lucidmor.blogg.se - Blood on a wall

The heart as already well known is the pump of the system that sends out blood in arteries as arteries carry blood away from the heart.

Capillaries- smaller blood vessels that link arteries and veins together.

Arteries – carry blood away from the heart at high pressure.

There are five main types of blood vessels in a closed circulatory system:

Mammals blood loses its pressure as it passes through the lungs therefore, returns back to the heart to become boosted again to ensure the blood is able to reach the rest of the body. Organisms that are active have evolved a closed circulatory system in which blood is kept within the vessels all the way through the circuit. The vessels allow blood to be pumped at a high pressure to deliver nutrients and remove metabolic waste effectively.

The basic overall structure for veins and arteries is including the tunica intima, they have an additional two tunics tunica media (middle layer) is the region where the blood vessels consist of smooth muscle and elastin fibres and the tunica adventitia (outer layer) is mainly composed of collagen fibres.īlood vessels are tubes that run through the transport system in which blood is transported.

The endothelium is known as the tunica intima.

Capillaries are blood vessels that are one cell thick (endothelium) where the main diffusion and exchange takes place.

Veins are blood vessels that return blood back to the heart where venules are smaller versions of veins.

Exchange of nutrients, waste and oxygen occur at the capillaries within tissues at cellular level.

Arterioles are smaller arteries that diverge into capillary beds.

The main artery in the heart is the aorta and arteries carry blood away from the heart.