Answer the following statements true (T) or false (F)
1. The papillary muscles contract after the other ventricular muscles so that they can take up the slack on the chordae tendineae before the full force of ventricular contractions sends blood against the AV valve flaps
2. An ECG provides direct information about valve function.
3. As pressure in the aorta rises due to atherosclerosis, more ventricular pressure is required to open the aortic valve.
4. The adjustment of blood flow to each tissue in proportion to its requirements at any point in time is termed autoregulation.
5. Arterial pressure in the pulmonary circulation is much higher than in the systemic circulation because of its proximity to the heart.
1. FALSE
2. FALSE
3. TRUE
4. TRUE
5. FALSE
You might also like to view...
Which of the following are natural analgesics?
A. Endorphins B. Dynorphins C. Enkephalins D. All of the choices are correct.
A stroke is the sudden interruption of the blood supply to the brain.?
Indicate whether the statement is true or false
Choose the correct statement regarding motor units.
A) Muscle fibers of each motor unit are not mingled with those of other motor units. B) During a sustained contraction, all motor units are activated simultaneously. C) A motor neuron may control only two or three muscle fibers of the eye muscle(s). D) When muscles contract for sustained periods, maximal tension is maintained. E) Most motor neurons control fewer than five muscle fibers.
Which of the following statements about enzymes is FALSE?
A. Enzymes are consumed during a chemical reaction. B. Enzymes decrease the free energy of activation of specific reactions. C. Enzymes have unique pH and temperature optima. D. Enzymes increase chemical reaction rates.