You will need:
- A volunteer (with visible veins)
- Your own hand
Have fun playing with your veins while you
learn something new about your anatomy.
INSTRUCTIONS
- Ask an adult to help you get this experiment right.
- Place your index and middle finger on the vein of your volunteer’s hand.
- Pressing down on it, move only your index finger outwards while the middle finger stays where it is.
- Gently release the index finger while the middle finger is still on the vein.
- Observe how fast the blood refills into the vein.
- Repeat the entire process again but this time move the middle finger outwards and keeping the index finger constant release the middle finger.
- How fast does the vein refill this time?
RESULT
The vein would have refilled faster the second time around when you lift your middle finger. In fact, the blood would not have refilled the first time until you lifted your middle finger as well. The reason for this is that our blood is circulated first through the arteries, when it is pumped out by the heart and travels throughout the body through the arteries. However, the veins carry the blood back from different parts of the body. This experiment was only realized in the 17th century by William Harvey.
