10. RNAimethodologyusesdouble-strandedpieces of RNA to trigger a breakdown or blocking of mRNA. For which of the followingmight it morepossibly be useful? (A) to decrease the productionfrom a harmfulgain-of-functionmutatedgene (B) to form a knockoutorganismthatwill not pass the deletedsequence to its progeny (C) to raise the concentration of a desiredprotein (D) to raise the rate of production of a neededdigestiveenzyme
31. What may probablyhappenwhen the healthypeoplemoveawayfrom the Mediterraneanregion?
(A) They may have no time to do exercise.
(B) Theytend to be moreresponsible for theirhealth.
(C) Theytend to increase the healthadvantages.
(D) Theymighthave a betterchance to get heartdisease and cancer.
AngelinaJolie’s chances of developingbreastcancerwere so highbecause she inherited a mutatedBRCA 1 genefrom her mother, MarchelineBertrand, who died of ovariancancer at the age of 56. The
BRCA1 is present in everyone but onlymutates in one in 1,000 people. Anyonewith the mutation has a
50-80% chance of developingbreastcancer. But Jolie’s riskfigure was calculated to be evenhigherbecause of otherfactors, includingfamilyhistory.
“There are variouscomputerprogramswhere you can inputgeneticinformation, familyhistory and
otherthings and it willcalculate a figure, which is why she’s got thisveryprecisesoundingnumber,” says
Dr. Kat Arney, a seniorsciencemanager at CancerResearch UK.
Breastcancer is already “the top cancer in womenboth in the developed and the developingworld”,
according to the WorldHealthOrganization - and in manycountries, it’s becomingmorecommon.
Overall, a womanliving in the UK has a 12% chance of gettingbreastcancerduring her lifetime. It’s
the same in the US. But increasinglongevity isn’t the onlyreason for the highincidence of breastcancer.
“There is an increase in rates in youngerwomen and it’s for a number of reasons. We knowthatwomen’s lifestyles are changing and beingoverweight and drinking a lot of alcohol is linked to breastcancerrisk,” saysArney.
Changes in reproductivehabits are also a factor. According to CancerResearch UK, the relativerisk of developingbreastcancer is estimated to increase by 3% for eachyear an adultwomandelaysbecoming a mother. Women who breastfeedalsoreducetheirrisk. The longer a womanbreastfeeds,
the greater the protection. It’s estimatedthatrisk is reduced by 4% for every 12 months of
breastfeeding. This may explain why women in richercountrieshave a higherrisk of breastcancer.
Africanwomen are fourtimeslesslikely to get the diseasebecausetheyhavechildren at a younger age,
havemore of them and breastfeedthem for longer.
30. Which of the followingseriesbestreflectswhat we knowabout how the flu virusmovesbetweenspecies?
(A) An avian flu virusundergoesseveralmutations and rearrangementssuchthat it is able to be
transmitted to otherbirds and then to humans.
(B) The flu virus in a pig is mutated and replicated in alternatearrangements so thathumans who eat the
pig products can be infected.
(C) A flu virusfrom a humanepidemic or pandemicinfectsbirds; the birdsreplicate the virusdifferently
and thenpass it back to humans.
(D) An animalsuch as a pig is infectedwithmorethan one virus, geneticrecombinationoccurs, the new
virusmutates and is passed to a new speciessuch as a bird, the virusmutates and can be transmitted to
19. Based on the gene and proteinsequencesthatfollow, whattype of mutation-polypeptideeffect has occurred?
Normalgene: ATGGCCGGCACCGAAAGAGACCMutatedgene: ATGGCCGGCCCGAAAGAGACCNormalprotein: Met-Ala-Gly-Thr-Glu-Arg-Asp
(A)nucleotidedeletion-nonsense (B)nucleotidedeletion-missense (C)nucleotidedeletion-frameshift (D) nucleotideinsertion- missense (E)nucleotideinsertion-frameshift