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An experiment conducted aboard Space Lab in 1983 was the first attempt to grow protein crystals in the low-gravity environment of space.That experiment is still cited as evi- dence that growing crystals in microgravity can increase crystal size: the authors reported that they grew lysozyme protein crystals 1,000 times larger than crystals grown in the same device on Earth. Unfortunately, the authors did not point out that their crystals were no larger than the average crystal grown using other, more standard tech- niques in an Earth laboratory.
No research has yet produced results that could justify the enormous costs of producing crystals on a large scale in space. To get an unbiased view of the usefulness of micro- gravity crystal growth, crystals grown in space must be compared with the best crystals that have been grown with standard techniques on Earth. Given the great expense of conducting such experiments with proper controls, and the limited promise of experiments performed thus far, it is questionable whether further experiments in this area should even be conducted.
According to the passage, which of the followingis true about the Space Lab experiment conducted in 1983?
A.It was the first experiment to take place in themicrogravity environment of space.
B.It was the first experiment in which researchersin space were able to grow lysozyme proteincrystals greater in size than those grown onEarth
C.Its results have been superseded by subsequentresearch in the field of microgravity proteincrystal growth.
D.Its results are still considered by some to beevidence for the advantages of microgravityprotein crystal growth.
E.Its results are considered by many to be invalidbecause nonstandard techniques were employed.
It can be inferred from the passage that the authorwould find the Space Lab experiment more impressiveif which of the following were true?
A.The results of the Space Lab experiment could bereplicated in producing other kinds of crystals inaddition to lysozyme protein.
B.The device used in the experiment produced largercrystals on Earth than it did in space.
C.The size of the crystals produced in the experi- ment exceeded the size of crystals grown inEarth laboratories using standard techniques.
D.The cost of producing the crystals in spaceexceeded that of producing them using standardlaboratory techniques.
E.The standard techniques used in Earth laboratorieswere modified in the Space Lab experiment dueto the effects of microgravity.
Which of the following can be inferred from the passage about the device used to grow crystals in the Space Lab experiment?
A.The device is more expensive to manufacture thanare the devices used in standard techniques in an Earth laboratory.
B.The device has not been used to grow crystals inspace since the Space Lab experiment of 1983.
C.Crystals grown in the device on Earth tend to bemuch smaller than crystals grown in it in space.
D.Crystals grown in the device in space have beenexceeded in size by crystals grown in subsequentexperiments in space using other devices.
E.The experiments in which the device was usedwere conducted with proper controls.
The passage suggests that the author would most prob- ably agree with which of the following assessments ofthe results of the Space Lab experiment?
A.Although the results of the experiment areimpressive, the experiment was too limited inscope to allow for definitive conclusions.
B.The results of the experiment are impressive onthe surface, but the report is misleading.
C.The results of the experiment convincinglyconfirm what researchers have long suspected.
D.Because of design flaws, the experiment did notyield any results relevant to the issue underinvestigation.
E.The results of the experiment are too contradictoryto allow for easy interpretation.
