Question

multiple choice question
in skeletal muscles, most of the capillary beds are shut down at rest. which type of vessel is therefore constricted at rest?

veins
venules
arterioles
lymphatic vessels

Explanation:

To solve this, we analyze the function of each vessel:

• Veins carry blood back to the heart; their constriction isn't directly related to shutting down capillary beds.
• Venules collect blood from capillaries; constricting them wouldn't shut down capillary beds initially.
• Arterioles regulate blood flow into capillary beds. Constricting arterioles can shut down capillary beds (as they control the entry of blood into capillaries).
• Lymphatic vessels deal with lymph, not blood flow to capillaries.

So, arterioles are the vessels constricted to shut down capillary beds at rest.

Answer:

C. Arterioles