Arteries carry oxygen-rich blood away from your heart, and veins carry oxygen-poor blood back to your heart. The one-way vascular system carries blood to all parts of your body. This process of blood flow within your body is called circulation. Arteries carry oxygen-rich blood away from your heart, and veins carry oxygen-poor blood back to […]
The one-way vascular system carries blood to all parts of your body. This process of blood flow within your body is called circulation. Arteries carry oxygen-rich blood away from your heart, and veins carry oxygen-poor blood back to your heart. In pulmonary circulation, though, the roles are switched. It is the pulmonary artery that brings […]
Blood is carried from your heart to the rest of your body through a complex network of arteries, arterioles, and capillaries. Blood is returned to your heart through venules and veins. The one-way vascular system carries blood to all parts of your body. This process of blood flow within your body is called circulation. Arteries […]
The one-way vascular system carries blood to all parts of your body. This process of blood flow within your body is called circulation. Arteries carry oxygen-rich blood away from your heart, and veins carry oxygen-poor blood back to your heart. In pulmonary circulation, though, the roles are switched. It is the pulmonary artery that brings […]
A heartbeat is a two-part pumping action that takes about a second A heartbeat is a two-part pumping action that takes about a second. As blood collects in the upper chambers (the right and left atria), the heart’s natural pacemaker (the SA node) sends out an electrical signal that causes the atria to contract. This […]
Your heart is located between your lungs in the middle of your chest, behind and slightly to the left of your breastbone (sternum). A double-layered membrane called the pericardium surrounds your heart like a sac. The outer layer of the pericardium surrounds the roots of your heart’s major blood vessels and is attached by ligaments […]
Your heart is located between your lungs in the middle of your chest, behind and slightly to the left of your breastbone (sternum). A double-layered membrane called the pericardium surrounds your heart like a sac. The outer layer of the pericardium surrounds the roots of your heart’s major blood vessels and is attached by ligaments […]
The fetus does not use its own lungs until birth, so its circulatory system is different from that of a newborn baby. The baby growing inside of the mother’s uterus (the womb) is called a fetus. The growing fetus is fully dependent on a special organ called the placenta for nourishment. One side of the […]
Coronary Circulation The heart muscle, like every other organ or tissue in your body, needs oxygen-rich blood to survive. Blood is supplied to the heart by its own vascular system, called coronary circulation. The aorta (the main blood supplier to the body) branches off into two main coronary blood vessels (also called arteries). These coronary […]
Electrical impulses from your heart muscle (the myocardium) cause your heart to beat (contract). This electrical signal begins in the sinoatrial (SA) node, located at the top of the right atrium. The SA node is sometimes called the heart’s “natural pacemaker.” When an electrical impulse is released from this natural pacemaker, it causes the atria […]