also known as
type 1
What is the fast oxidative glycolytic muscle fibre also known as
type 2a
What is the fast glycolytic muscle fibre also known as
type 2x
What determines your type of muscle fibre
Genetics
What muscle fibre type do postural muscles tend to have
Slow twitch
Why do postural muscles tend to have slow twitch muscle fibres
they need to maintain the body position over a long period of time
What are the 2 types of fast twitch muscle fibres
- Type 2a
- Type 2x
What is the contraction speed for type 1
slow (110)
What is the contraction speed for type 2a
Fast (50)
What is the contraction speed for type 2x
Fast (50)
What is the motor neuron size for type 1
small
What is the motor neuron size for type 2a
large
What is the motor neuron size for type 2x
large
What is the motor neurone conduction capacity for type 1
slow
What is the motor neurone conduction capacity for type 2a
fast
What is the motor neurone conduction capacity for type 2x
fast
What is the force produced for type 1
low
What is the force produced for type 2a
high
What is the force produced for type 2x
high
What is the fatigability for type 1
low
What is the fatigability for type 2a
medium
What is the fatigability for type 2x
high
What is the mitochondrial density for type 1
high
What is the mitochondrial density for type 2a
medium
What is the mitochondrial density for type 2x
low
What is the myoglobin content for type 1
high
What is the myoglobin content for type 2a
medium
What is the myoglobin content for type 2x
low
what is the capillary density for type 1
high
what is the capillary density for type 2a
medium
what is the capillary density for type 2x
low
What is the aerobic capacity for type 1
very high
What is the aerobic capacity for type 2a
medium
What is the aerobic capacity for type 2x
low
What is the anaerobic capacity for type 1
low
What is the anaerobic capacity for type 2a
high
What is the anaerobic capacity for type 2x
very high
What is the myosin ATPase/ glycolytic enzyme activity for type 1
low
What is the myosin ATPase/ glycolytic enzyme activity for type 2a
high
What is the myosin ATPase/ glycolytic enzyme activity for type 2x
very high
What are muscle fibres grouped into
motor units
What does a motor unit consist of
Motor neurone and its muscle fibres
Can a motor unit have different types of muscle fibres
No they’re all the same
What do the muscle fibres work with to perform a contraction
Nervous system
What does the motor neurone transmit and where to
nerve impulse to the muscle fibres
What is the neuromuscular junction
Where the motor neurone and the muscle fibre meet
What does each motor neurone have at its end
A neuromuscular junction`
Will the muscles controlling eye movements have small or large motor units
small
What is the all or none law
When the motor neurone stimulates the muscle fibre either all of them contract or none of them contract
What is the minimum amount of stimulation required to start a contraction called
The threshold
What happens if the sequence of impulses is equal to or more than the threshold
The muscle fibres in the motor unit will contract
What happens if the sequence of impulses are less than the threshold
no muscle action will occur
Can a motor unit have a fast twitch and slow twitch muscle fibre
No it has to be the same muscle fibre type
For jogging, long-distance swimming what motor unit type will the brain recruit
Slow twitch motor unit
For a greater contraction force like sprinting or power lifting what motor unit type will the brain recruit
Fast twitch motor units
What is wave summation
Repeated activation of a motor neurone stimulating a given muscle fibre results in a greater force of contraction
What is released each time a nerve impulse reaches a muscle cell
Calcium
What needs to be present for muscles to contract
Calcium
What is a tetanic contraction
Repeated nerve impulse leaving the muscles no time to relax causing calcium to build up producing a contraction
How is the muscle contraction described in a tetanic contraction
Forceful, sustained, and smooth contraction
What is spatial cummation
Impulses are received at the same time at different places on the neurone which add up to fire the neurone
What size motor units does spatial summation activate
additional and bigger motor units within a muscle to develop more force
