Understanding Blood Composition and Its Components

What forms the majority of blood?

A. plasma

B. platelets

C. leukocytes

D. buffy coat

Answer:

The majority of blood is formed by plasma, which includes water, plasma proteins, and other dissolved solutes. It forms the topmost layer observed in a centrifuged blood sample.

When discussing the composition of blood, it is important to understand the role of plasma as the major component. Plasma is a complex liquid component that constitutes the majority of blood volume. It plays a crucial role in maintaining various bodily functions and transporting essential nutrients and waste products throughout the body.

Plasma is primarily composed of water, which makes up about 90% of its volume. In addition to water, plasma also contains various proteins, such as albumin, globulins, and fibrinogen, that are essential for maintaining osmotic pressure, transporting hormones, and aiding in blood clotting processes.

Aside from proteins, plasma also contains other dissolved solutes like glucose, lipids, electrolytes, and gases. These solutes play important roles in energy metabolism, maintaining pH balance, and facilitating gas exchange in the lungs.

When a sample of blood is centrifuged, plasma appears as the lightest and topmost layer, separated from the heavier elements like erythrocytes (red blood cells) by a thin layer known as the 'buffy coat,' which consists of leukocytes (white blood cells) and platelets.

Understanding the composition of blood, particularly the role of plasma, is essential for comprehending how the circulatory system functions and how different components of blood work together to support overall health and well-being.