The relatively static membrane potential of quiescent cells is called the:
1. | action potential | 2. | threshold potential |
3. | resting membrane potential | 4. | graded potential |
All the following statements regarding the action potential are true except:
1. Only a relatively small number of and ions actually diffuse across the membrane.
2. This event includes both positive and negative feedback loops.
3. The / pumps are directly involved in creating the action potential.
4. During an action potential, the and total concentration are not significantly changed.
A local anesthetic is a medication that causes reversible absence of pain sensation. They:
1. block the closure of voltage regulated potassium ion channels
2. stimulate the opening of voltage regulated potassium ion channels
3. block the opening of the voltage regulated sodium ion channels
4. stimulate the opening of voltage regulated sodium ion channels
What will respectively happen to the synaptic vesicles undergoing exocytosis and the amount of neurotransmitter release as the action potential frequency in a presynaptic neuron increases?
1. increases; increases
2. increases; decreases
3. decreases; increases
4. decreases; decreases
When an excitatory neurotransmitter is released and binds to a receptor on the postsynaptic membrane, the neurotransmitter:
1. stimulates the flow of K+ ions out of the cell
2. produces an EPSP
3. produces an IPSP
4. stimulates the flow of Cl- ions into the cell
When a receptor loses its sensitivity, they are said to be:
1. Summated
2. Transduced
3. Ablated
4. Adaptation
What would be true for the nociceptors?
1. Nociceptors respond to extreme stimuli
2. All nociceptors are located in the skin
3. Nociceptors are involved in noise perception
4. Nociceptor pathways of conduction cannot be inhibited
During accommodation reflex for near vision in the eye there is:
1. increased sympathetic stimulation of iris smooth muscle
2. relaxation of ciliary muscles and lens becomes more spherical
3. increased parasympathetic stimulation leading to relaxation of the ciliary muscles
4. increased parasympathetic stimulation leading to contraction of ciliary muscles
Cataract:
1. is abnormal curvature of cornea
2. is loss of elasticity of the lens
3. occurs often in children
4. involves increased opacity of the lens
A condition in which close objects appear clearly, but far ones don't is called as:
1. Hyperopia
2. Myopia
3. Presbyopia
4. Glaucoma