Answer:
Digestive
Explanation:
The by-products of digestion are solid waste which is removed through egestion.
It's a way of protecting the trees, and making sure they survive the winter and beyond. Leaves die during the winter months. If those dead leaves stayed on the trees, and new ones wouldn't grow in their place, the tree would have no way of making food for themselves.
Hope it helps. ☺
The phylum Echinodermata , which contains about 6000 species, gets its name from the Greek, literally meaning "spiny skin." Many echinoderms actually do have "spiny" skin, but others do not. This phylum exists exclusively in the sea, and cannot be found on land or in fresh water.