You have 100,000 feet of blood vessels in your body. The tinest ones must be close to the cells. Each cell needs a constant supply of oxygen and glucose and other nutrients and must have means to remove wastes that they make.
capillaries
capillaries
because they are hormone-secreting and so they have to be in close contact with blood vessels
There are blood capillaries close to all of the cells in our body, so that the cells can get all of the energy they need to survive.Blood capillaries are only one cell thick, so that nutrients and oxygen can pass through them easily.
All the body cells can stay close to the capillaries for the exchange for materials with the blood
Capillaries are one-cell wide blood vessels. They allow intimate close-contact with muscle and other body cells with red blood cells. It is in capillaries that oxygen exchange occurs. In close contact with muscular myoglobin, adult hemoglobin releases its oxygen and myoglobin picks it up.
one of them is the capillaries
Closed circulatory systems have blood that does not flow in defined blood vessels. Examples are insects and how their organs are bathed continually in "blood". Open circulatory systems have blood that flows in vessels. Humans have this system as blood flows in veins, arteries and capillaries.
Closed circulatory systems have blood that does not flow in defined blood vessels. Examples are insects and how their organs are bathed continually in "blood". Open circulatory systems have blood that flows in vessels. Humans have this system as blood flows in veins, arteries and capillaries.
If we didn't have capillaries, we would die. This is because CAPILLARIES are the passageways between the arteries (carrying oxygen- rich blood AWAY from the heart) and the Veins (carrying oxygen- poor blood back INto the heart). Capillaries come in close contact with the body's organs. They exchange their oxygen- rich blood (provided by the arteries) with the organ's oxygen- poor blood (containing carbon dioxide). Thus, the body's organ supply of oxygen- rich blood is replenished. Then, the capillaries give their oxygen- poor blood (from the organs) to the Veins, which bring the blood back to the heart, so it can be filled with oxygen again. It's all a big cycle, and our capillaries play a big role in this cycle. The heart, blood, and blood vessels (arteries, veins, and CAPILLARIES) are all a part of the amazing Cardiovascular System! (Also known as Circulatory system) We really need those Capillaries !! So... What would happen, you ask? Well, the blood in the arteries an the blood in the veins would mix. That is very bad. Our body could not survive if oxygen-rich blood and oxygen- poor blood mixed. We have the capillaries to ensure they never interact!!
Capillaries. Since they are only once endothelial cell thick, they can exchange gas, nutrients, and waste across their membrane. Capillaries in the brain have endothelial cells close together to onyl allow a slecetive exchange of materials, while capillaries in the kidney or liver have gaps between the endothelial cells to allow the exchange of a lot of materials.
They have capillaries close to their surfaces.