Grandparents have always been important. Today, they're even more important. In busy, two-career and single-parent families, an involved grandparent goes a long way to filling a void for children. In extreme situations, the courts have found it's often a grandparent who can reach a troubled teen when no one else can.
Here's how to enlarge your veins and arteries for plasma donation: 1  Heat up your arm. When veins become overheated, they expand, and draw closer to the skin. 2  Hold off on drinking and smoking. Both smoking and drinking alcoholic beverages makes veins and arteries smaller and harder. 3  Hold off on the caffeine.
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.