Which of the following genetically modified organisms has not been developed by
genetic engineers (at least, not yet)?
A) transgenic rice with genes for milk proteins
B) transgenic salmon with a growth hormone gene that allows them to grow more
quickly
C) transgenic corn with the gene for human insulin
D) transgenic pigs with a roundworm gene that allows them to make more omega-3
fatty acids
In 2011, scientists investigated whether the salts that are spread on icy roads to melt the
ice are diluted enough by spring rainfall so that they do not have negative effects on
amphibian species that breed in nearby areas. They exposed clutches (groups of eggs)
of salamanders to three test conditions with varying salt concentrations (road salts
mixed with dechlorinated tap water) to simulate salt concentrations of small pools of
water located near highways that are typically fed by rainareas where salamanders often
lay their eggs. After 9 days, the scientists placed the three groups in “normal” water and
measured how much body mass the salamanders lost every 3 days for 9 days. They
chose to measure change in mass because salamanders are able to take in water, which
helps lower the chances of salamander embryos dying from freezing, disease, or
predation. The table below provides partial results of this study.
What do you predict that group 3 demonstrated?
A) higher mass lost from its initial conditions than group 2
B) the same mass lost from its initial conditions as group 1