HUBS 191 Nervous System Exam Questions and Answers |100% Verified and Updated 2024

HUBS 191 Nervous System Exam Questions and Answers |100% Verified and Updated 2024 Resting membrane potential -Answer--70mV Open -Answer-Voltage gated ion channels are ? at -60mV Inactive -Answer-Voltage gated ion channels are ? at+30mV Na+ -Answer-Extracellular fluid as a high ? concentration and is therefore positive in comparison to the ICF K+ -Answer-Intercellular fluid has a high ? concentration and is therefore slightly negative in comparison to the ECF Depolarisation -Answer-The change from a negative resting potential to a positive action potential (caused by opening of sodium channels) Repolarisation -Answer-The change from a positive action potential back to a negative resting potential (caused by opening of potassium channels) Hyperpolarisation -Answer-An increase in the potential difference across a cell's membrane, making it more negative than the resting potential. Absolute refractory period -Answer-The minimum length of time after an action potential during which another action potential cannot propagate Relative refractory period -Answer-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 -Answer-A postsynaptic potential that depolarizes the neuronal membrane, making the cell more likely to fire an action potential Able to summate Inhibitory postsynaptic potential -Answer-A postsynaptic potential that hyperpolarizes the neuronal membrane, making a cell less likely to fire an action potential Able to summate Neuromuscular junctions -Answer-The association site of axon terminal and the muscle fibre, of which is excitatory and absolute. No summation of EPSP and IPSP. Temporal summation -Answer-The process in which one synapse continuously fires excitatory potentials, of which add. Spacial summation -Answer-The process in which multiple synapses simultaneously fire excitatory potentials, adding together. CNS -Answer-The part of the nervous system that consists of the brain and spinal cord PNS -Answer-The part of the nervous system that consists of the peripheral nerves Afferent -Answer-Information that goes into the brain Efferent -Answer-Response that comes out of the brain Synaptic cleft -Answer-The narrow gap that separates the presynaptic neuron from the postsynaptic cell. Two -Answer-The number of neurons in the somatic nervous system Somatic -Answer-Pertains to the stimuli and responses we are aware of and have control over. Autonomic -Answer-Pertains to the stimuli and responses we are unaware of and cannot control- involuntary Three -Answer-The number of neurons in the autonomic nervous system Sympathetic -Answer-A subdivision of the autonomic nervous system which prepares the body for acute/ stress responses. "Fight or flight" Thoracolumbar exit from CNS. Parasympathetic -Answer-A subdivision of the autonomic nervous system that prepares the body for rest. "Rest and digest" Craniosacral exit from CNS. Thoracolumbar -Answer-The level at which the second neuron of the sympathetic nervous system exits the CNS. Craniosacral -Answer-The level at which the second neuron of the parasympathetic nervous system exits the CNS. Autonomic ganglion -Answer-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 -Answer-The neurotransmitter associated with the sympathetic nervous system. Acetylcholine -Answer-The main neurotransmitter of the nervous system besides that of the sympathetic nervous system.