Mystery #4Tier 2body / digestion

Why do you need to poo?

Once your body has taken the goodness out of your food, there's always something left over that has to leave. Why can't your body use all of a meal, and what is the leftover part really made of?

A spread of high-fibre foods, vegetables, fruit, wholegrains, nuts and seeds, the kind of food that keeps digestion healthy. — Photo: Keith Weller, USDA ARS · Public domain · via Wikimedia Commons

Your guess

What's your hunch about why your body needs to get rid of leftovers, and what happens to them in the last part of your gut?

There's no single magic word to type, have a go in your own words, then reveal the answer to see how close you got.

Make a guess to unlock the hints and the answer.