Chapter 17 - Control of Cardiovascular Function Flashcards
What is the main function of the cardiovascular system?
Transport.
What is another name for pulmonary circulation?
Central circulation.
What is another name for systemic circulation?
Peripheral circulation.
Which side of the heart belongs to the pulmonary circulation?
The right side of the heart.
Which side of the heart belongs to the systemic circulation?
The left side of the heart.
Why is the pulmonary system lower pressure than the systemic system?
It is a shorter circuit, and lies closer to the heart. Also, moving blood slowly through the lungs allows more time for gas exchange.
Why is the systemic system higher pressure than the pulmonary system?
The blood has further to go, and often works against gravity.
How is the direction of blood flow through the heart controlled (to prevent backflow)?
By two sets of valves that act reciprocally. (i.e. one set opens while the other closes).
Both sides of the heart must eject the same amount of blood with each beat in order to prevent blood from accumulating in either the pulmonary or systemic circulation. However, there is almost always a slight variation in the amount of blood pumped by each side of the heart. What accommodates these variations and prevents accumulation of blood?
The venous system has large storage capabilities that allow for temporary small changes in blood volume.
Why must the output of the left and right heart be the same?
Because the circulation is a closed system.
What two things are needed in order to have blood flow in the circulatory system?
Blood volume that is sufficient to fill the blood vessels, and a pressure gradient that is sufficient to move the blood forward.
Which blood vessels have the highest pressure?
The arteries and arterioles.
Which blood vessels contain the smallest volume of blood, and why?
The capillaries, because they have a very small size and large surface area.
What is the function of the veins?
They serve as a reservoir to collect blood from the capillaries and return it to the right side of the heart.
What provides the driving force for blood flow in the systemic circulation?
The pressure difference between arteries and veins.
