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 49 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?

When blood is exposed to air, it clots. Heparin allows the blood to come in direct contact with air without clotting.

Did you know?

The use of salicylates dates back 2,500 years to Hippocrates’s recommendation of willow bark (from which a salicylate is derived) as an aid to the pains of childbirth. However, overdosage of salicylates can harm body fluids, electrolytes, the CNS, the GI tract, the ears, the lungs, the blood, the liver, and the kidneys and cause coma or death.

Did you know?

The average adult has about 21 square feet of skin.

Did you know?

Complications of influenza include: bacterial pneumonia, ear and sinus infections, dehydration, and worsening of chronic conditions such as asthma, congestive heart failure, or diabetes.

Did you know?

People with high total cholesterol have about two times the risk for heart disease as people with ideal levels.

For a complete list of videos, visit our video library