Roughly speaking, arteries carry blood from the heart and...

Roughly speaking, arteries carry blood from the heart and veins return blood to the heart. From your experience with small cuts or skinned knees, what can you say about the pres- sure in the venous system (veins)? $$\begin{array}{l}{\text { A. It is much less than atmospheric pressure. }} \\ {\text { B. It is slightly more than atmospheric pressure. }} \\ {\text { C. It is approximately the same as atmospheric pressure. }} \\ {\text { D. It is much greater than atmospheric pressure. }} \\ {\text { E. It is slightly greater than atmospheric pressure. }}\end{array}$$

Roughly speaking, arteries carry blood from the heart and veins return blood to the heart. From your experience with small cuts or skinned knees, what can you say about the pres-
sure in the venous system (veins)?
$$\begin{array}{l}{\text { A. It is much less than atmospheric pressure. }} \\ {\text { B. It is slightly more than atmospheric pressure. }} \\ {\text { C. It is approximately the same as atmospheric pressure. }} \\ {\text { D. It is much greater than atmospheric pressure. }} \\ {\text { E. It is slightly greater than atmospheric pressure. }}\end{array}$$

Labs

Want to see this concept in action?

NEW

Explore this concept interactively to see how it behaves as you change inputs.

View Labs

Key Concepts

Venous Pressure

This refers to the blood pressure within the venous system. Compared to the arterial system, the venous pressure is much lower; it is only slightly above atmospheric pressure. This low pressure is sufficient to return blood to the heart without causing rapid or forceful bleeding when veins are injured.

Atmospheric Pressure

Atmospheric pressure is the pressure exerted by the weight of the air in the Earth's atmosphere. It serves as a reference point for comparing blood pressure in the vascular system. In the context of venous pressure, the fact that it is only slightly above atmospheric pressure explains the relatively gentle oozing of blood from small cuts.

Pressure Gradients in Circulation

The pressure gradient, or the difference between the internal pressure of blood vessels and the surrounding atmospheric pressure, is crucial in driving the flow of blood. In veins, the minimal difference means that blood tends to flow slowly, which is why injuries to these vessels result in slow, steady bleeding rather than the forceful spurting seen in arterial injuries.

Transcript

Please give Ace some feedback