The heart, arteries, veins, and blood functioning as a unit.
A system of arteries and veins, together with the heart, which makes the blood circulate around the body.
The means of transportation of fluids within the body (e.g.. blood is transported by the veins, arteries, and heart).
Network of channels through which a fluid passes around the body, especially, the network of arteries and veins transporting blood in the body. Also includes the thin-walled capillaries of the lymphatic system.
A system concerned with circulation of body fluids. It includes the cardiovascular and lymphatic systems.
Also known as the cardiovascular system or vascular system; controls the steady circulation of the blood through the body by means of the heart and blood vessels.
The system that contains the heart and the blood vessels and moves blood throughout the body. This system helps tissues get enough oxygen and nutrients, and it helps them get rid of waste products.
Body system consisting oft he heart and blood vessels, which transport blood around the body.
The heart and blood vessels collectively form the circulatory system, also referred to as the cardiovascular system. This intricate network is responsible for facilitating the continuous circulation of blood throughout the body. Its vital functions include supplying oxygen and essential nutrients to the body’s tissues while simultaneously removing carbon dioxide and other waste products.
The intricate network responsible for transporting blood throughout the body consists of two primary components: systemic circulation and pulmonary circulation. Systemic circulation encompasses the entire body, delivering blood to every part except the lungs. On the other hand, pulmonary circulation specifically caters to the lungs, ensuring that the blood receives a fresh supply of life-sustaining oxygen.
Oxygen-enriched blood originating from the pulmonary circulation undergoes a crucial transition as it enters the systemic circulation, propelled by the forceful contractions of the left ventricle within the heart. The left ventricle expels the blood with significant pressure, propelling it into the aorta, the body’s primary artery. From the aorta, the blood embarks on a journey through a network of arteries, gradually transitioning into smaller arterioles that reach every nook and cranny of the body. As the arterioles penetrate the body’s tissues, they give rise to intricate networks of delicate blood vessels called capillaries. It is within these capillaries that a remarkable exchange takes place: oxygen and vital nutrients effortlessly traverse the thin capillary walls, diffusing into the surrounding tissues, while carbon dioxide and other metabolic byproducts make their way back into the capillaries, preparing for their eventual removal. The deoxygenated blood, having completed its mission, finds its way back to the heart through a series of venules (small veins), veins, and the mighty venae cavae, the two principal veins that play a pivotal role in the circulatory system.
Within the expansive network of the systemic circulation, an additional pathway known as the portal circulation plays a vital role in the transportation of nutrient-rich blood originating from the stomach, intestines, and other digestive organs. This specialized route utilizes the portal vein to deliver the blood directly to the liver. Upon arrival, the liver’s remarkable cells take charge, performing various tasks such as processing, storing, breaking down, or even reintroducing nutrients and other substances back into the broader circulation. Subsequently, the blood exits the liver through the hepatic vein, seamlessly merging with the primary systemic circulation through the inferior vena cava, the major vein responsible for returning blood to the heart from the lower parts of the body.
The deoxygenated blood, having completed its journey through the systemic circulation, finds its way back to the heart, specifically the right atrium. This crucial entry point marks the beginning of the blood’s transition into the pulmonary circulation. Propelled by the forceful contractions of the right ventricle, the blood embarks on a new phase of its voyage, coursing through the pulmonary artery towards the lungs. Within the lungs, a remarkable exchange occurs as carbon dioxide, a waste product, is relinquished in favor of life-giving oxygen. The rejuvenated blood, now saturated with oxygen, retraces its steps, making its way back to the heart through the pulmonary veins. Once inside the heart, it eagerly reintegrates with the systemic circulation, ready to nourish and sustain the body’s various tissues and organs.
During its intricate voyage from the heart to nourish the body’s tissues, blood experiences distinct pressure differentials depending on its location within the circulatory system. As the heart propels blood into the arteries, it does so with force, generating high pressure to ensure efficient distribution. In stark contrast, when blood returns to the heart through the veins, it does so at a considerably lower pressure. However, this doesn’t impede its journey thanks to the collaborative efforts of various mechanisms. Muscles in the limbs play a vital role by actively compressing the veins, effectively squeezing and propelling blood forward. Additionally, the veins themselves possess an ingenious system of valves that prevent backward flow, ensuring that the blood moves in the desired direction, further facilitating its return to the heart.