What are the constituents of blood and their functions?

Constituents of Blood

Blood is composed of several constituents, including:

1. Plasma: Plasma makes up about 55% of blood volume and is primarily composed of water, electrolytes (such as sodium, potassium, chloride, bicarbonate, calcium, and magnesium), nutrients (such as glucose, amino acids, and fatty acids), hormones, waste products (such as urea and creatinine), and proteins (including clotting factors, immunoglobulins, and albumin).

2. Red Blood Cells (Erythrocytes): Red blood cells make up about 45% of blood volume and contain a protein called hemoglobin, which binds to oxygen and transports it from the lungs to tissues and organs.

3. White Blood Cells (Leukocytes): White blood cells make up less than 1% of blood volume and play a crucial role in the immune system by defending the body against infections and diseases. There are several types of white blood cells, including neutrophils, lymphocytes (B cells, T cells, and natural killer cells), monocytes, eosinophils, and basophils.

4. Platelets (Thrombocytes): Platelets make up less than 1% of blood volume and play a vital role in blood clotting by clumping together and forming a temporary plug to stop bleeding.

Functions of Blood Constituents

1. Plasma:

* Maintains blood pressure and fluid balance.

* Transports nutrients, hormones, waste products, and proteins throughout the body.

* Plays a role in immune defense and blood clotting.

2. Red Blood Cells:

* Transport oxygen from the lungs to tissues and organs.

* Remove waste products, such as carbon dioxide, from tissues and transport them back to the lungs.

3. White Blood Cells:

* Defend the body against infections and diseases by attacking foreign invaders, such as bacteria, viruses, and parasites.

* Help recognize and destroy abnormal cells, including cancer cells.

4. Platelets:

* Play a crucial role in blood clotting by stopping bleeding when blood vessels are damaged.

The functions of these constituents work together to maintain homeostasis, transport substances throughout the body, defend against infections, and repair damaged blood vessels, ensuring the proper functioning of the human body.