Biology Crossword

5. The dry mass of organisms.
7. An organism producing its own food from simple inorganic materials, e.g. by photosynthesis.
9. level The role an organism has in an ecosystem, including where it lives and what it eats.
11. The position an organism occupies in a food chain.
12. competition Individuals of the same species attempt to make use of the same scarce resources.
15. The place within an ecosystem where a population lives.
16. The process whereby cells release energy from organic molecules.
18. An organism obtaining food by feeding on complex organic matter, i.e. a consumer.
20. The name given to each stage in a succession.
21. factors Biological features of the environment that have an effect on a population of organisms.
23. The community of living organisms and the biotic factors that affect them.

1. chain A linked series of living organisms, each of which is the food for the next level, showing energy flow through the ecosystem.
2. Green plants and some bacteria that make their own food.
3. The changes that occur in an ecosystem over time.
4. All the populations that live in a particular place at the same time.
6. factors Physical and chemical features of the environment that have an effect on the population of organisms.
8. All the organisms of the same species living together in a particular habitat.
10. community The end stage in a succession.
13. A plant species found in the early stage of succession.
14. competition Individuals of more than one species attempt to make use of the same scarce resources
17. Heterotrophs, which obtain nourishment by feeding on other organisms.
19. productivity The total energy fixed during photosynthesis.
22. productivity The energy available for the next trophic level after respiration.