A food chain contains four trophic levels. The top-most level contains about 300 J of biomass. How much biomass (in J) do you expect to find in the bottom (i. e. primary producer) trophic level? Group of answer choices

30,000

3,000,000

300,000

300

30

Examine the two squirrel populations in the accompanying figure. the populations are separated by a geographic barrier. if after a long period of time the two species are no longer separated, what evidence is needed to determine if speciation has occurred? the figure shows two populations of squirrels separated by a geographic barrier. examine the two squirrel populations in the accompanying figure. the populations are separated by a geographic barrier. if after a long period of time the two species are no longer separated, what evidence is needed to determine if speciation has occurred? the figure shows two populations of squirrels separated by a geographic barrier. polyploidy is creating new species. the two populations are not interbreeding freely. hybrid offspring of the two populations begin to appear. one species will increase into a population size twice as large as the other species.

How can antibodies "remember" a particular bacterial invader or "antigen" on that invader?

When mendel crossed a true-breeding short plant with a true-breeding tall plant all the offspring were tall. which term describes the gene for tallnes?