Immediately following the P wave of the electrocardiogram, an A wave appears on both the left and right heart pressure graphs. This A wave corresponds to which of the following?

a. Atrial contraction
b. Atrioventricular valve closure
c. Semilunar valve closure
d. Ventricular contraction


ANS: A
The P wave signals atrial depolarization. Within 0.1 sec, the atria contract, causing a slight rise in both atrial and ventricular pressures (the A waves).

Health Professions

You might also like to view...

It is appropriate to control the filling of an evacuated blood-collection tube manually.

Answer the following statement true (T) or false (F)

Health Professions

How much weight is given to the evidence and testimony is known as the __________ of Proof

Fill in the blank(s) with the appropriate word(s).

Health Professions

Which of the following is the appropriate way for the medical assistant working in a physician's office to leave a message for patients at their place of employment? 

A. Leave the medical assistant's name and phone number only B. Leave the physician's name and phone number only C. Leave a message with phone numbers for both the medical assistant and the physician D. Leave a detailed message so the patient does not need to return the call E. Leave a message that the patient's doctor's office is calling

Health Professions

The superior, middle, and inferior conchae extend medially from the lateral masses of the ethmoid bone

Indicate whether the statement is true or false

Health Professions