Describe what is meant when water is called a polar molecule

Water is made up of the hydrogen and oxygen element in the ratio of 1:2. Water is the universal solvent that has the ability to dissolve almost all the substances. Water has the bent V shape.

Hydrogen is a polar solvent as it contains the oxygen,  more electronegative element oxygen. Hydrogen is the electropositive element. The electronegativity difference between oxygen and hydrogen makes hydrogen slightly positively and oxygen slightly negatively charged. The polarity of water molecule makes it a polar molecule.

the solute can move "downhill," from regions of higher to lower concentration, relying on the specificity of the protein carrier to pass through the membrane. this process is called passive transport or facilitated diffusion, and does not require energy.