A drug that decreased calcium levels in a muscle cell and thereby lowered the number of crossbridges formed during the heart's contractions would be a
A. positive chronotropic agent.
B. positive inotropic agent.
C. negative inotropic agent.
D. negative chronotropic agent.
Answer: C
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Diapedesis is the process by which red blood cells move into tissue spaces from the interior of blood capillaries
Indicate whether the statement is true or false
Which of the following is not true of inspiration?
A. Inspiratory reserve volume is much lower than expiratory reserve volume. B. Enlargement of the thoracic cavity reduces the pressure in the lungs, leading to air entering the thoracic cavity. C. Inspiration results from contraction of the diaphragm and the external intercostal muscles. D. The anatomic dead space is about 30% of the inhaled tidal volume. E. All of these are true of inspiration.
As blood is pumped from the left ventricle, it passed through the _____.
A) ductus arteriosus B) tricuspid valve C) mitral valve D) aortic semilunar valve E) pulmonary semilunar valve
When the urinary bladder is filled with 200-400 ml of urine, micturition reflex sends ________ action potentials to cause the ________ urethral sphincter to open (relax).
A. sympathetic; internal B. sympathetic; external C. parasympathetic; internal D. parasympathetic; external