Final answer:
Osmotic pressure is the force necessary to stop the movement of solvent, typically water, across a semipermeable membrane from a region of lower solute concentration to one of higher concentration, which is a key concept in osmosis.
Step-by-step explanation:
Osmotic pressure is a concept in biology and chemistry that relates to the movement of solvent, such as water, across a semipermeable membrane. This pressure is a colligative property of solutions and is necessary for understanding various biological processes including how plants maintain their structure and how our cells regulate their water content. When considering osmotic pressure, it is important to understand that solvent molecules naturally move from an area of lower solute concentration to an area of higher solute concentration, in a process called osmosis.
The force required to stop osmosis is called the osmotic pressure. Essentially, osmotic pressure is the pressure that must be applied to a solution to prevent the inward flow of water across a semipermeable membrane. It is the force that counteracts the natural tendency of water to flow from a region with lower solute concentration to one with higher concentration due to differences in solute concentrations.
Therefore, the answer to the student's question: Osmotic pressure is a measure of the force needed to C. stop osmosis.