To help you think about these very tiny vessels (capillaries) we could use another analogy. This time we will use the analogy of city water pipes. A large pipe brings water from the river to the city. This pipe divides off into smaller pipes until it gets to your neighborhood.

When the water system needs to get water to each house along the main pipe, how can it do this?

How would the used water from washing dishes, bathing, etc. get back out of the houses to the sewer treatment plant to be cleaned?

See if your group can come up with an idea and draw it on your whiteboard. Then make a quick draw of your group idea below so you can refer to it later. Be ready to share your ideas with the rest of the class.