This topic contains a solution. Click here to go to the answer

Author Question: In most patients, the sinoatrial (SA) and atrioventricular (AV) nodes are supplied by the _____ ... (Read 22 times)

pane00

  • Hero Member
  • *****
  • Posts: 579
In most patients, the sinoatrial (SA) and atrioventricular (AV) nodes are supplied by the _____ coronary artery.
 
  a. right
  b. left main
  c. circumflex
  d. left anterior descending

Question 2

Stimulation of beta2 receptor sites results in _____.
 
  a. increased heart rate
  b. peripheral vasoconstriction
  c. constriction of renal blood vessels
  d. relaxation of bronchial smooth muscle



Related Topics

Need homework help now?

Ask unlimited questions for free

Ask a Question
Marked as best answer by a Subject Expert

Sammyo

  • Sr. Member
  • ****
  • Posts: 329
Answer to Question 1

A
The SA node receives its blood supply from the SA node artery that runs lengthwise through the center of the node. The SA node artery originates from the right coronary artery in about 60 of people. The AV node is supplied by the right coronary artery in 85 to 90 of the population. In the remainder, the circumflex artery provides the blood supply.

Answer to Question 2

D
Beta2 receptor sites are found in the arterioles of the heart, lungs, and skeletal muscle. Stimulation results in dilation. Stimulation of beta2 receptor sites in the smooth muscle of the bronchi results in dilation.





 

Did you know?

Before a vaccine is licensed in the USA, the Food and Drug Administration (FDA) reviews it for safety and effectiveness. The CDC then reviews all studies again, as well as the American Academy of Pediatrics and the American Academy of Family Physicians. Every lot of vaccine is tested before administration to the public, and the FDA regularly inspects vaccine manufacturers' facilities.

Did you know?

The average human gut is home to perhaps 500 to 1,000 different species of bacteria.

Did you know?

Liver spots have nothing whatsoever to do with the liver. They are a type of freckles commonly seen in older adults who have been out in the sun without sufficient sunscreen.

Did you know?

More than nineteen million Americans carry the factor V gene that causes blood clots, pulmonary embolism, and heart disease.

Did you know?

The modern decimal position system was the invention of the Hindus (around 800 AD), involving the placing of numerals to indicate their value (units, tens, hundreds, and so on).

For a complete list of videos, visit our video library