Why are arteries muscular?

Answer 1

Arteries have to endure a much higher pressure, but the muscle wall surrounding the arteries are actually there to constrict and relax to help regulate blood pressure. Since blood pressure is one of your more important functions, the arteries are constantly constricting and relaxing to keep you BP at a reasonable level. They also play a role in blood shunting during your fight or flight response, but that tends to deal more with capillaries.

In short the smooth muslce lining your arteries have various functions, but the key functions to their existence are :

1.) Dealing with the higher pressure and not bursting by causing reinforcement to the pressure.

2.) To constrict and diulate in order to help regulate blood pressure.

There are other reasons for this but most fringe more on the molecular level or deal with secondary messengers, G proteins.

Answer 2

Blood flow from the heart is pulsatile and the fluctuations in pressure are not a desirable characteristic for a hydrological network. High pressure can burst a vessel while low pressure doesn't supply a constant amount of nutrients. Elasticity in the arteries helps dampen the pulses and keep the pressure more constant.

Answer 3

Because blood passes through them with a greater pressure compared to the veins; they have to withstand the pressure.

Answer 4

It has a thick, muscular wall for carrying blood at high pressure. An elastic wall gradually reduces the harsh surge of the pumped blood to a steadier flow.