The measurement of the pressure gradient of two solutions that are separated by a selectively permeable membrane is called... A. Osmolarity
B. Equilibrium
C. Homeostasis
D. Tonicty

Glutamic acid: hydrophilic or hydrophobic? positive, negative, or neutral? valine: hydrophilic or hydrophobic? positive, negative, or neutral?

Which best describes the nucleus of an atom a. it is where all of the particle s of the atom are located b. it is the negatively charged part of the atom c. it is where the electrons and the protons are located d. it is the part of the atom with the greatest mass

What are the student's observations and inferences before he starts his investigation?