Fill in all the gaps, then press "Check" to check your answers. Use the "Hint" button to get a free letter if an answer is giving you trouble. You can also click on the "[?]" button if available to get a clue. Note that you will lose points if you ask for hints or clues!
arteries blood vessels body capillaries circulatory system digested food gaps glucose lungs oxygen pumps small small intestine surface area thin walls veins vessels water