Functions and Composition of Blood

Functions of Blood

• Blood plays crucial roles in homeostasis, including temperature regulation, pH balance, and fluid balance.
• It transports oxygen from the lungs to cells and carbon dioxide from cells back to the lungs.
• Nutrients, hormones, and waste products are carried by blood, connecting various body systems.
• Blood provides immune defense via white blood cells, protecting against pathogens.
• Clotting factors in blood facilitate healing processes to prevent excessive blood loss.

Composition of Blood

• Blood consists of formed elements and plasma.
• Formed elements include:
  • Red blood cells (RBCs), which lack a nucleus (anucleated) and are essential for oxygen transport.
  • White blood cells (WBCs), integral for immune responses and pathogen defense.
  • Platelets, small cell fragments that aid in clotting.
• Plasma is the liquid portion of blood, making up about 55% of total blood volume, containing water, electrolytes, proteins, hormones, and wastes.

Physical Characteristics of Whole Blood

• Blood is typically viscous and has a metallic taste due to iron in hemoglobin.
• Color ranges from bright red (oxygenated) to dark red (deoxygenated), depending on oxygen saturation.
• Normal blood volume is approximately 5-6 liters in an adult, accounting for about 7-8% of body weight.

Blood Separation Using a Centrifuge

• A centrifuge spins blood samples at high speeds, separating components based on density.
• Separation results in:
  • Plasma at the top layer.
  • A thin layer called the Buffy coat, containing WBCs and platelets.
  • Packed RBCs at the bottom, which are the heaviest components.

Hematocrit

• The percentage of packed RBCs in blood is referred to as hematocrit.
• Normal hematocrit levels range from 38% to 52% in males and 36% to 48% in females, indicating adequate red cell mass.

Components of Plasma

• Plasma is primarily composed of water (90-92%), serving as a solvent and medium for transporting substances.
• Key proteins in plasma include:
  • Albumin, which helps maintain osmotic pressure and transport various substances.
  • Globulins, including antibodies that play a role in immune response.
  • Fibrinogen, a key component in the clotting process.
• Electrolytes, hormones, waste products, and nutrients are also present to support bodily functions and homeostasis.

Explore the critical functions and components of blood in this quiz. Test your knowledge on how blood contributes to homeostasis, transports essential substances, and aids in immune defense and healing. Learn about the various elements that make up blood and their specific roles.