Asked by Ranju Guragain on Jun 29, 2024
Verified
Which of the following is not true of the respiratory pump?
A) It is a mechanism that helps with venous return to the heart.
B) Contraction of the diaphragm causes an increase in the volume of the thoracic cavity, and a decrease in pressure.
C) Increased venous return to the heart causes the heart rate to increase.
D) More blood enters the heart during expiration than inspiration.
E) All of these are true of the respiratory pump.
Respiratory Pump
A mechanism involving the muscles of the thorax and abdomen, which helps in moving air in and out of the lungs during breathing.
Diaphragm
a large, dome-shaped muscle located at the base of the lungs that plays a crucial role in breathing.
Venous Return
The flow of blood back to the heart through the veins, crucial for maintaining cardiovascular circulation.
- Describe the mechanisms and significance of venous return in cardiovascular health.
Verified Answer
KM
Kaniya morrisJul 04, 2024
Final Answer :
D
Explanation :
The statement "More blood enters the heart during expiration than inspiration" is not true. During inspiration, the decrease in thoracic pressure creates a vacuum that helps draw blood back to the heart, resulting in increased venous return. Therefore, more blood enters the heart during inspiration than expiration.
Learning Objectives
- Describe the mechanisms and significance of venous return in cardiovascular health.