NAME ___________________________1BIOLOGY 205/SECTION 7 DEVELOPMENT- LILJEGRENFinal Examination – May 6, 2008Write your name at the top of each page. Read each question carefully before answering—i.e.read the instructions. In all answers, be as specific as possible, while respecting the amountof space allotted for each answer. Use of calculators and cell phones is prohibited during theexam. Be sure to sign and abide by the honor code pledge.----------------------------------------------------------1.) (8 pts) Answer the questions that follow, given the following cell lineage diagrams:a.) Draw a circle around the fourth cell division and a triangle around the last cell division totake place in the wild-type lineage. If more than one cell division takes place at the same timefor either of these cell divisions, draw a second circle or triangle, respectively.b.) How many total differentiated cells will be present from the wild-type lineage shown in anadult worm? _________ What about for the mutant #1 lineage? ___________c.) How many cells are described in the wild-type lineage shown? ___________ What aboutfor the mutant #2 lineage? ___________d.) What is the best description of the type of defect in mutant #1?___________________________________________________________________________e.) What is the best description of the type of defect in mutant #2?___________________________________________________________________________wildtypemutant #1mutant #2NAME ___________________________22.) (8 pts) It’s important to remember that proteins have specific jobs to do in the cell. Foreach protein below, indicate which of the following categories best describes its job:(Some categories may not be used.)a. Membrane-bound signal e. MADS-domain transcription factorb. bHLH transcription factor f. Homeodomain transcription factorc. Secreted signal g. Chromatin binding proteind. Transmembrane channel h. Transmembrane receptorAPETALA1 protein _____________ LIN-3 protein ___________________CFTR protein _____________ MyoD protein __________________LAG-2 protein _____________ Hoxa10 protein _________________Polycomb protein __________________ White protein (flies) ___________________3.) (1 pt) The Antennapedia gene is one of the master regulators of segment identity; it isnormally expressed only in the second thoracic segment. In a fly with a gain-of-functionmutation in Antennapedia, what happens? (Circle one)a. Development proceeds normally.b. The legs of the second thoracic segment are transformed into antennae.c. The third thoracic segment is transformed into a second thoracic segment.d. The legs of the third thoracic segment are transformed into antennae.e. The antennae of the head are transformed into legs.4.) (3 pts) We’ve talked about the key contributions of several scientists to our understandingof development. Match the names of the following scientists to their respectivediscoveries. Some names will not be used as answers. (A) John Bowman (E) Ed Lewis(B) Christiane Nüsslein-Volhard (F) John Sulston(C) Oliver Smithies (G) Eliott Meyerowitz(D) Thomas Hunt Morgan (H) Sidney Brenner_____ discovered and characterized numerous mutants that affect the fly body plan_____ determined the entire cell lineage of C. elegans_____ proposed that control of segment identity by homeodomain proteins is conservedbetween flies and vertebrates5.) (3 pts) In a wild-type fruit fly embryo, about 30% of the ectodermal cellsinvaginate to become neuroblasts, and 70% remain behind to become epidermis.a) What are the proportions of neuroblast and epidermis in an embryo homozygous for a loss-of-function mutation in Delta?______________________________________________b) What would be the fate of ectodermal cells in embryos homozygous for a gain-of-functionmutation in Notch? _________________________________________________________c) What would be the fate of ectodermal cells in embryos homozygous for both a loss-of-function mutation in Delta AND a gain-of-function mutation in Notch.____________________________________________________________NAME ___________________________36.) (10 pts) We discussed how the fly body plan is specified by a cascade of factors. Fromearliest to latest, describe the function of each general category of factor, and nameONE actual gene in that category selected from the following list.treetrunk huckleberry ultrabithorax holy graileven-skipped knirps sex drive reduced nanosheadless sparrow odd-skipped engrailed Category Function A gene in this categorya. Maternal effect ___________________________ __________________________b. Gap ___________________________ __________________________c. Pair rule ___________________________ __________________________d. Segment polarity ___________________________ __________________________e. Homeotic ___________________________ __________________________7.) (9 pts) Shown below is the lineage of C. elegans through the 8-cell stage of embryodevelopment.a) (Circle one) All cell fate decisions in the worm were once thought to be determined byconditional (regulative) OR autonomous (mosaic) specification.b) The asymmetric distribution of P-granules is responsible for generating what importantlineage? _______________________ In the picture above, draw a square around thecell(s) in a 2-celled embryo which contain P-granules in wild-type. The _______________mutants affect P-granule segregation in C. elegans. In the picture above, draw a circlearound the cell(s) in a 4-celled embryo which would contain P-granules in these mutants.c) What important lineage is generated by the E cell (a cell normally found in 8-celled wormembryos)? _________________d) Describe the crucial experiment by Bob Goldstein that demonstrated the cell signalingrequired to induce formation of the E cell.e) The secreted signal that induces E cell formation is a homolog of ______________ in flies.NAME ___________________________48.) (10 pts) You’re a scientist in a lab studying Waardenburg’s syndrome I and II.a) What gene(s) could you knockout to generate mouse models of these syndromes?________________________________________b) ES cells, which are crucial for this procedure, are derived from what cell type in blastocystembryos? ________________________________________c) What rare event in ES cells will replace one wildtype
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