MBB1 Flashcards
lecture 1
history of the brain
. adult weight is around 1400 grams
. 3% of our body weight and 20% of our energy resources are found in our brain
. Hippocrates said it was the centre of control
. Galen discovered sensory and muscle nerves
. Vesalius discovered the cortex which is composed of our gyri and sulci and meninges
. Descartes discovered link between the physical brain and non physical mind
. Galvani noticed that there is electricity that occurs with neural communication
. Gall noticed that facial features can be matched to our personality
. Broca discovered that the LFC is the site of expressive language
. Moniz relieved anxiety with Prefrontal leucotomy which is now banned
lecture 2 - M.S and neuron function
- what are symptoms of MS
paraplegia, weakness, numbness, visual problems and slurred speech
- this is because their immune system attacks the myelin sheath that surrounds our axons of neuron disturbing the transmission of action potential/stops communication
lecture 2 - MS and neuron function
- what is the role of myelin sheath?
allows electrical impulses to transmit quickly and efficiently along the nerve cells
lecture 2 - MS and neuron function
-functioning of a cell
. Dendrites allow neurons to communicate
. Axon is a passage that carries signals from the cell body
. Action potential is the signal that gets carried
. Terminal buttons secreted neurotransmitters to either excite or inhibit
. Cytoplasm has mitochondria which uses glucose to produce energy
lecture 2 - MS and neuron function
what does a change in membrane permeability cause?
action potential
lecture 2 - MS and neuron function
4 types of glial cells
- astrocytes which provide physical support and clean up waste to keep the extracellular fluids around cells in good condition
- oligodendrocytes which TOO give physical support but also insulation to axons alongside myelin
- microglia which act as phagocytes
- schwann cells which are like oligodendrocytes but for the PNS
lecture 2 - MS and neuron function
depolarisation
…occurs when a positive electrical current passes through making the sodium channels open
…membrane potential goes from a negative charge to a positive
…the current must be between -70mvs to 40mvs
lecture 2 - MS and neuron function
repolarisation
…occurs after depolarisation and potassium channels now open to bring back a balance as there is too much positive potassium now in the axon
lecture 2 - MS and neuron function
refractory period
…occurs when sodium channels close and cannot re open until the membrane reaches its resting potential again which is -70mvs
lecture 2 - MS and neuron function
role of the sodium potassium pump
…allows a cell to have both sodium and potassium inside during the change in membrane potential which is crucial for normal functioning
lecture 2 - MS and neuron function
hyperpolorisation
…potassium ions start to move out and the process of action potential can start again
lecture 2 - MS and neuron function
what medicine can be administered to allivieate MS
interferon b - aids the Nodes of Ranvier which have been disrupted
lecture 2 - MS and neuron function
what are the advantages of the action potential jumping along myelinated axons
1 it saves energy
2 it increases the speed therefore our reaction time is faster
lecture 2 - MS and neuron function
where are sodium ions most concentrated?
…outside of the neuron making the membrane potential more positive
…efflux of potassium however makes the membrane potential more negative
lecture 3
what is myasthenia gravis?
…a disorder of synaptic transmission
lecture 3
steps of neurotransmitter release
- enzymes
- NT release from the top
- NT binds to vesicles
- some enzymes degrade
- those that haven’t leave the pre synapse and attach to the post synaptic receptor
lecture 3
EPSP vs IPSP
EPSP - depolorises the postsynaptic cell and increases the chance of an action potential
IPSP - hyperpolorises the postsynaptic cell and decreases the chances of an action potential
lecture 3
what is reuptake?
occurs in the synaptic cleft and ensure there are no lingering NTs that did not make it into the postsynapse