Which of the following would require the use of recombinant dna?

a. crossing two cherry trees to create better cherries.
b. bacteria that make human growth hormone.
c. creating a polyploid orange tree.
d. breeding a honey bee and an african bee to make a killer bee

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

The concept of keystone species is controversial among ecologists because most organisms are highly interdependent. if each of the trophic levels is dependant on all others how can we say one is most important

List five ways we are indebted to phytoplankton