Bob davison describes the endangered species act (esa) as an effective tool for conserving biological diversity. what is his rationale for the value of focusing on individual species? a) a focus on individual species is cheaper than protecting entire ecosystems. b) establishing public empathy for charismatic species provides an opportunity to educate people about lesser-known species. c) the public is not concerned about the economic costs of individual species recovery. d) the public tends to value intact ecosystems over particular plant and animal species.

B)

Explanation:

The Endangered Species Act of 1973 is an act that enforces the legislation of the Convention on International Trade in Endangered Species mostly on Wild Fauna as well as Flora. That being said Bob Davidson described this act as an effective tool by establishing public empathy for charismatic species provides an opportunity to educate people about lesser-known species, such as the Wild Fauna and Flora.

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!