In fact, the world of leaves is so varied, even downright weird sometimes, that
it can actually be hard to figure out where a plant's leaves are. If you look at a maple tree's branch, it's easy to recognize that the leaf is the flat, green thing attached to the branch with a slender little stem-like item -- the leaf is the thing that turns colorful in the fall, and falls off. No problem there. On the other hand, are you sure where the actual leaves are on the tomato sprig? Is what you see one or more leaves, or a division of just one leaf, or what?

Here are some hints that sometimes can help you decide whether the thing you're seeing is a leaf: Identifying what's a leaf -