EXAM 3 Study Guide BIOLOGY 10 – FALL 20101. When you started out, you were a single cell. You are now made of many cells; some of these cells function as liver cells, some as muscle cells, some as red blood cells. What name is given to the process that is responsible for this cellular differentiation 2. The process by which genotype becomes expressed as phenotype is ______. gene expression 3. What is a difference between embryonic and adult stem cells? Embryonic stem cells are undifferentiated; adult stem cells are partially differentiated. 4. What name is given to cancer-causing genes? oncogenes 5. Tobacco is responsible for more cancers than any other carcinogen. True 6. Developmental similarities among very different animals can be attributed to ______. shared homeobox genes 7. Which of these mechanisms of controlling gene expression occurs outside of the nucleus? translation 8. What is recombinant DNA? DNA that carries genes from different organisms 9. Which of these is a transgenic organism? an organism carrying a gene that was acquired by artificial means 10. Restriction enzymes are obtained from ______. bacteria 11. Gel electrophoresis separates DNA fragments on the basis of differences in their ______. length 12. Humans and chimpanzees share about ______ of their DNA. 95%-99% 13. Ethical dilemmas raised by DNA technology and knowledge of the human genome include ______. A. the potential for interfering in evolution B. the safety of GM foods C. the appropriateness of creating new plants, animals, and microorganisms D. the potential discrimination against people predisposed to certain diseases E. All of the choices are issues raised by current DNA technology and knowledge of the human genome. 14. Natural selection can be defined as ______. descent with modification15. Homology is evidence of ______. common ancestry 16. The similarity of the embryos of fish, frogs, birds, and humans is evidence of ______. common ancestry 17. Natural selection always results in ______. offspring better adapted to their parents' environment than were their parents 18. Which of the following is a population? the termites infesting your house 19. The ultimate source of all variation is ______. mutation 20. The founder effect differs from a population bottleneck in that the founder effect ______. involves the isolation of a small colony of individuals from a larger population 21. What does Darwinian fitness measure? reproductive success 22. The first genetically engineered pharmaceutical product wasA. human insulin C. pig insulin E. growth hormoneB. penicillin D. a steroid23. Biological species consist of groups of ______. A. families B. individuals C. populations D. genera E. phyla 24. On what basis are populations assigned to the same biological species? they can interbreed and produce fertile offspring 25. A reproductive barrier that prevents species from mating is an example of ______. a pre-zygotic barrier 26. The type of reproductive barrier that occurs when two species mate but fail to produce fertile hybrids is referred to as ______. a post-zygotic barrier 27. Speciation requires ______. genetic isolation 28. Which of the following describes allopatric speciation? A population of squirrels is separated by the Grand Canyon. Through time the two subpopulations evolve into two distinct species. 29. A period of mass extinction is often followed by ______. a massive increase in new species 30. The science of naming organisms is called ______. taxonomy31. The wing of a bald eagle is ______ the wing of a penguin. homologous to 32. Evolution is based on ______. evidence 33. Speciation as a result of genetic isolation without geographic isolation is referred to as ______. sympatric speciation 34. Which of the following is NOT a plant adaptation to a terrestrial existence? photosynthesis 35. The ______ helps plants retain water. cuticle 36. Which of the following correctly illustrates the sequence of the origin of modern groups of plants? bryophytes, ferns, angiosperms, gymnosperms 37. Which of the following lack vascular tissue? mosses 38. Gametophytes are ______; sporophytes are ______. male . . . female 39. ______ are seedless vascular plants. Ferns 40. Which of these adaptations to a terrestrial existence evolved most recently? seeds 41. What is pollen? a male gametophyte 42. ______ were the first plants that did not require water for transferring sperm to eggs. Gymnosperms 43. The parts of a flower include all of the following EXCEPT ______. A. sepals B. cones C. petals D. stamens E. carpels 44. Which of the following is NOT a component of the female structure of a flowering plant? A. style B. stamen C. ovary D. carpel E. stigma 45. What is the function of fruit? It is a mechanism for the dispersal of seeds. 46. Nearly all food plants are classified as ______. angiosperms 47. Nutritionally, all fungi are ______. heterotrophs48. Like plants, fungi have ______; however, in plants it is composed of ______, whereas in fungi it is composed of ______. cell walls . . . cellulose . . . chitin 49. What is a hypha? the basic structure of fungal bodies 50. The large woody cones of the gymnosperms are the male