is an explanation of crime that assumes crime and victimization are highest in places where three factors come together in time and place: motivated offenders, suitable or attractive targets, and absence of a guardian.

Routine Activity Theory

Explanation:

Routine Activity Theory was first proposed by Marcus Felson and Lawrence E. Cohen.This theory focuses the situation in crime.According to this theory crime occurs when three elements converge:

1)a motivated offender

2)a suitable target and

3)an absence of guardian

This theory includes the routine activity of both the victim and offender.And lack of any of the three elements mentioned above is enough to prevent a crime.

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!