25 POINTS The atom is the basic building block of all matter: The idea that matter was made of tiny separate pieces had been around for many years, but it was John Dalton who wrote the first complete theory about atoms in the early 1800’s. Dalton thought the elements were made of atoms, and diff elements had their own type of atom. It wasn’t until the 1900’s, however, that scientists were able to find proof of the atom. What was Dalton missing from his explanation of atoms that all science explanations needed?

A description of how atoms form

Evidence to support his explanation

Models of atoms to show other scientists

A hypothesis to explain his interpretations

B) Evidence to support his explanation

a

explanation:

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!