AP Bio Tonicity and Osmosis

Front

What is tonicity?

Back

Tonicity refers to the ability of a solution to affect the volume and pressure of a cell by osmosis. It describes how the concentration of solutes in a solution compares to that of the cell.

Front

Define isotonic solution.

Back

An isotonic solution is one where the concentration of solutes is equal inside and outside the cell, resulting in no net movement of water.

Front

What happens to a cell in a hypotonic solution?

Back

In a hypotonic solution, water enters the cell, causing it to swell and potentially burst due to increased internal pressure.

Front

What is a hypertonic solution?

Back

A hypertonic solution has a higher concentration of solutes compared to the inside of the cell, leading to water moving out of the cell.

Front

Explain osmosis.

Back

Osmosis is the movement of water molecules across a selectively permeable membrane from an area of lower solute concentration to an area of higher solute concentration.

Front

What is the role of the cell membrane in osmosis?

Back

The cell membrane is selectively permeable, allowing water to pass through while restricting the movement of solutes, thus facilitating osmosis.

Front

What occurs when a cell is placed in a hypertonic solution?

Back

When a cell is placed in a hypertonic solution, it loses water and shrinks, a process known as crenation.

Front

Define solute and solvent.

Back

A solute is a substance that is dissolved in a solution, while a solvent is the substance that dissolves the solute, typically a liquid.

Front

What is the difference between active transport and passive transport?

Back

Active transport requires energy to move substances against their concentration gradient, while passive transport does not require energy and moves substances along their gradient.

Front

What is osmotic pressure?

Back

Osmotic pressure is the pressure required to prevent the flow of water across a semipermeable membrane due to osmosis.