Procaine (Novocain) is a drug that blocks voltage-gated Na+ channels. When present, what would happen in a neuron?
A. Neither graded potentials nor action potentials will occur.
B. Graded potentials are possible, but the neuron will not have the depolarizing phase of the action potential.
C. Graded potentials are possible and the neuron will have the depolarizing phase of the action potential, but will be unable to repolarize.
D. No phase of the action potential will be affected.
Answer: B
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Regarding the relationships between the rates of oxygen consumption/carbon dioxide production and alveolar ventilation, which of these statements is TRUE?
A. Increased ventilation without a similar increase in metabolism is called hypoventilation. B. In hypoventilation, alveolar PCO2 decreases below resting levels. C. In hyperventilation, alveolar PCO2 can decrease to zero. D. A decrease in metabolism without a similar decrease in alveolar ventilation would result in hyperventilation. E. An increase in ventilation with a matching increase in metabolism is called hyperventilation.
One of the organic substances not normally excreted by the kidney is __________.
a) uric acid b) glucose c) urea d) creatinine
What secondary brain vesicles form from the forebrain?
A) diencephalon and telencephalon B) telencephalon and metencephalon C) metencephalon and mesencephalon D) metencephalon and myelencephalon
A decrease in blood oxygen increases the release of ________ from kidneys and liver, and it stimulates the production of ________ by red bone marrow.
A. erythropoietin; leukocytes B. folic acid; erythrocytes C. erythropoietin; erythrocytes D. folic acid; leukocytes