Classify the following relationship as parasitism, commensalism, mutualism: a spiny sea urchin and a tiny fish that hides from predators by floating among the sea urchin's spines?

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.

If bacteria are much too small to see, what is one reason why can we see colonies in the petri dishes that have plenty of food to eat after only a few days?

(amoeba sisters video recap: pedigrees and need