AP Bio Insta-Review Topic 2.8: Tonicity & Osmoregulation

Front

What is tonicity?

Back

Tonicity refers to the ability of a solution to cause a cell to gain or lose water. It is determined by the concentration of solutes in the solution compared to the concentration of solutes inside the cell.

Front

Define isotonic solution.

Back

An isotonic solution has the same solute concentration as another solution, resulting in no net movement of water across the cell membrane.

Front

What happens to a cell in a hypertonic solution?

Back

In a hypertonic solution, the concentration of solutes outside the cell is higher than inside, causing water to move out of the cell, leading to cell shrinkage.

Front

What is a hypotonic solution?

Back

A hypotonic solution has a lower solute concentration compared to another solution, causing water to move into the cell, which may lead to cell swelling or bursting.

Front

Explain osmoregulation.

Back

Osmoregulation is the process by which organisms regulate the water and solute concentrations in their bodies to maintain homeostasis.

Front

What is the role of the central vacuole in plant cells?

Back

The central vacuole stores water, nutrients, and waste products, and helps maintain turgor pressure against the cell wall.

Front

How does water potential influence water movement?

Back

Water potential determines the direction of water movement; water moves from areas of high water potential to areas of low water potential.

Front

What is solute potential?

Back

Solute potential is the measure of the tendency of water to move into a solution due to the presence of solute; it is always negative or zero.

Front

What is the ionization constant (i) for ionic compounds?

Back

The ionization constant (i) for ionic compounds is greater than 1, as they dissociate into multiple ions in solution.

Front

What is the ionization constant (i) for sucrose?

Back

The ionization constant (i) for sucrose is 1, as it does not dissociate into ions in solution.