Circulatory system

 

Your heart and blood vessels make up the circulatory system. The main function of the circulatory system is to provide oxygen, nutrients and hormones to muscles, tissues and organs throughout your body. Your heart pumps blood to the body through a network of arteries and veins (blood vessels). Your circulatory system can also be defined as your cardiovascular system. Cardio means heart and vascular refers to blood vessels. The circulatory system provides blood to all the body’s tissues so they can function.

What does the circulatory system do?

The circulatory system’s function is to move blood throughout the body. This blood circulation keeps organs, muscles and tissues healthy and working to keep you alive. The circulatory system also helps your body get rid of waste products. This waste includes:

·         Carbon dioxide from respiration (breathing).

·         Other chemical byproducts from your organs.

·         Waste from things you eat and drink.

How does the circulatory system work?

Your circulatory system function with the help of blood vessels that include arteries, veins and capillaries. These blood vessels work with your heart and lungs to continuously circulate blood through your body.

·         The hearts’ bottom right pumping chamber (right ventricle) sends blood that’s low in oxygen (oxygen-poor blood) to the lungs. Blood travels through the pulmonary trunk (the main pulmonary artery).

·         Blood cells pick up oxygen in the lungs.

·         Pulmonary veins carry the oxygenated blood from the lungs to the heart’s left atrium (upper heart chamber).

·         Your lungs get rid of the carbon dioxide when you exhale.

What are the parts of circulatory system?

The parts of your circulatory system are:

Heart: A muscular organ that pumps blood throughout your body.

Blood vessels: Which includes your arteries, veins and capillaries.

Blood: Made up of red and white blood cells, plasma and platelets. 

How circulatory system circulate blood?

Your circulatory system has three circuits. Blood circulates through your heart and through these circuits in continuous pattern. 

The pulmonary circuit

This circuit carries blood without oxygen from the heart to the lungs. The pulmonary veins returns oxygenated blood to heart.

Arteries

Arteries are thin, muscular tubes that carry oxygenated blood away from the heart and to every part of your body. The aorki is the body’s largest artery. It starts at the heart and travels up the chest (ascending aorta) and then down into the stomach. The coronary arteries branch off the aorta which then branch into smaller arteries.

Veins

These blood vessels return oxygenated blood to the heart. Veins at start small (venules) and get larger as they approach your heart. Two central veins deliver blood to your heart, the superior vena cava carries blood from the upper body (head and arms) to the heart. The inferior vena cava brings blood from the body (stomach, pelvis and legs) to the heart.

Capillaries

These blood vessels connect very small arteries (arterioles) and veins (venules). Capillaries have thin walls that allow oxygen, carbon dioxide, nutrients and waste products to pass into and out of the cells.