This is a species whose presence is critical to the integrity of the community. without this species, the ecosystem may cease to exist.

Which of the following is true of microbes? a. ninety-nine percent of all microbes are pathogenic.b. gene expression in bacteria is very similar to gene expression in humans, which facilitates the use of bacteria in recombinant biotechnology and gene therapy.c. all bacterial enzymes are harmful to humans and the environment.d. microbes create pollutants and toxins that harm the environment.

When a human or animal consumes food, the carbon in that food is most likely to be converted into which of the following elements? a. carbon remains carbon b. nitrogen c. oxygen d. hydrogen

What environmental cues and landmarks do the geese use to determine the timing and direction of their migration over the mountains? how do they find their way?