Why might you need a planisphere to help determine which constellations are visible in the sky at a certain time of year?

Texas bluebonnet plants seen in this photo are an example of which ecological unit?

Give the biological term for: structures that display characteristics of living organisms only within living cells

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