6. The human circulatory system

Have you ever wondered how all the nutrients that we obtain from food are transported to all the other parts of the body from the digestive system? How the air we respire reaches the various parts of the body from the lungs?

For survival, an organism requires food, water, and oxygen and a system to transport these substances to all the parts of the body for its proper functioning. This system is the circulatory system of the body.

 

Hence, the circulatory system plays a very important role in the functioning of the entire human body.

The circulatory system of humans is a transport system that comprises the network that circulates food, water, and oxygen to the various parts of the body.

It transports respiratory gases, nutrients, hormones and waste products within the body.

 

The circulatory system also protects the body from various harmful pathogens and plays a prominent role in regulating body temperature.

 

 

The three main components that form the circulatory system are:

  

 

  

• Red blood corpuscles or cells (RBCs)
• White blood corpuscles or cells (WBCs)
• Platelets

The red blood cells are produced in the bone marrow. They are red in colour as they contain a red-coloured pigment known as haemoglobin. The blood appears red due to the presence of this pigment.