Which of the following helps return blood to the heart?
A)Positive intrathoracic pressure
B)Valves in the arteries
C)Contracting skeletal muscles
D)Capillary action

Question

Quizplus · Accepted Answer

Contracting skeletal muscles help return blood to the heart. As the muscles contract and relax, they squeeze the veins and help push blood towards the heart. Valves in the veins also prevent blood from flowing back down due to gravity. Positive intrathoracic pressure occurs during inhalation and helps draw blood into the thoracic cavity, but does not directly assist in returning blood to the heart. Capillary action occurs in tiny capillaries and helps move fluid and nutrients between blood vessels and body tissues, but does not actively return blood to the heart.

Which of the Following Helps Return Blood to the Heart