They breathe through their skin. Air dissolves on the mucus of their skin, so they MUST stay moist to breathe.
If worms dry out, they suffocate. As fresh air is taken in through the skin, oxygen is drawn into the worm's circulatory system, and the worm's hearts pump the oxygenated blood to the head area.
Sun grows plants which feed animals or feeds the animals prey
All above I think I don't know
Answer:
The definition of trade off is an exchange where you give up one thing in order to get something else that you also desire. An example of a trade off is when you have to put up with a half hour commute in order to make more money.
Explanation:
The dorsal surface in for legged animals is called superior