NM Physiology & Exercise Flashcards
What are the 3 main parts of the brain?
Cerebrum
Cerebellum
Brainstem
Where is the Cerebellum located?
Under the Cerebrum
Function fo the cerebellum
Coordinate muscle movement
Maintain posture + balance
Function of brainstem
Acts as a relay centre connecting the cerebrum + cerebellum to the spinal cord.
What composes the CNS
Brain
Spinal cord
What composes the PNS
Spinal nerves branching form the spinal cord
Cranial nerves branching from the brain
Which out of the 3 main parts of the brain is the largest?
Cerebrum
What is the cerebrum composed of?
Right + left hemispheres
Function of the Cerebrum
Interpreting touch, vision, hearing, speech, emotions, learning + fine control of movement.
What are the right hemisphere + left hemisphere the cerebrum in the brain joined by?
Bundle of fibres called the Corpus Callosum
What does the Corpus Callosum in the Cerebrum do?
Transmits messages from one side of the brain to the other.
What does each hemisphere of the cerebrum control?
The opposite side of the body.
What does the left hemisphere of the brain control?
Speech
Comprehension
Writing
What does the right hemisphere of the brain control?
Creativity
Spatial ability
Artistic + musical skils.
What is the surface of the cerebrum called?
Cortex
How many neurones does the cortex contain?
16 billion
What does the grey matter of the brain contain?
Most of the brains neuronal cell bodies.
What is the grey matter of the cortex involved in?
Muscle control
Sensory reception
What gives the white matter of the cortex its name?
The myelin sheath of neurones
What divides the brain into lobes?
The fissures in the cerebral hemispheres
How many lobes are in each hemisphere of the brain?
4
What are the 4 lobes in each hemisphere of the brain?
Frontal
Temporal
Parietal
Occipital
Frontal lobe responsibilities
Personality, behaviour + emotions
Judgment, planning, problem solving
Speaking + writing
Body movement
Intelligence
Parietal lobe responsibilities
Interprets language
Sense of touch, pain + temp
Interprets signals from vision, sensory + memory
Spatial + visual perception
Occipital lobe responsibilities
Interprets vision (colour, light, movement)
Temporal lobe responsibilities
Understanding language
Memory
Hearing
Which functional area of the cerebral cortex is responsible for muscles of speech
Broca’s area
Which functional area of the cerebral cortex is responsible for smelling
Olfactory area
Which functional area of the cerebral cortex is responsible for muscles of written + spoken language comprehension
Wernicke’s Area
Where does the initiation of our voluntary muscles come from in the brain?
Motor function area
What are the 2 types of cells in the brain?
Nerve cells (neurones)
Glia cells
What do ALL neurones consist of?
Cell body
Dendrites
Axon
How does a neuron convert information
Through electrical + chemical signals
Purpose of dendrites on a neurone
Specialised to receive chemical signals from the axon termini of other neurones.
They convert these intro smaller electric impulses + transmit them inward towards the cell body.
What is the soma of a neurone?
The cell body of a neurone
What does the soma/cell body of a neurone contain?
Nucleus
Cytosol
What is the axon hillock?
Specialised part of the cell body of a neuron that connects to the axon.
Where is the initiation in action potentials in the neurone?
In the axon
What is axoplasmic transport and what is it responsible for?
Cellular process
Responsible for movement of mit, lipids, synaptic vesicles, proteins + other organelles to and from a neurons cell body.
Through the cytoplasm of its axon = the axoplasm.
Anterograde transport
Transport in the neurone down to the axon tip.
Made possible by kinesis protein
Retrorade transport
Transport in the neurone back to the cell body.
Made possible by the dynein protein.
What is resting membrane potential based on?
Conc. of ions inside + outside of cell.
Describe distribution of ions during resting membrane potential
More sodium ions (Na+) OUTSIDE
More potassium ions (K+) INSIDE.
What are APs?
Temporary shift from negative membrane potential to positive.
Caused by ions flowing in + out of neuron.
What are APs?
Temporary shift from negative membrane potential to positive.
Caused by ions flowing in + out of neuron.
What state are the gated channels in before an AP occurs?
All gated sodium + potassium channels are closed.
What are the 2 types of synapses
Electrical - Mostly bidirectional
Chemical
How much wider is a chemical synapse to an electrical one?
~10 times wider
What are the 2 types of snare proteins in exocytosis?
V-Snare - Vesicle snare proteins
T-Snare - Ones found on the cell membrane.
SYNAPTIC TRANSMISSION - MUSCLE CONTRACTION
Step 1
Nerve impulse arrives at terminal of motor neurone.
ACh leaves neuron via exocytosis.
SYNAPTIC TRANSMISSION - MUSCLE CONTRACTION
Step 2
What happens to the ACh
Diffuses across synaptic cleft
Triggers AP.
SYNAPTIC TRANSMISSION - MUSCLE CONTRACTION
Step 3
Muscle AP travels along transverse tubule = opens Ca2+ channels in SR = Ca2+ into sarcoplasm.
SYNAPTIC TRANSMISSION - MUSCLE CONTRACTION
Step 4
Ca2+ binds to troponin = exposing binding sites for myosin.
SYNAPTIC TRANSMISSION - MUSCLE CONTRACTION
Step 5
Myosin heads bind to actin + initiate power stroke
SYNAPTIC TRANSMISSION - MUSCLE CONTRACTION
Step 6
Ca2+ release channels in SR close + Ca2+ AT pumps use ATP to restore low level of Ca2+ in sarcoplasm.
What are most NTs
aa
Amines (derived from aa)
Peptides
List the NT groups
Cholinergic Neurons
Catecholaminergic Neurones
Serotonergic Neurons
Amino Acidergic neurons
What are cholinergic Neurons
Nerve cells that mainly use ACh to send its messages.
What enzyme is needed to synthesise cholinergic Neurons?
Choline Acetyltransferase
How is ACh synthesised?
Acetyl-CoA + Choline
Choline Acetyltransferase
Which enzymes break down ACh?
Acetylcholine esterase
Name the precursor to catecholaminergic neurons
Tyrosine
Where does serotonin come from?
Tryptophan
Process of tryptophan to serotonin
Tryptophan –(Tryptophan hydroxylase)–> 5-HTP –(Decarboxylase)–> Serotonin
What can low levels of serotonin lead to?
Overproduction of dopamine
What is our memory NT?
Glutamate
What is our calming NT?
Gammaminobutyric acid
List some measurement tools for NM function
Dynamometer
Magnetic Stimulation
Electrical Stimulation
Electromyography
What is a dynamometer used to measure?
Force or strength
What does electromyography measure?
Changes in electrical potential of a muscle.
Can do on the surface of skin or intramuscularly
What is the M wave usually responding to?
Electrical stimulation
What is the M wave representing?
Summation of the muscle AP
== Compound muscle AP
CAMP
Difference between motor evoked potential + the m wave
Motor evoked potential is when we elicit stimulation from the motor cortex.
M wave is elicited from nerve or directly from muscle.
What are the 3 main types of measurements that can be taken in NMF measurements?
Excitability
Contractility
Voluntary Activation
What would come under the excitability measurement?
M-wave amplitude
M-wave area
What would come under the contractility measurement?
Twitch force
Time to peak twitch
Half relaxation time
Electromechanical delay
What do cholinergic Neurons do?
Provide the primary source of ACh to the cerebral cortex + promote cortical activation during wakefulness + rapid eye movement sleep.
