San Bernardino County Sheriff's Department Infographic Thursday, November 16, 2017 The San Bernardino County Sheriffâs Department is the law enforcement agency for the largest geographical county in the nation. The department serves over 2.1 million residents with 15 patrol stations and 3800 employees to ensure the quality and safety of those we serve...
Veins branch at their beginnings into tiny venules which join capillaries.  Veins have valves which stop the blood from flowing backward. Compared to the arteries, pressure in the veins is very low. The blood is being pushed through the arteries as the heart squeezes the blood out. This is not true for the veins. Blood is pushed through the veins when body muscles contract and squeeze the veins.
Best Answer: Blood pressure elevates when the arterioles constrict, which increases the volume carried in the larger arteries, which increases the pressure exerted against the interior walls of those arteries.When vessels constrict, they tighten, and reduce the amount of space inside.ee constrict think choke. Constricting arteries mean the diameter of the hollow part of the arteries where the blood flows is getting smaller. This generally increase blood pressure. When the blood vessel dilates, the diameter increases, lowering blood pressure.