How to Tell Crystal From Glass. Here are some quick tips on how to distinguish classic crystal from plain glass. 1  Hold up a glass to the light. 2  If the glass acts as a prism and you see a rainbow you are holding crystal. 3  If not, it is just plain glass. 4  When struck, crystal produces a musical ring.
Blood pressure is controlled by tiny muscles that line the inside of your blood vessels. These muscles allow your arteries to operate like soft rubber tubes, that expand with each beat of your heart. When these muscles throughout the vascular system [the arteries and veins that carry blood] expand, blood pressure drops.
Answers from Contributors (1) SUCCESS! A. There really is no one organ that controls blood pressure. Blood pressure is controlled through how much blood goes through your heart and a delicate body balance achieved through the Cardiovascular, Central Nervous, and Urinary Systems. Neurotransmitters in the brain signal the heart to beat quicker and increase blood pressure when it becomes too low.