Biology

3. Bodies consist of repeated segments.
6. Gastrula's first indentation form in the mouth.
9. Sessile form of cnidarin.
10. Most diverse arthropods
11. Spiny-skinned marine animals.
12. Study of relationship amongst organisms and the enviroment.
13. Unique stage in embryonic development of animals.
15. Population growth that is proportional to the size of the population.
19. Factors that limit large population.
20. Immediate ancestor of animals.
21. Aquatic, sessile animals that are either asymmetrical or radially symmetrical.
22. vascular system Enables echinoderms to move, sense their environment, acquire food, exchange gases, and get rid of metabolic wastes.

1. Unsegmented animals that lack a coelom.
2. Free swimming form of cnidarin.
4. Segmented animals with jointed appendages and a chitin-rich exoskeleton.
5. Unsegmented worms that molt periodically.
7. Improves flexibility and increases the potential for specialized body parts.
8. Factors that limit population regardless of size.
14. Helps determine the population size.
16. density Measure of the number of individuals per unit area of habitat.
17. Population growth that stabilize indefinitely at the habitat' carrying capacity.
18. The three groups of primates are prosimians, monkeys, and ___.