Plasma

Definition

Plasma is the liquid component of blood that carries cells, nutrients, hormones, and waste products throughout the body. Comprising about 55% of total blood volume, plasma plays a crucial role in maintaining blood pressure and volume, as well as transporting essential substances needed for bodily functions.

5 Must Know Facts For Your Next Test

1. Plasma is composed of approximately 90% water, making it an effective solvent for transporting various substances throughout the body.
2. In addition to water, plasma contains proteins such as albumin, globulins, and fibrinogen, which are vital for maintaining osmotic pressure and immune responses.
3. The pH level of plasma is tightly regulated to maintain homeostasis, typically ranging from 7.35 to 7.45.
4. Plasma also transports waste products like urea and creatinine to the kidneys for excretion.
5. During periods of dehydration or blood loss, the body can adjust plasma volume by redistributing fluids from other compartments to maintain circulation.

Review Questions

• How does plasma contribute to homeostasis within the cardiovascular system?
  • Plasma helps maintain homeostasis by regulating blood pressure and volume through its composition and the proteins it contains. The presence of proteins like albumin ensures proper osmotic pressure, which influences fluid movement between blood vessels and tissues. Additionally, plasma transports hormones and nutrients necessary for cellular function, ensuring that tissues receive what they need to maintain equilibrium.
• Discuss the role of plasma proteins in immune response and clotting processes.
  • Plasma proteins such as immunoglobulins play a critical role in immune response by identifying and neutralizing pathogens. Fibrinogen is essential for blood clotting; when activated, it forms fibrin threads that create a mesh to stop bleeding. This interaction between plasma proteins ensures that the body can respond quickly to injuries and infections, highlighting their importance in protecting health.
• Evaluate how changes in plasma composition might affect overall health and disease processes.
  • Changes in plasma composition can significantly impact overall health and contribute to various disease processes. For instance, elevated levels of certain proteins may indicate inflammation or infection, while low albumin levels can signal liver dysfunction or malnutrition. Additionally, imbalances in electrolytes can lead to issues such as arrhythmias or muscle cramps. Understanding these changes helps in diagnosing conditions and tailoring treatments effectively.

Related terms

Red Blood Cells: Cells in the blood that carry oxygen from the lungs to the rest of the body and return carbon dioxide back to the lungs.

Platelets: Small cell fragments in the blood that play a key role in clotting and wound healing.

Electrolytes: Minerals in plasma that help regulate fluid balance, muscle contractions, and nerve function.