The Sinoatrial Node, or Cardiac Pacemaker, Is ________

question 121

Multiple Choice

The sinoatrial node, or cardiac pacemaker, is ________.

• A) electrically active nodal tissue located in the wall of the left ventricle
• B) embedded in the anterior two-thirds of the interventricular septum
• C) able to cause the atria and ventricles to contract simultaneously
• D) able to cause the cardiac muscle to begin to contract at the apex
• E) embedded in the posterior wall of the right atrium, near the entrance of the superior vena cava

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Definitions:

Consumer Surplus

The gap between the total price consumers are ready and able to pay for a good or service versus what they actually spend.

Producer Surplus

The difference between the amount a producer is willing to accept for a good or service versus what they actually receive, usually resulting from market prices above minimum selling prices.

Deadweight Loss

The loss of economic efficiency that can occur when the free market equilibrium for a good or a service is not achieved, leading to a loss of total welfare or economic surplus.

Price Ceilings

Regulatory measures that set a maximum price that can be charged for a product or service, intended to protect consumers from excessive pricing.