BIOA02H3 Lecture : lecture notes according to powerpoint slides

The accumulation of compatible solutes (for example proline) is a major acclimation response of plants to water deficit.

• Describe how compatible solutes alter the water potential of plant cells.

• Develop a time course of response of the major components of water potential during a drydown cycle in the soil and plant root and postulate potential changes in proline concentrations in the cytoplasm, cell Ys and Yp, and the expression of aquaporins.

2. Which one of the following does not correctly match the form with its function?

a. roots: water and minerals in the soil are absorbed

b. phloem sap: products of photosynthesis are transported from roots to shoots

c. leaves: sugars are produced by photosynthesis

d. xylem sap: water and minerals are transported from shoots to roots

3. If you place flaccid plant cells in pure water, water ________ into cell because it has ________.

a. does not enter the cell; solutes and low water potential

b. enter the cell; solutes and high water potential

c. enter the cell; solutes and low water potential

d. does not enter the cell; solutes and high water potential

A hypertonic solution has a higher level of solutes so the water moves out of the cells to the surroundings

A hypertonic solution has a higher level of solutes so the water moves out of the cells to the surroundings

A hypotonic solution has a higher level of solutes so the water moves out of the cells to the surroundings

The salt and water solution in the potato is a hypotonic solution

Osmosis is the movement of large molecules across a membrane which require embedded proteins

The plain water in this experiment is the solvent and the salt is the solute.

Passive transport requires no energy and the molecules move with the concentration gradient or from high concentration to low concentration

Active transport required no energy and the molecules move with the concentration gradient or from high concentration to low concentration.

The water on the inside of the potato with the salt molecules is an isotonic solution the same as the solution on the outside of the potato.

Water will not move by simple diffusion (osmosis) into or out of cells it requires energy or protein transporters

The solution of salt water in the potato has a lower concentration of water molecules so the water on the outside should move into the cells