[Campbell Biology P.982] According to Figure 42.14 and the accompanying text, which statemen... | Practice Question

According to Figure 42.14 and the accompanying text, which statement accurately describes the forces driving net fluid movement out of a capillary?

  • A: Net fluid movement out occurs when blood pressure is greater than osmotic pressure, as is typically the case along the entire length of the capillary shown.
  • B: Osmotic pressure drives fluid out of the capillaries, while blood pressure draws it back in.
  • C: Fluid loss only occurs at the arterial end where blood pressure is highest, and fluid is recovered at the venous end.
  • D: The net fluid movement into the interstitial fluid is balanced by an equal return of fluid into the capillaries.

Explanation

Figure 42.14 and its description indicate a hypothetical capillary where blood pressure consistently exceeds osmotic pressure, resulting in a net movement of fluid out into the interstitial fluid along its entire length. The text also states that 'blood pressure is greater than the opposing forces, leading to a net loss of fluid from capillaries' on average, emphasizing that the lymphatic system is needed to recover this lost fluid.