HUBS 191 Nervous System Latest Update 100% Solved

HUBS 191 Nervous System Latest Update 100% Solved Resting membrane potential -70mV Open Voltage gated ion channels are ? at -60mV Inactive Voltage gated ion channels are ? at+30mV Na+ Extracellular fluid as a high ? concentration and is therefore positive in comparison to the ICF K+ Intercellular fluid has a high ? concentration and is therefore slightly negative in comparison to the ECF Depolarisation The change from a negative resting potential to a positive action potential (caused by opening of sodium channels) Repolarisation The change from a positive action potential back to a negative resting potential (caused by opening of potassium channels) Hyperpolarisation An increase in the potential difference across a cell's membrane, making it more negative than the resting potential. Absolute refractory period The minimum length of time after an action potential during which another action potential cannot propagate Relative refractory period A period after firing when a neuron is returning to its normal polarized state and will fire again only if the incoming message is much stronger and exceeds threshold Excitatory postsynaptic potential A postsynaptic potential that depolarizes the neuronal membrane, making the cell more likely to fire an action potential Able to summate Inhibitory postsynaptic potential A postsynaptic potential that hyperpolarizes the neuronal membrane, making a cell less likely to fire an action potential Able to summate Neuromuscular junctions The association site of axon terminal and the muscle fibre, of which is excitatory and absolute. No summation of EPSP and IPSP. Temporal summation The process in which one synapse continuously fires excitatory potentials, of which add. Spacial summation The process in which multiple synapses simultaneously fire excitatory potentials, adding together. CNS The part of the nervous system that consists of the brain and spinal cord PNS The part of the nervous system that consists of the peripheral nerves Afferent Information that goes into the brain Efferent Response that comes out of the brain Synaptic cleft The narrow gap that separates the presynaptic neuron from the postsynaptic cell. Two The number of neurons in the somatic nervous system Somatic Pertains to the stimuli and responses we are aware of and have control over. Autonomic Pertains to the stimuli and responses we are unaware of and cannot control- involuntary Three The number of neurons in the autonomic nervous system Sympathetic A subdivision of the autonomic nervous system which prepares the body for acute/ stress responses. "Fight or flight" Thoracolumbar exit from CNS. Parasympathetic A subdivision of the autonomic nervous system that prepares the body for rest. "Rest and digest" Craniosacral exit from CNS. Thoracolumbar The level at which the second neuron of the sympathetic nervous system exits the CNS. Craniosacral The level at which the second neuron of the parasympathetic nervous system exits the CNS. Autonomic ganglion Site of the synapse between the axon of the preganglionic neuron and the cell body of the postganglionic neuron between neuron two and three of the autonomic system. Nor epinephrine The neurotransmitter associated