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Nov 3, 2023 · The heart is a muscular organ that pumps blood around the body by circulating it through the circulatory/vascular system. It is found in the middle mediastinum, wrapped in a two-layered serous sac called the pericardium.
- Surface Projections of The Heart
Borders of the heart. The heart is placed within the middle...
- Innervation of The Heart
The innervation of the heart refers to the network of nerves...
- Diagrams, Quizzes and Worksheets of The Heart
Using our unlabeled heart diagrams, you can challenge...
- Coronary Arteries
Coronary arteries and cardiac veins. The heart is a...
- Ductus Arteriosus
Ligamentum arteriosum (also known as Ligament of Botallo or...
- Atria
Basic anatomy of the heart. The heart is at the center of...
- Ventricles
The heart is made up of four muscular chambers that work...
- Heart Valves
Understanding heart valves anatomy is important in grasping...
- Surface Projections of The Heart
- Pericardium
- Structure of The Heart Wall
- Chambers of The Heart
- Valves of The Heart
- Conduction System of The Heart
The heart sits within a fluid-filled cavity called the pericardial cavity. The walls and lining of the pericardial cavity are a special membrane known as the pericardium. Pericardium is a type of serous membrane that produces serous fluid to lubricate the heart and prevent friction between the ever beating heart and its surrounding organs. Besides ...
The heart wall is made of 3 layers: epicardium, myocardium and endocardium. 1. Epicardium. The epicardium is the outermost layer of the heart wall and is just another name for the visceral layer of the pericardium. Thus, the epicardium is a thin layer of serous membrane that helps to lubricate and protect the outside of the heart. Below the epicard...
The heart contains 4 chambers: the right atrium, left atrium, right ventricle, and left ventricle. The atria are smaller than the ventricles and have thinner, less muscular walls than the ventricles. The atria act as receiving chambers for blood, so they are connected to the veins that carry blood to the heart. The ventricles are the larger, strong...
The heart functions by pumping blood both to the lungs and to the systems of the body. To prevent blood from flowing backwards or "regurgitating" back into the heart, a system of one-way valves are present in the heart. The heart valves can be broken down into two types: atrioventricular and semilunar valves. 1. Atrioventricular valves. The atriove...
The heart is able to both set its own rhythm and to conduct the signals necessary to maintain and coordinate this rhythm throughout its structures. About 1% of the cardiac muscle cells in the heart are responsible for forming the conduction system that sets the pace for the rest of the cardiac muscle cells. The conduction system starts with the pac...
Oct 20, 2024 · The endocardium lines the chambers where the blood circulates and covers the heart valves. It is made of simple squamous epithelium called endothelium, which is continuous with the endothelial lining of the blood vessels (Figure \(\PageIndex{4}\)).
Oct 31, 2024 · What is the heart wall made up of? 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 Editors of Encyclopaedia Britannica
- In humans, the heart is situated between the two lungs and slightly to the left of center, behind the breastbone. It rests on the diaphragm, the mu...
- The pumping of the heart, or the heartbeat, is caused by alternating contractions and relaxations of the myocardium. These contractions are stimula...
- The rhythmic noises accompanying the heartbeat are called heart sounds. The two distinct sounds are heard, a low, slightly prolonged “lub” (first s...
- The Heart Wall Is Composed of Three Layers. The muscular wall of the heart has three layers. The outermost layer is the epicardium (or visceral pericardium).
- The Atria Are the Heart’s Entryways for Blood. The left atrium and right atrium are the two upper chambers of the heart. The left atrium receives oxygenated blood from the lungs.
- Each Heart Beat Is a Squeeze of Two Chambers Called Ventricles. The ventricles are the two lower chambers of the heart. Blood empties into each ventricle from the atrium above, and then shoots out to where it needs to go.
- The Valves Are Like Doors to the Chambers of the Heart. Four valves regulate and support the flow of blood through and out of the heart. The blood can only flow one way—like a car that must always be kept in drive.
The human heart consists of four chambers: The left side and the right side each have one atrium and one ventricle. Each of the upper chambers, the right atrium (plural = atria) and the left atrium, act as receiving chambers and the combination of gravity and atrial contraction move blood into the lower chambers, the right ventricle and the ...
The heart has the shape of a pyramid, with its apex pointing towards the left nipple while its base forms the posterior surface of the heart. Other surfaces are the anterior, inferior (or diaphragmatic), and two pulmonary surfaces facing the lungs.
