Researchers studying rock pocket mice across a 35 kilometer transect in the Arizona Sonoran Desert trapped a total of 225 mice a
nd recorded substrate color and coat-color frequencies for each location. Each site was separated from any of the others by at least eight kilometers. Their data are summarized below. Collecting site Substrate color Number light phenotype Dark phenotype
1 Light 6 6 6
2 light 85 80 5
3 Dark 7 0 7
4 Dark 5 0 5
5 Dark 45 3 42
6 Light 77 34 43
Calculate the overall frequencies of dark-colored mice and light-colored mice caught on dark-colored substrates.
Like the plasma membrane, organelle membranes function to keep the inside "in" and the outside "out." This partitioning permits different kinds of biochemical reactions to take place in different organelles.