active learning session Flashcards
The patient presents with hypokalemia (abnormally low serum potassium level). Which of the following correctly describes the change in neuronal resting membrane potential associated with hypokalemia?
It will become more negative
It will become more positive
It will remain unchanged
It will be more negative
An excitatory postsynaptic potential (EPSP) does which of the following?
Depolarizes a neuron, decreasing the likelihood of an action potential
Hyperpolarizes a neuron, decreasing the likelihood of an action potential
Depolarizes a neuron, increasing the likelihood of an action potential
Hyperpolarizes a neuron, increasing the likelihood of an action potential
Depolarizes a neuron, increasing the likelihood of an action potential
Which of the following can hyperpolarize the resting membrane potential of a neuron?
inward movement of potassium ions
inward movement of sodium ions
inward movement of calcium ions
inward movement of chloride ions
inward movement of water molecules
inward movement of chloride ions
The two-point discrimination test is used to measure integrity of which of the following?
A. Spinothalamic tract
B. Optic nerve
C. Dorsal column-medial lemniscus pathway
D. Fovea
E. Cochlea
C. Dorsal column-medial lemniscus pathway
Which of the following is achieved by acetylcholine release from the sympathetic nerve terminals and stimulation of muscarinic receptors?
A. penile erection
B. stimulation of sweat glands
C. high epinephrine secretion by the adrenal medulla
D. constipation
E. increased heart rate
B. stimulation of sweat glands
(it is the exception to the rule)
Increase in which of the following is the direct effect of beta-2 adrenergic receptors stimulation?
A. blood vessel diameter
B. secretion of sweat by the skin exocrine glands
C. gastric acid secretion
D. secretion of epinephrine (E) by chromaffin cells of the adrenal medulla
A. blood vessel diameter
A 6-year-old boy is brought to the emergency department by his mother. The boy was playing in the yard while she was gardening and ingested some berries. He presents with dilated pupils, blurred vision, dry mouth and elevated heart rate. His symptoms are a result of a chemical in the berries interfering with the normal functioning of the autonomic nervous system. Inhibition of which receptor or enzyme is consistent with the boy’s presentation?
A. Acetylcholinesterase
B. α-Adrenergic receptor
C. β-Adrenergic receptor
D. Muscarinic cholinergic receptor
D. Muscarinic cholinergic receptor
If the effector cell in the diagram below is a pupillary constrictor smooth muscle cell, which of the following receptor types is denoted by structure 6?
A. Alpha1 adrenergic receptor
B. Beta1 adrenergic receptor
C. Beta2 adrenergic receptor
D. M3 cholinergic receptor
E. Nm cholinergic receptor
D. M3 cholinergic receptor
if a patient is suffering from dehydration, which IV fluid can be used to safely rehydrate the patient?
.9% saline solution
The red blood cell intercellular concentration of non penetrating solute is 300 mOsM. NaCl is a non penetrating solute and urea is a penetrating solute for RBC. RBC is placed in the solution of 100 mM NaCl plus 225 mM urea. solution is
hyperosmotic/hypotonic
when the muscles goes from relaxed to contracted, what changes in the sarcomere
H zone decreases in size
what must be displaced so that the myosin head can attach to the actin filament
tropomyosin
what channel opens to release calcium out of the sarcoplasmic reticulum during excitation- contraction coupling
D RYR
during excitation-contraction coupling, what does the SERCA channel transport
Ca 2+
in the muscle fiber, what occurs first when creating an action potential
depolarization
