Question

Write a short note on the components of blood.

Answer 1

Blood is a liquid connective tissue composed of plasma and formed elements.

1. Plasma: It forms about 55% of blood and contains about 92% water, plasma proteins, nutrients, hormones, electrolytes and wastes. It transports substances and helps maintain pH, osmotic balance and temperature.
2. Red blood cells: These are numerous, biconcave and non-nucleated in mature humans. Haemoglobin enables them to transport oxygen and some carbon dioxide.
3. White blood cells: These are nucleated cells that protect the body by phagocytosis, antibody formation and other immune responses.
4. Platelets: These are cell fragments formed from megakaryocytes. They collect at injured sites and help form blood clots.

Each component performs a specialised role in transport, defence and protection from blood loss.