Overview of Circulatory Systems

The blood circulatory system is a closed loop that distributes oxygenated blood to the body and returns deoxygenated blood to the heart.

Arteries carry oxygenated blood away from the heart, while veins return deoxygenated blood to the heart.

Capillaries are tiny vessels located between arteries and veins, where gas exchange takes place.

Systemic circulation carries oxygenated blood from the left ventricle of the heart to the body tissues and returns deoxygenated blood to the right atrium.

The aorta is the main artery of the systemic circulation, carrying oxygenated blood from the left ventricle to all parts of the body.

The superior vena cava collects deoxygenated blood from the upper body and returns it to the right atrium.

The inferior vena cava collects deoxygenated blood from the lower body and returns it to the right atrium.

The pulse is the rhythmic expansion and contraction of an artery that can be felt, and it corresponds to the heartbeat.

The lymphatic system is a vital network of vessels, fluid, and tissues responsible for defending the body against infections and removing excess interstitial fluid.

Interstitial fluid is the fluid that surrounds cells in tissues, providing nutrients and removing waste products. It's essentially the liquid portion of blood that leaks out of capillaries into the surrounding tissues.

Capillary exchange refers to the movement of fluid, nutrients, and waste products between capillaries and the surrounding interstitial space. It's a crucial process for delivering oxygen and nutrients and removing waste products from cells.

Capillary blood pressure (CBP) forces fluid out of capillaries into the surrounding tissue, carrying nutrients and other molecules. It's like pushing a substance out of a container with pressure.

Blood colloid osmotic pressure (BCOP) is the pressure that pulls fluid back into capillaries, drawing in waste products and other molecules. This pressure is mainly due to the presence of proteins in the blood.

Normally, approximately 85% of the fluid that leaves capillaries is reabsorbed back into the bloodstream. The remaining 15% is collected by the lymphatic system.

Lymphatic capillaries are tiny, blind-ended vessels that collect the excess interstitial fluid that wasn't reabsorbed during capillary exchange. They're like tiny pipes picking up the leftover liquid.

Edema is the swelling caused by the buildup of excess interstitial fluid in tissues. It occurs when the lymphatic system can't properly drain the excess fluid.