The mammalian circulatory system
- The hepatic portal vein is the blood vessel that takes the products of the small intestine to the liver.
- The coronary artery takes blood to the heart.
- Renal- Kidneys
- Ateries, arterioles and veins all have the same basic layered structure. From the outside inwards, these are:
- tough outter layer, that resists pressure changes from both within and outside
- muscle layer that can contract and control the blood flow
- elastic layer that helps maintain blood pressure by stretching and recoiling
- thin inner endothelium that is smooth to restrict friection and thin to allow diffusion
- lumen is the central cavity of the vessel through which the blood flows.
- Thick muscle layer so the volume of blood can be controlled
- Thick elastic layer to keep a high blood pressure so it reaches all over the body.
- Overall thickness of the wall resists the vessel bursting undeer pressure
There are no valves because the blood is under constant high pressure and doesn't flow backwards
-Arterioles carry blood, under lower pressure than arteries, from arteries to capilaries and cotrol blood flow between the two.
-Muscle layer is relatively thicker than in arteries as the contraction of this muscle layer…