1. The process whereby the DNA sequence for a gene is copied into mRNA; occurs in the nucleus.

2. Breakdown of food substances into simpler forms that can be absorbed and used

3. A biological species name consisting of two terms: the genus name and the species name. Usually written in Latin.

4. A test that determines if an organism is homozygous dominant or heterozygous; an organism of unknown genotype but dominant phenotype is crossed with a homozygous recessive organism. If any of the offspring show the recessive phenotype, then the genotype of the parent being tested is heterozygous for that trait. (Examples of expected outcomes: TT X tt = Tt; Tt X tt = 1/2 Tt and 1/2 tt.)

5. Old kingdom classification for all bacteria, used prior to the establishment of domains bacteria and archaea.

6. chemical substance that an organism requires to live

7. A cellular organelle involved in the digestion of nutrients and the destruction of foreign particles. Numerous in leukocytes (white blood cells), which fight infection.

8. An inborn pattern of behavior involving complex responses to a stimulus.

9. the passing of genetic traits from parent to offspring

10. An organized way to test scientific hypotheses

11. The first level of protein structure, which consists of amino acids linked in linear sequence like beads on a necklace.

12. The stage of development after the fertilized cell implants into the uterus but before its cells take on a recognizable shape.

13. Observation using measuring tools and is given in a number form (example: 5 milliliters of liquid)

14. Considered to be ancient life forms that evolved separately from bacteria and blue-green algae. Live in the most extreme environments of all Earth's life forms.

15. The final stage in speciation; populations of organisms become separated and can no longer interbreed; they are either unable to mate or unable to produce viable offspring.

16. An organism's maintenance of a constant (unchanging) internal environment; metabolic equilibrium actively maintained by several complex biological processes that operate via the nervous system to offset disrupting changes in temperature, blood sugar, etc.

17. The motion of charged particles in a gel under the influence of an electric field; frequently used to separate segments of DNA.

18. A system formed by the interaction of a community of organisms with their physical environment; a small part of a biome; matter and energy are transferred as organisms interact with their environment.

19. A symbiotic relationship between two different kinds of species in which one receives benefits from the other without damaging it; one species is helped and the other is unaffected.

20. The combined biotic (living) and abiotic (nonliving) factors that are found in the area where an organism lives.

21. The process by which ATP is formed using chemicals as an energy source instead of light; limited to certain bacteria and fungi

22. limiting factor that affects all populations in similar ways, regardless of population size

23. A primary category in biological taxonomy, especially of animals, that ranks above the class and below the kingdom.

24. A reasoned judgment: a judgment or decision reached by reasoning.

25. The wide, partially enclosed part of a river where it flows into the ocean; a nutrient-rich area where fresh and salt water mix.