The cardiovascular system (sometimes called the circulatory system) is practically the most vital part of the human body, without it humanity would’ve been extinct millennia ago. This system consists of the heart, blood vessels, and the veins and arteries that run through the entire human body. Responsible for transporting the nutrients, oxygen, hormones, and the cellular waste products all throughout the body, the cardiovascular system is fueled by the body’s hardest-working organ -the heart. Even at rest, the average human heart easily pumps over five liters of blood throughout the human body every minute. The heart is located just behind and slightly left of the breastbone, where the organs connection to the cardiovascular system keeps the human body alive. It is also the main key organ in the cardiovascular system.
The human heart receives commands from the body through the circulatory system, that tells it when to pump more or less blood depending on an individual’s needs. While people are exercising or terrified, the heart pumps even faster to increase the delivery of oxygen due to heightened emotion or activity. There are four chambers that enclose the heart with thick muscular walls. The bottom part of the organ is divided into two chambers called the left and right ventricles, which pump blood out of the heart and throughout the entire body. The interventricular septum is wall that divides the ventricles. The upper part of the heart consists of the other two chambers, called the right and left atria, which receive blood upon entering the heart. The left and right atria are separated from the ventricles by the atrioventricular valves a wall called the interatrial septum divides. These divides are separated by the tricuspid valve, while the mitral valve separates the left atrium and the left ventricle. Another two cardiac valves separate the ventricles and the large blood vessels that carry blood exiting the heart. This is the pulmonic valve, which separates the right ventricle from the pulmonary artery leading up to the lungs, and the aortic valve, which then separates the left ventricle from the aorta which is the body’s largest blood vessel. Arteries transport blood away from the heart. These are known as the thickest blood vessels, with muscular walls that need to contract to keep the blood moving away from the heart and through the body.