Plasma Components In Blood & Function

What Is Plasma Made Of?

Plasma is composed mostly of water (about 90–92%) but also contains a mix of important proteins, electrolytes, gases, waste products, nutrients, and hormones. Each of these components has a unique role in keeping the body balanced and functioning properly.

Let’s break it down:

Key Proteins in Blood Plasma

1. Albumin
   The most abundant protein in plasma, albumin helps maintain oncotic pressure, preventing fluid from leaking out of blood vessels. It also binds to hormones, fatty acids, and certain medications, helping transport them through the bloodstream.

2. Antibodies (Immunoglobulins)
   These are the body’s defence agents. Antibodies identify and neutralise harmful invaders like bacteria, viruses, fungi, and abnormal cells such as cancer cells.

3. Clotting Factors
   These proteins are essential for blood clotting. When injury occurs, clotting factors work together to form clots and stop bleeding.

4. Gamma Globulin
   A type of immunoglobulin, gamma globulin plays a key role in the immune response, particularly in fighting infections.

Electrolytes and Mineral Salts in Plasma

1. Chloride
   The main anion (negatively charged ion) in plasma, chloride works alongside sodium to help maintain fluid balance, acid-base homeostasis, and nerve function.

2. Sodium Chloride (Salt)
   As the primary salt in plasma, sodium chloride regulates blood volume, muscle function, and nerve activity.

3. Bicarbonate (HCO₃⁻)
   Crucial for acid-base balance, bicarbonate helps maintain the blood’s pH level and also facilitates the transport of carbon dioxide from tissues to the lungs.

4. Phosphate
   This mineral aids in energy production, supports cell function, and contributes to bone health by regulating calcium metabolism.

5. Iodide
   Found in trace amounts, iodide is absorbed by the thyroid gland to produce thyroid hormones, which are essential for metabolism and growth.

Functions of Plasma

So, what exactly does plasma do?
Its roles are critical and wide-ranging:

• Transports blood cells, nutrients, hormones, and waste products throughout the body

• Regulates blood pressure and circulation

• Maintains pH balance and body temperature

• Supports immune defence through antibodies and immune proteins

• Helps control bleeding via clotting factors

• Carries electrolytes that are vital for heart, nerve, and muscle function

Summary: Why Plasma Matters

• Plasma = 55% of blood volume

• Made up of water, proteins, electrolytes, and nutrients

• Supports transport, protection, pH regulation, and healing

• Plays a central role in homeostasis — the body’s internal balance