Try it on paper first. A hint, the key idea and the worked solution are here when you need them.
Use this key to four pond animals. If the animal has a hard shell, it is a snail. If not, and it has no legs, it is a leech. If it has eight legs, it is a water spider. If it has six legs, it is a water beetle. What is animal B, with no shell and eight legs? What is animal D, with no shell and no legs? What is the largest number of questions that the key asks?
Taxonomical aids help to identify organisms.
Have you tried it?
Work it out on paper first. It is fine to get stuck or make a mistake: that is how we learn. When you are ready, go through the solution one step at a time, and check each step against your own.
Step 1. Animal B. No shell, it has legs, eight of them: a water spider.
Step 2. Animal D. No shell and no legs: a leech.
Step 3. Most questions. For the spider or the beetle, the key asks about the shell, the legs and the number of legs: questions.
Answer: B is a water spider, D is a leech, and at most questions are asked.
Log in to join the discussion.
Loading…