The Human Heart
The human heart, a marvel of the human body, is a muscular organ that pumps blood throughout the body via the circulatory system?. It supplies oxygen and nutrients to the body while removing metabolic waste such as carbon dioxide?.
Location and Structure
The heart is located in the middle of the chest, between the lungs, and slightly to the left of the sternum?. It rests on the diaphragm, the muscular partition between the chest and the abdominal cavity?. The heart is about the size of a closed fist? and weighs between 230 and 340 grams?.
The heart consists of several layers of a tough muscular wall, the myocardium. A thin layer of tissue, the pericardium, covers the outside, and another layer, the endocardium, lines the inside?. The heart cavity is divided down the middle into a right and a left heart, which in turn are subdivided into two chambers. The upper chamber is called an atrium, and the lower chamber is called a ventricle?.
Functioning
The heart beats constantly, about 100,000 times a day, and three billion times over an average lifetime?. The heart pumps about 2,000 gallons of blood every day. An electrical system, the cardiac conduction system, controls the rhythm of your heart.
In humans, deoxygenated blood enters the heart through the right atrium from the superior and inferior venae cavae and passes to the right ventricle. From here, it is pumped into pulmonary circulation to the lungs, where it receives oxygen and gives off carbon dioxide?. Oxygenated blood then returns to the left atrium, passes through the left ventricle and is pumped out through the aorta into systemic circulation?.
Cartoon Depiction of the Heart
Cartoon depictions of the human heart often simplify the complex structure of the heart for easier understanding. They typically show the heart as a red or pink organ with a shape similar to the traditional heart symbol. These depictions highlight the four chambers of the heart and the major blood vessels, such as the aorta and the pulmonary artery. They may also include representations of the flow of blood through the heart to illustrate its function. These cartoon images are widely used in educational materials for children and adults alike to help
