video 2.7 and 2.8

In osmosis, how does water move across a selectively permeable membrane?

• From an area of lower water concentration to higher water concentration.

• From an area of higher solute concentration to lower solute concentration.

• From an area of higher water concentration to lower water concentration.

• From an area of lower solute concentration to higher water concentration.

Why does a gummy bear expand when placed in a cup of water overnight?

• The sugar in the gummy bear dissolves, making it larger.

• Water moves from the cup (hypotonic) into the gummy bear (hypertonic) by osmosis.

• The gummy bear absorbs water through active transport.

• The gummy bear's gelatin reacts with water, causing it to swell.

What is the primary function of a contractile vacuole in freshwater protists like Paramecia?

• To store excess food particles.

• To regulate the cell's internal temperature.

• To expel excess water that enters the cell by osmosis.

• To facilitate movement through the water.

What process causes guard cells to open stomata?

• Water flowing out of the guard cells, causing them to shrink.

• Guard cells pumping potassium ions in, making them hypertonic, followed by water entering.

• Guard cells releasing hydrogen ions, which directly opens the pore.

• Increased pressure from adjacent cells pushing the guard cells apart.

Which statement accurately describes water potential?

• It is a measure of water's tendency to move from where it is to where it's not, and adding solute increases it.

• It is a measure of water's tendency to move from where it is to where it's not, and adding pressure decreases it.

• It is a measure of water's tendency to move from where it is to where it's not, and water flows from areas of higher to lower water potential.

• It is a measure of the solute concentration in a solution, and it is always a positive value.