Q:

What is the function of an arteriole?

A:

Quick Answer

Arterioles facilitate and manage the flow of blood between the oxygen-rich arterial component of the circulatory system and the oxygen-poor venous loop. Dictionary.com describes arterioles as the smallest branches of an artery and notes that they terminate in capillary beds.

Continue Reading

Full Answer

About.com Biology provides details about how arterioles function to encourage the circulation of oxygen-rich blood to the parts of the body that need it most. Each arteriole is equipped with a special valve, the precapillary sphincter, that opens and closes in response to the flexure and contraction of its tiny internal muscle. When open, these valves permit blood to flow out of the arterioles and into the capillary beds where gas and waste exchange can take place. When these valves are closed, arterial blood flows past the capillaries and directly into the venules through a structure called the thoroughfare channel. This has the effect of bypassing the surrounding tissue bed and shunting oxygen-rich blood to other areas of the body where it might be more urgently needed. An example of this process is the rerouting of blood to the digestive organs which arterioles undertake to improve the breakdown and absorption of nutrients from food. While blood is present in all parts of the body at all times, the capillary beds only contain blood when it is needed.

Learn more about Blood

Related Questions

  • Q:

    How often does blood circulate through the body?

    A:

    According to Santa Barbara City College, for an average person, the entire volume of blood in the circulatory system is pumped through the heart approximately once per minute. The average person has 5 liters of blood in their circulatory system and a cardiac output of 4.9 liters per minute.

    Full Answer >
    Filed Under:
  • Q:

    How do you read a blood flow diagram?

    A:

    All of the blue-colored blood vessels on a blood flow diagram show passages carrying deoxygenated blood from the heart to the lungs, while all of the red-colored passages show oxygenated blood being circulated throughout the body. The heart's right chambers pump deoxygenated blood, while the left chambers pump oxygenated blood.

    Full Answer >
    Filed Under:
  • Q:

    How do you trace the flow of blood through the heart?

    A:

    The flow of blood through the heart can be traced by injecting a dye into the arteries through a procedure known as an angiogram. Another procedure, cardiac catheterization, involves using a catheter to inject the dye. Magnetic resonance angiography or MRA, uses MRI technology.

    Full Answer >
    Filed Under:
  • Q:

    What are both lymph and venous blood flow heavily dependent on?

    A:

    Lymph flow is highly dependent on the contraction of skeletal muscles and pressure alterations during breathing. Similarly, venous blood flow relies on breathing movements and contraction of skeletal muscles, "Hole’s Human Anatomy and Physiology" explains.

    Full Answer >
    Filed Under:

Explore