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In response to a decrease in tissue metabolic activity, tissue oxygen concentrations ________, which causes a(n) ________. In response to a decrease in tissue metabolic activity, tissue oxygen concentrations ________, which causes a(n) ________. increase : active hyperemic response decrease : dilation of the arterioles decrease : increase in tissue ischemia decrease : active hyperemic response increase : constriction of the arterioles

User TimVK
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2 Answers

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Final answer:

Decreased tissue metabolic activity leads to increased oxygen concentrations, which typically results in vasodilation of the arterioles to match the reduced metabolic demands. The myogenic response aids in stabilizing blood flow via vasodilation and vasoconstriction in response to changes in blood pressure and flow.

Step-by-step explanation:

In response to a decrease in tissue metabolic activity, tissue oxygen concentrations increase, which causes a(n) decrease in the demand for blood flow. Therefore, the response is likely to be a dilation of the arterioles to decrease blood flow to the area in order to match the reduced metabolic demand. The myogenic response, which is an intrinsic mechanism of the blood vessels, also contributes to this regulation by relaxing smooth muscle in the vessel walls when there is decreased blood flow or pressure, causing what is known as vasodilation.

Furthermore, decreased tissue metabolic activity and increased oxygen in the tissue can lead to decreased stimulation of the precapillary sphincters, allowing them to relax, thus further contributing to vasodilation. Conversely, if tissue perfusion is too low (ischemia), it leads to low levels of oxygen (hypoxia), which could result in tissue damage if prolonged. The myogenic response helps prevent such extremes by stabilizing blood flow through vasoconstriction when blood flow is high and vasodilation when blood flow is low.

User Hitesh Misro
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Answer:

The correct answer is - increase: constriction of the arterioles.

Step-by-step explanation:

When the physical activity is decreased by the tissues of the muscle, the oxygen concentration in the tissue increases which leads to the constriction of the arterioles.

It takes place in order to decrease blood flow and blood pressure as oxygen requirement is less in the tissue in decreased physical metabolic activity. The constriction of arterioles results in more resistance to decrease the blood flow in capillaries.

User Azog
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