The biosphere is the highest level of organization in the hierarchy of life on earth. rank the levels of organization from most complex to simplest. a) ecosystems > communities > populations > organisms b) organisms > populations > communities > ecosystems c) ecosystems > organisms > communities > populations d) populations > communities > ecosystems > organisms cycles connect biological, geological and chemical aspects of organisms in a biosphere. a) ecological b) hydrological c) transpiration d) biogeochemical which example best illustrates the difference between a community and a population? a) the two terms are interchangeable, a population is a community. b) all the people in a town would be a community; all their cattle would be a population. c) all the people in a town would be a community; all the people in a country would be a population. d) all the different animals in a national park would be a community; all of the brown bears in the park would be a population.

cells use diffusion to get substances in and out of themselves. that diffusion will occur across the cell membrane or the outer covering of the cell. because we are talking about the surface of the cell, surface area and volume are  important factors here. as a cell increases in size, its surface area and volume increase as well.  we call that the surface area to volume ratio (sa: vol).  but the catch is that  volume increases at a greater rate than surface  area. in other words, as a cell gets bigger, the sa: vol gets smaller. so a really small cell like bacteria is mostly cell membrane (surface) with very little contents (volume). a really big cell like an egg, is mostly insides with a super thin membrane. so what ends up happening is that the cell cannot efficiently diffuse all of the stuff it needs in/out to survive. therefore cell size is limited to about 100mm. so how do we make organisms bigger than 100mm? cells divide! by dividing and becoming multicellular, organisms are able to grow!   check out the diagrams i attached to see the effect of sa: vol. i hope this ! good luck!

i think the answer is 95 hope this