Interstitial fluid

Definition

Interstitial fluid is the fluid that surrounds and bathes the cells in tissues. It plays a crucial role in transporting nutrients, gases, and waste products between cells and the bloodstream.

5 Must Know Facts For Your Next Test

1. Interstitial fluid makes up a significant portion of extracellular fluid, which also includes plasma.
2. It helps maintain homeostasis by facilitating nutrient and gas exchange at the cellular level.
3. The composition of interstitial fluid is similar to plasma but with lower protein concentrations.
4. Lymphatic vessels collect excess interstitial fluid and return it to the bloodstream to prevent tissue swelling (edema).
5. Osmoregulation processes ensure that the balance of water and electrolytes in interstitial fluid remains stable.

Review Questions

• What is the primary function of interstitial fluid in the body?
• How does interstitial fluid differ from plasma in terms of protein content?
• Explain how the lymphatic system interacts with interstitial fluid.

Related terms

Extracellular Fluid: Fluid outside of cells, including both interstitial fluid and plasma.

Homeostasis: The body's ability to maintain stable internal conditions despite external changes.

Osmoregulation: The process by which organisms regulate water balance and electrolyte concentration within their bodies.