Researchers discover another cytokine (x) that is upregulated even more than z as a result of exercise. cytokine x binds to receptors in skeletal muscle to stimulate angiogenesis. after strenuous exercise, local [x] would be least similar to post-exercise [z] in:

What feature of cell theory is best demonstrated in the image

Read the following scenario to answer the following question. in some zoos, rare crosses between a male lion and a female tiger have produced hybrid offspring called "ligers." male ligers are sterile but some female ligers are fertile. in the wild, lion and tiger ranges do not naturally overlap, making such a cross unlikely. furthermore, the solitary behavior of tigers and the social organizations of lions create behavioral differences. applying the biological species concept, the sterility of ligers reveals that a. lions are probably a subspecies of tigers b. tigers and lions are the same species c. a new species called "ligers" is forming d. tigers and lions are separate species

When a population split into two subgroups what is most likely to cause the subgroups to develop different traits?