2. autosome Any chromosome that is not a sex chromosome

3. Homologous chromosomes Two chromosomes that have the same sequence of genes, the same structure, and pair during meiosis

4. Binary fission Form of asexual reproduction in single celled organisms

5. Radial symmetry Body plan in which the parts of an animal’s body are organized in a circle around a central axis

6. gamete Sex cell

7. Crossing-over Exchange of genetic material between homologous chromosomes during meiosis

8. oogenesis Production of an egg or ovum

9. Polar body Short lived product of the formation of gametes in oogenesis

10. Incomplete dominance Trait is intermediate between the two parents (ex. red and white makes pink)

11. codominance Both alleles for a gene are fully expressed (ex. A blood and B blood make AB blood)

12. Nitrogenous base A purine or a pyrimidine; makes up nucleotides

13. purine Adenine and guanine; nitrogenous base that has a double ring

14. pyrimidine Thymine, cytosine, or uracil; nitrogenous base with a single ring

15. codon 3 nucleotide sequence that codes an amino acid or signifies a start or stop signal (ex. AUG)

16. 6 kingdoms of living things Eubacteria Archaebacteria Protista Fungi Plantae Animalia

17. monocot Plant that produces seeds that have only one cotyledon

18. Nonvascular plants 3 groups of plants that lack true roots, stems, and leaves (ex. Liverworts, hornworts, mosses)

19. gymnosperms Woody, vascular seed plant whose seeds are not enclosed by an ovary or fruit

20. dicot An angiosperm that has two cotyledons and flower parts in groups of 4 or 5

21. cotyledon Embryonic leaf of a seed

22. Level of organization in Living Things Cells  tissues  organs  organ systems  organisms

23. abiotic Environmental factor that is not associated with the activities of living organisms

24. biotic Environmental factor that is associated with the activities of living organisms

25. RNA polymerase Enzyme that starts the formation of RNA by using a strand of DNA as a template

26. promoter Nucleotide sequence on DNA molecule to which the RNA polymerase binds; starts transcription

27. anticodon Region of tRNA that is made of 3 nucleotide sequence complementary to a codon

28. 5 kingdoms of living things Monera Protista Fungi Plantae Animalia

29. Internal fertilization Fertilization of an egg by a sperm that occurs inside the body of a female

30. External fertilization Union of gametes outside the bodies of the parents (ex. Many fish and amphibians)

31. synapsis Pairing of homologous chromosomes during meiosis