Which of the following must be true for diffusion to occur? Molecules or particles must have different sizes.

Special protein channels must always be available.

There must be areas of different concentrations.

Energy must be available.

his research revealed two genetically different groups of prokaryotes, which justified splitting kingdom monera into two kingdoms. the genetic and cellular differences were so great, that these two kingdoms were eventually placed into different domains in the current three-domain system.

answer; i do believe that the correct answer is; ///mendelian genes are at specific loci on the chromosome and, in turn, segregate during meiosis;

just finished the test, the answer is d, greg is the least cost-effective because he charges the most for the project

bacterium is not correct