Heart, Circulation & Blood: What do they actually do?

Heart, Circulation & Blood: What do they actually do?


The human heart is made up of four chambers, each with intricacies that serve a crucial purpose to our bodies. Our hearts consist of two upper left and right atrium chambers, and two lower left and right ventricle chambers. The right atrium receives blood from the body that is low in oxygen and pumps it through to the right ventricle; the right ventricle then pumps the low oxygen blood into the lungs. As we use our lungs to breathe in, our left atrium receives blood that is high in oxygen from the lungs, then pumps the blood through to the left ventricle; the left ventricle is then able to pump high oxygen blood into our body.

Circulatory System

Between the blood passing in and out of the heart, our blood passes through an extremely intricate infrastructure of systemic and pulmonary components, otherwise known as our circulatory system. Both components of our circulatory systems are synergised to maintain normal bodily function. Our pulmonary system is otherwise known as our respiratory system, relating directly to the lungs and oxygen distribution around the body. Our heart relies on the pulmonary system to enrich our blood with oxygen and to exhale the carbon dioxide generated from our exhausted blood. We rely on our systemic circulatory routes not only to distribute our oxygen and nutrients to our body tissues, but also to pick up our carbon dioxide and exhausted blood for our pulmonary system to process. Our blood is cycled through our body; oxygenated blood is pumped into our arteries from our left ventricle, from our arteries to our capillaries within our body tissue, then returned to our right atrium through a system of veins.


Our blood consists of plasma and red blood cells; plasma carries nutrients such as vitamins, minerals, amino acids, fatty acids and glucose, whereas red blood cells transport oxygen and carbon dioxide around our body. Both are essential to keep our organs, muscles and immune system functioning.