In an EKG, the P wave is generated when the
| A. | ventricles repolarize. |
| B. | atria depolarize. |
| C. | atria repolarize. |
| D. | ventricles depolarize. |
Which of the following does NOT contribute to venous bloodpressure?
| A. | constriction of smooth muscle around veins by the sympatheticnervous system |
| B. | increased abdominal pressure during breathing |
| C. | venous anastomoses |
| D. | skeletal muscle activity |
Blood flow is ________ proportional to the difference in bloodpressure. Blood flow is ________ proportional to the totalperipheral resistance.
| A. | directly; directly |
| B. | directly; inversely |
| C. | inversely; inversely |
| D. | inversely; directly |
