Question

freeze tolerance
use the information and your knowledge of science to answer the questions.
doug schemske is a biologist who studies plants from around the world. doug and his research team carry out experiments with the plant species mouse - ear cress, or arabidopsis thaliana. they like this species because it is easy to grow in both the lab and field. arabidopsis is very small and lives for just one year. it grows across most of the globe and in a wide range of latitudes and climates. arabidopsis is also able to pollinate itself and produce many seeds, making it possible for researchers to grow many individuals to use in their experiments.
doug chose arabidopsis populations in scandinavia and the mediterranean for his research on local adaptation because those two locations have very different climates. the populations may have adapted to have the highest survival and reproduction based on the climate of their home location.
to deal with sudden freezes and cold winters in scandinavia, plants may have evolved freeze tolerance traits, which produces chemicals that act like antifreeze. these chemicals accumulate in their tissues to keep the water from turning into ice and forming crystals. to see whether freeze tolerance was driving local adaptation, doug set up an experiment to identify which plants survived after freezing. doug collected seeds from several different populations across scandinavia and the mediterranean.
doug predicts that if freeze tolerance traits were driving local adaptation, the seedlings originally from colder latitudes would have increased survival after freezing, and seedlings originally from lower latitudes would have decreased survival after the freeze.
select the statement that best supports his prediction.
a the mediterranean plants arent normally exposed to cold temperatures, so they wouldnt have evolved freeze tolerance traits.
b the mediterranean plants are only able to survive in warm environments.
c the mediterranean plants have the genes for freeze tolerance traits, however the genes are not turned on in the warm environment.
d the scandinavian plants do not freeze due to their ability to mutate genes depending on the environment.

Explanation:

Doug's prediction relies on local adaptation: plants from colder regions (Scandinavia) evolved freeze tolerance, while those from warm regions (Mediterranean) did not, leading to lower survival after freezing for the latter. Option A directly supports this by stating Mediterranean plants (from lower, warmer latitudes) have no exposure to cold, so they never evolved freeze tolerance traits, which aligns with the expected lower survival after freezing. Option B is too absolute (they can't only survive in warm environments, just not adapted to cold). Option C contradicts the prediction by saying they have the genes but don't use them, rather than lacking the traits. Option D incorrectly describes the Scandinavian plants' adaptation mechanism.

Answer:

A. The Mediterranean plants aren't normally exposed to cold temperatures, so they wouldn't have evolved freeze tolerance traits.