Capillaries are the smallest of blood vessels
Capillaries are the smallest of blood vessels. They serve to distribute oxygenated blood from arteries to the tissues of the body and to feed deoxygenated blood from the tissues back into the veins. The capillaries are thus a central component in the circulatory system, essentially between the arteries and the veins. When pink areas of skin are compressed, this causes blanching because blood is pressed out of the capillaries. The blood is the fluid in the body that contains, among other elements, the red blood cells (erythrocytes) that carry the oxygen and give the blood its red color
Capillaries do not have the muscular/elastic tissue of other blood vessels. They have a single celled wall to help substances be transported through organisms.
Arteries carry blood away from the heart; the main artery is the aorta. ... Capillaries carry blood away from the body and exchange nutrients, waste, and oxygen with tissues at the cellular level. Veins are blood vessels that bring blood back to the heart and drain blood from organs and limbs.
Capillaries are small, normally around 3-4µm, but some capillaries can be 30-40 µm in diameter. The largest capillaries are found in the liver. ... Capillaries connect arterioles to venules. They're similar to arteries but not as strong or as thick. Unlike arteries, veins contain valves that ensure blood flows in only one direction. (Arteries don't require valves because pressure from the heart is so strong that blood is only able to flow in one direction.
Circulation is the transport mechanism that involves the whole body, from the largest vessels to the smallest. The capillary level is where it is crucial to maintain the exchange of nutrients and oxygen and the removal of metabolic waste products such as carbon dioxide, which accumulates because of normal cellular function. There is a huge network of extremely small blood vessels in our body, some of which are four times thinner than a strand of hair. These networks of small vessels surround all organs and tissues in the body and are vital to cellular function.
There are three main types of capillaries: continuous, fenestrated, and sinusoidal.