Biology Chapter 3 Vocabulary - Classifying Animals

9. one of the bones or blocks of cartilage that make up a backbone.
10. a worm whose body is divided into sections, such as earthworms or leeches.
11. an invertebrate divided into three parts.
12. a gas-filled organ that allows a bony fish to move up and down in water.
14. an armlike body part in invertebrates that is used for capturing prey.
18. a structure used by some animals to breathe in water.
19. a member of the largest group of invertebrates, which includes insects.
20. a group of living things that includes separate species.
25. the process by which an arthropod sheds its external skeleton.
27. the name given to each species, consisting of its genus and its species label.
28. changes in form during development in which earlier stages do not look like the adult.
30. subdivision of a kingdom.
31. group things based on the features they share.
32. a stage in the development of some insects that leads to the adult stage.
33. an arrangement of body parts that resembles the arrangement of spokes on a wheel.

1. having a body temperature that changes with temperature of surroundings.
2. changes in form during development in which earlier stages look like the adult.
3. a simple worn that is flat and thin.
4. a small structure used by echinoderms for movement.
5. a major change in form that occurs as some animals develop into adults.
6. a body plan that consists of left and right halves that are the same.
7. an animal with a backbone.
8. having a body temperature that says the same.
13. a worm with a smooth round body and pointed ends.
15. a class of arthropods that include crabs, lobsters, crayfish, and sow bugs.
16. a soft material found in vertebrate skeletons.
17. a vertebrate that lives at first in water and them on land.
21. a group of organisms that can breed with each other to produce offspring like themselves.
22. an invertebrate animal that includes jellyfish, corals, and hydras.
23. an egg-laying vertebrate that breathes with lungs.
24. a class of arthropods that includes spiders, scorpions, mites, and ticks.
26. an animal that does not have a backbone.
29. a milk-producing structure on the chest or abdomen of a mammal.