Why are ecologists unsettled on whether or not there are any truly commensal interactions among organisms?

Atypical human cell is approximately 12.00 μm in diameter and enclosed by a membrane that is 5.000 nm thick. (a) what is the volume of the cell including the membrane? (b) what is the volume of the cell membrane? (c) what percent of the total volume does its membrane occupy? to simplify the calculations, model the cell as a sphere. enter your answers using four significant figures.

Which of the following is an effect of the uneven heating of the earth by the sun? a sea breeze a land breeze a convection current all of the above

Sexual reproduction in the parent cell will result in offspring with a) identical genetic information. b) half the genetic information. c) double the genetic information. d) four times the genetic information.