Explain why an artery may be described as an organ.

Tissues are defined as being a collection of different types of cell.Similarly, organs are defined are being a collection of tissues, which are joined in a structural unit to serve a common function.An artery is made up of several types of tissues including: Elastic tissue - this evens out the pressure changes in the vessel when the heart ventricles contract, by stretching and recoiling.Smooth muscle - for vasoconstrictionEndothelium lining - this is smooth to reduce friction. The common function that the tissues of the artery share is to transport blood away from the heart.