Human Circulatory System

In this last week I will write about a body system that is very important to us. This system is very necessary for the human being because it is responsible for transporting oxygen and nutrients to cells. Further, removes their (cells) metabolic wastes that must later be removed by the kidneys, urine, and exhaled air in the lungs, rich in carbon dioxide. This system is called Circulatory System. The Circulatory System consists of the heart and blood vessels, including veins, arteries and capillaries.

Blood is the fluid that circulates throughout the body through the Circulatory System. It is a fluid tissue, consisting of water and organic and inorganic substances (minerals) dissolved, forming blood plasma and three types of blood cells or cellular components: red cells, white cells and platelets. A drop of blood contains about 5 million red blood cells, white blood cells 5,000-10,000 and about 250,000 platelets. All these cells have a specific function in our body for example, the red blood cells are responsible for the distribution of molecular oxygen, the white blood cells (leukocytes) have an important role in the immune system to perform cleanup work (phagocytes) and defense (lymphocytes), also you can click on immune system to see more information about this system, and the platelets are fragments of very small cells, used to plug wounds and prevent bleeding. Nevertheless, the heart is the main organ of the Cardiac System and one of the most important human being.

The heart is a muscular organ responsible for receiving and pumping blood so that it circulates throughout the body, about a 60 to 100 time per minute. This organ consists mainly in a muscle called myocardium or heart muscle, and inside of the heart are found four chamber: two atria and two ventricles. Moreover, the veins are those that carry blood to the heart from the body organs. Those who get to the heart are two vena cava veins and four pulmonary veins. They reach the venae cavae to the right atrium and pulmonary, left atrium. Veins carry blood to the heart and continually open freely on their walls. Nevertheless, the arteries are the vessels that carry blood from the heart to the organs. From the heart the pulmonary artery and the aorta large, one or the right ventricle and the other, the left ventricule. Unlike veins, these arteries do not work freely, since the administration of blood to them is governed by the sigmoid valves, leaving ot only when blood pressure is exerted when the ventricles contract.

Finally, the circulatory process is a closed loop that starts and ends in the heart. The right cavities are what drive the blood containing wastes the body to the lungs for disposal. In the lungs oxygen taken up by the respiratory and oxygenated blood enters the heart through the left atrium, being driven intro the body form the left ventricle it is collected. Thus the blood with waste reaches the right atrium through the vena cava, while oxygenated blood reaches the heart through the pulmonary veins and is distributed throughout the body from the aorta. Entire circulatory process is divided into two parts which are called: greater or general circulation, the circulation of oxygenated blood throughout the body and the return of venous blood throughout the body to the heart, and smaller circulation or pulmonary, the venous circulation which sends blood to the lungs and oxygen collecting these, into the heart oxygenated blood.

These two videos have an explanation for you about how our Circulatory systems works in the body,
https://www.youtube.com/watch?v=_qmNCJxpsr0 and https://www.youtube.com/watch?v=_lgd03h3te8

This image is in Spanish but I like because show to you each part of the circulatory system.

1. Arteries of the head
2. Pulmonary artery system
3. Venous system of the larger circle
4. Arteries and veins of the lower limb
5. The heart
6. Aorta and large arteries
7. Capillary circulation
8. Arteries and veins of the upper limb