As soon as left ventricular pressure exceeds the pressure in the aorta, the
A. aortic semilunar valve opens.
B. atria pump blood into the ventricles.
C. ventricles pump blood into the atria.
D. pulmonary semilunar valve closes.
E. AV valves open.
Answer: A
You might also like to view...
Which of the following statements related to the "ON pathway" of the visual system is correct?
A. Bipolar cells spontaneously depolarize in the absence of input from photoreceptor cells. B. Glutamate receptors on bipolar cells are excitatory. C. Only cones are associated with bipolar cells of the "ON pathway," rods are not. D. Bipolar cells fire action potentials only when bright light strikes the photoreceptors linked to them. E. Bipolar cells hyperpolarize in the absence of input from photoreceptor cells.
Which of the following signs of hypovolemic shock is a relatively late sign?
A) cold, clammy skin B) increased heart rate C) rapid, thready pulse D) rapidly falling blood pressure
Intravenous infusion of 2 L of which of the following solutions will lead to the largest increase in ICF volume?
A. D5W B. isotonic NaCl C. hypotonic NaCl D. hypertonic NaCl
Which of these does not contribute to the cessation of the signal in a synaptic transmission?
A) Neurotransmitter escapes from the synapse into the nearby extracellular fluid. B) The synaptic knob reabsorbs some neurotransmitters by endocytosis. C) Synaptic vesicles secrete neurotransmitter by exocytosis. D) Neurotransmitters are no longer released. E) Enzymes in the postsynaptic cell break down some neurotransmitters.