1Biology 4361 Name:______KEY__________ Exam 1 ID#: ____________________ June 23, 2008 Multiple choice (one point each; indicate the best answer) 1. Which of the following agrees with von Baer’s laws: a. The embryos of mammalian species resemble adult stages of amphibian species. b. General features appear earlier in development than do specialized features. c. both agree d. both disagree 2. The epigenetic theory of development a. required the growth of new structures during development. b. explained the mixture of traits in hybrids. c. was hampered by the perceived need for a “vital force”. d. all of the above. 3. Diploblastic animals lack a. true mesoderm b. true endoderm c. true ectoderm d. germinal epithelium 4. A fate map a. determines whether a particular blastomere will survive. b. predicts the point at which a cell will move to a new location. c. tracks the differentiation pathway for a cell or group of cells. d. tracks the movement of stem cells through differentiation. 5. Cleavage can be described as a. increase in cell number, but no cell growth. b. cell growth, but no increase in cell number. c. nuclear division without cytoplasmic division. d. cytoplasmic division without nuclear division. 6. Transplantation of tissue from one embryo to another of a different species is called: a. heterospecific b. heterochronic c. homospecific d. homochronic 7. Crossing over occurs during which stage of meiosis a. prophase I. b. prophase II. c. anaphase I. d. none of the above28. Eggs (oocytes) generally a. are produced when organisms reach maturity. b. function only as carriers of the female genome. c. provide non-genetic information necessary for early development. d. are produced in numbers equal to sperm. 9. The function of gastrulation is a. to form multiple cell layers. b. to place cells in proper orientation for future development.. c. neither of the above. d. both a and b. 10. When a Dictyostelium pseudoplasmodium is cut in half some of the posterior cells, which were fated to become spores, now become pre-stalk cells. This demonstrates a. determinative development. b. autonomous development. c. mosaic development. d. regulative development. 11. Dictyostelium myxamoebae receive chemical signals from the outside environment which are relayed intracellularly across the cell membrane. This is an example of a. evolvability b. signal transduction c. chemotaxis d. chemosignaling 12. Vertebrates undergo a. syncitial specification. b. conditional specification. c. autonomous specification. d. a blend of conditional and autonomous specification. 13. In organisms with autonomous specification the distribution of _________ determines cell fate. a. egg cytoplasm b. maternal RNA c. egg proteins d. all of the above 14. You discover a Drosophila embryo with no apparent head, but with tails at both ends. A plausible explanation is a mutation that inactivated the _______ gene. a. nanos b. bicoid c. Pax6 d. distal-less 15. Cell-cell adhesion is often mediated by a. carbohydrates b. cadherins c. catenins d. all of the above316. RNA interference pathways probably evolved in response to a. hybridization. b. cross fertilization. c. double stranded RNA viruses. d. double stranded DNA viruses. 17. RNA interference involves which enzyme complex a. dicer b. phosphodiesterase c. endonuclease d. exonuclease 18. Histone de-acetylation ___________ gene transcription. a. allows b. increases c. inhibits d. has no effect on 19. You remove a set of cells from an early embryo and observe that the adult organism lacks the structure that would have been produced from those cells. You conclude that the species undergoes a. autonomous specification. b. syncitial specification. c. conditional specification. d. none of the above. 20. Morpholino-antisense oligomers differ from normal antisense RNA in that they a. degrade quickly, so that transient effects can be studied. b. do not degrade quickly, so that long-term effects can be studied. c. can be visualized using fluorescent microscopy. d. are unable to enter the nucleus. 21. To be considered a morphogen gradient, a substance must have a. a source and a sink. b. the ability to diffuse through the embryo. c. a stimulatory activity on cell growth. d. all of the above 22. If a set of tissues is transplanted to an area of unlike fate, but retains its original fate, the original tissue was considered a. specified and determined b. specified but not determined c. determined but not specified d. determined but not committed 23. A characteristic of stem cells is that they each a. make multiple types of differentiated cells. b. make all types of differentiated cells. c. regenerate copies of themselves. d. die after undergoing mitosis.424. During hnRNA processing, which of the following modifications is made? a. A methylated guanine is added to the 3’ end. b. A methylated guanine is added to the 5’ end. c. A methylated guanine is added to the 3’ end in reverse orientation. d. A methylated guanine is added to the 5’ end in reverse orientation. True / False (1 point each) 25. The first observable cellular activity in the oocyte after fertilization is cytoplasmic rearrangement. True / False 26. Histone methylation represses transcription. True / False 27. Muscles and bones are generally derived from mesoderm. True / False 28. Dictyostelium demonstrate a modified form of syncitial specification. True / False 29. In Drosophila the syncytial blastoderm stage is followed by the cellular blastoderm stage. True / False 30. The light bands seen in polytene chromosomes are heterochromatin. True / False 31. More than one system of specification can be observed in some species. True / False 32. Retroviral vectors are commonly used to create pores in the cell membrane. True / False 33. Gene messages can be detected using in situ hybridization. True / False 34. RT-PCR is used to compare the production of specific proteins in different tissues. True / False 35. The DNA in chromatin consists of repeated sets of about 140 base pairs wrapped around a histone core connected together by a 60 base pair linker (Greg’s question). True / False 36.