Neurophysiology Exam Questions and Correct Answers (Rated A+) Already Passed

Neurophysiology Exam Questions and Correct Answers (Rated A+) Already Passed Which of these barriers would return an electric potential reading on voltmeter? a) Porous b) Selectively permeable - Answers selectively permeable ______________________ describes the electrical potential across the cell membrane that a single ion would produce if the membrane were permeable to only that ion - Answers Nernst potential ______________________ equation predicts the membrane potential that results from the contribution of all ions that can cross the membrane - Answers GHK What is the resting membrane potential? - Answers -70mV Where is sodium concentration higher? - Answers ECF Where is potassium concentration higher? - Answers ICF What has greater leak channels? K or Na? - Answers K Dendrites contain ______________________-______________________ ______________________ channels - Answers mechanically gated sodium An increase in ECF Na+ concentration will ______________________ the neurons - Answers shrink An axon of first order somatosensory neuron is stimulated in a laboratory with a 25mV pulse, which initiates an action potential with a velocity of 100 meters per second. The axon is then stimulated with a 200mV. What is the action potential velocity after the 200-mV pulse (in meters per second)? - Answers 100 Which of the following would not lead to inappropriate patellar reflex response in a clinical exam? (letter only) A) a damage to the efferent lower motor neuron innervating quadriceps B) a damage to the efferent somatic motor neuron innervating hamstring C) a damage to the interneuron synapsing on the lower motor neuron to hamstring D) a damage to the upper motor neuron descending from the motor cortex E) a damage to the somatosensory neuron synapsing on motor neuron innervating quadriceps - Answers D You are given that the salivary glad (target organ) is regulated by parasympathetic nervous system activity. Which of the following is not true? (letter only) A) The parasympathetic autonomic ganglion is located close to the salivary gland B) The neurotransmitter released from the post-ganglionic fiber to salivary gland is acetylcholine C) Parasympathetic receptors in the salivary gland cannot be inhibited by an adrenergic receptor blocker D) Muscarinic receptor blocker would inhibit the effects of parasympathetic nervous system activity E) The receptor located on the cell body of the post-ganglionic fiber is muscarinic - Answers E This is also known as the trigger zone of the neuron - Answers Axon hillock This coating of the axon will increase the speed of the action potential - Answers myelin These are the spaces in the myelin sheaths - Answers nodes of Ranvier ______________________ potential is caused by the sodium that flows through the mechanically gated sodium channels in the dendrites. - Answers Graded ______________________ ______________________is caused by the voltage-gated sodium channels - Answers action potential During the ______________________ refractory period, the voltage gated sodium channels will not respond to another stimulus - Answers absolute During the ______________________ refractory period, another action potential can occur if the stimulus is high enough - Answers relative The action potential reaches the end of the axon. This part of the axon is called the ______________________ ______________________ - Answers axon terminus What is the space between upstream and downstream neurons? - Answers Synaptic cleft What types of channels are found in the axon terminus? - Answers Voltage-gated calcium channels The concentration of calcium is higher in the ECF or ICF? - Answers ECF The process of vesicles releasing their neurotransmitters is called ______________________ - Answers Exocytosis Acetylcholine is (excitatory/inhibitory) - Answers excitatory GABA is inhibitory or excitatory? - Answers inhibitory If ACh binds with the receptor in the downstream neuron in the synaptic cleft, what ion flows into the cell? - Answers Na+ If GABA binds with the receptor in the downstream neuron in the synaptic cleft, what ion flows into the cell? - Answers Cl- An EPSP is ______________________ - Answers depolarizing An IPSP is ______________________ - Answers hyperpolarizing If the same excitatory neuron releases two potentials quickly, this summation is called ______________________ ______________________ - Answers Temporal summation If two different excitatory neurons release potentials at the same time, this summation is called ______________________ ______________________ - Answers Spatial summation ______________________ respond to the stimulus of pressure - Answers mechanoreceptors ______________________ respond to changes in temperature - Answers thermoreceptors ______________________ respond to pain - Answers nociceptors Pain, pressure, and temperature follow a ______________________, where the brain associates a signal from a specific sensory receptor with a special part of the somatosensory cortex. - Answers modality The ability to differentiate between two pins on the skin is known as ______________________-______________________ ______________________ - Answers two-point discrimination For fine touch, proprioception, and vibration, the primary sensory neuron synapses in the ______________________ - Answers medulla When the sensory neuron moves across the midline of the body, it's known as ______________________ - Answers decussation Where does the somatosenory neuron of temperature decussate? - Answers spinal cord On the skeletal muscle, what type of receptor is found in the motor endplate? - Answers Nicotinic Which adrenergic receptor is found in most sympathetic target tissues? - Answers Alpha 1 Alpha 1 receptors are more sensitive to ______________________ - Answers norepinephrine