Question 4Question 4Question 8Question 10The 7.014 Final Exam will be: Wednesday, May 24 9:00 am - 12:00 noon Johnson *YOU MUST BRING YOUR ID. This will be a cumulative, closed book exam. Please bring your PRS devise—we will collect them at the exam. Additional Office hours will be held in the coming week. Times and locations will be posted.2 Question 1 Your ongoing interest in bioluminescent organisms has lead you to study the Hawaiian squid, Euprymna scolopes. Most nocturnal creatures cast shadows under the bright Hawaiian moonlight, and are easy prey to predatory fish. This type of squid can shine light downwards to match the moonlight and avoid casting a shadow thereby decreasing predation. a) In their native ocean environment, the squid feed on a wide variety of small fish and invertebrates. You suspect that the squid is the keystone species in this ecosystem. What experiment could you do to test this theory? What result do you predict? To provide squid for your studies, you maintain a large, self-supporting squid tank. Surprisingly, your tank-raised squid are not luminous. In fact, the glow seen in free living squid is due to a species of bacteria, Vibrio fischeri that live in a specialized light organ within the squid. b) When juvenile squid hatch, ambient water enters the light organ. V. fischeri and the many other bacterial species in this ambient water also enter the light organ and colonize it. All the bacteria initially flourish in this nutrient rich environment, but after 10 hours, only V. fischeri remain in the light organ. i) The interaction between V. fischeri and the other bacterial species initially colonizing the light organ can best be described as _____________________. ii) The interaction between the squid and V. fischeri can best be described as _____________________. iii) Is the light organ of the squid the fundamental niche of V. fischeri. Why? iv) Is the light organ of the squid the realized niche of V. fischeri. Why?Question 2 As the semester comes to a close, you discover some interesting fruit fly mutants around your dorm’s kitchen. Blue eyes and green antennae are two phenotypes new to these mutants. When you cross males with both traits to wild type females you find that all the F1 male offspring have wild type eyes and antennae while all the female offspring have both blue eyes and green antennae: Males with blue eyes and green antennae X normal females All males are normal All females have blue eyes and green antennae a) What is the most likely mode of inheritance for both of these traits? When you cross F1 flies to each other you find the following results for the males in the F2: F1 normal males X F1 blue eyes and green antennae females F2: Out of 250 males: 113 blue eyes, green antennae 112 wild type 12 blue eyes, normal antennae 13 normal eyes, green antennae b) What is the recombination frequency between the genes for the blue eyes and green antennae traits? c) Would you expect to see F2 female flies with blue eyes and normal antennae? Why or why not? 3Question 3 a) Match each of the following structures to the type of molecule it represents: 1) protein 2) RNA 3) DNA CCCC COOCCCONH N NNCHHHHOO(CH ) (CH )CCOONH+CHCHH CHHHHNHCONHNH+CH332222222233OCH2OPONNNNNH2OHHO--HHHOPOO-OHHOH C2HHadeninethymineHOPOO-OHHOH C2HOHHHNHNOONNNNNH2adenineCH3OCH2OPONNNNNH2OHHO--HHOPOO-OHHOH C2HHadenineuracilOPOO-OHHOH C2HOHHNHNOONNNNNH2adenineOHOHOH 4Question 3, continued b) Fill in the blanks in this representation of the central dogma. Choose from: nucleus, translation, RNA, membrane, DNA, cytoplasm, polysaccharide, transcription, or protein This process is ____________________ . In eukaryotes, this process occurs in the _______________________.This process is ____________________ . In prokaryotes, this process occurs in the _______________________. Question 4 In analyzing differences between star squash players and armchair warriors, you have discovered a protein that exists only in the squash players. You design substrates that will bind to the "star protein". CH3CH3CH3HOH N3+OHValGluAsp Alastar proteinsubstrate 1 5Question 4, continued a) Give the name for the strongest intermolecular interaction between the substrate and the following amino acids on the star protein. Choose from ionic bond, covalent bond, hydrogen bond, and van der Waals forces. Amino Acid Strongest interaction i) Val ii) Glu iii) Asp iv) Ala b) You make the following additional substrates Va lGl uAsp Alasta r p rot einsu b str a te 2H N3+SHCH3CH3CH3HODo es t h e ty p e of in ter actio n bet weenthe Ala of the star protein and thesubstrate change with substrate 2 ascompare to substra te 1? ValGluAsp Alastar proteinCH3CH3CH3NH3+H N3++OHsubstrate 3Does the type of interaction betweenthe Glu of the star protein and thesubstrate change with substrate 3 ascompared to substrate 1? c) Which substrate would you expect binds the most tightly to the star protein? substrate 1 substrate 2 substrate 3 Why? 6ALANINE(ala)ARGININE(arg)ASPARAGINE(asN)CCOOHNH3CH3-+CCOOHNH3CHCH3CH3-+CCOOHNH3CH2CH2CH2NHCNH2NH2-++CCOOHNH3CH2CONH2-+CCOOHNH3CH2COO-+-ASPARTIC ACID(asp)CCOOHNH3CH2SH-+CYSTEINE(cys)CCOOHNH3CH2CH2OOC-+-CCOOHNH3CH2CH2OCNH2-+CCOOHNH3H-+CCOOHNH3CH2CNCNHHHH-++CCOOHNH3CHCH3CH2CH3-+CCOOHNH3CH2CHCH3CH3-+CCOOHNH3CH2CH2CH2CH2NH3+-+CCOOHNH3CH2CH2SCH3-+CCOOHNH3CH2HHHHH-+CNCH2CH2CH2HHH-COO+CCOOHNH3CH2OH-+CCOOHNH3CHOHCH3-+CCOOHNH3CH2-+CCOOHNH3CH2OHHHHH-+GLUTAMIC ACID(glu)GLUTAMINE(glN)GLYCINE(gly)HISTIDINE(his)ISOLEUCINE(ile)LEUCINE(leu)LYSINE(lys)METHIONINE(met)PHENYLALANINE(phe)PROLINE(pro)SERINE(ser)THREONINE(thr)TRYPTOPHAN(trp)TYROSINE(tyr)VALINE(val)STRUCTURES OF AMINO ACIDSCNHHHHHHat pH 7.0 78 Question 5 To investigate the yeast metabolic pathway for serine biosynthesis, you screen for serine auxotrophs (mutants which are unable to grow without serine supplied in their growth medium). You isolate four such mutants, and test them for growth on medium supplemented with several intermediates (A, B and C) known to be part of the pathway. The results are shown below ("+" represents growth, "-" represents no growth). Strain minimal medium minimal + A minimal + B minimal + C minimal + serine wild type + + + + + m1 - + + - + m2 - - - - + m3 - + - - + m4 - + + - + You then mate the
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