Movement of Substance Quiz 4

Active transport is the process in which energy is used to move the particles of a substance across a membrane from a region of lower concentration to a region of higher concentration.

Osmosis the movement of water molecules from a region of higher concentration of water to a region of lower concentration of water through a partially permeable membrane. Diffusion occurs down a concentration gradient with or without a membrane. Active transport is the movement of molecules against a concentration gradient using energy produced by living cell.

When the solution has the same water potential as potato tissue, it is an isotonic solution. Since there is no net loss of water from the cells, there is no further decrease in the length of potato tissue.

5% glucose solution has a higher water potential then 10% glucose solution. Water molecules move into the cell down of water potential gradient across the partially permeable cell membrane by osmosis. Cell wall is a fully permeable structure which allow all substances to enter.

Active transport involves the transport of solute molecules against the concentration gradient i.e. from low to high concentration, using energy obtained from the oxidation of glucose by oxygen during tissue respiration.

In distilled water (a hypotonic solution) water gained by osmosis causes the red blood cells to enlarge and finally burst, resulting in a homogenous solution with no blood cell at all. In salt water (a hypertonic solution), the red blood cell lose water by osmosis and shrink. The spinning causes the shriveled cells to clamp together and sink to the bottom of the tube.

The cells are shrinking. Water has moved from the cytoplasm into the external liquid, this liquid must be more concentrated than the cytoplasm.

3 is plasma membrane, which is semi permeable. Water moves from the region outside the root hair (1) to sap vacuole (4) by osmosis.

Active transport is the movement of substances from a region of lower concentration to a region of higher concentration.

Osmosis occurred. Water molecules move into the more concentrated salt solution through a partially permeable membrane, causing the volume of liquid in tube X to rise. The number of water molecules in the salt solution increases, resulting in a less concentrated salt solution.