Multiple Choice Questions<br />1. When water enters the cell, the pressure exerted by its swollen protoplast is<br />a. turgor pressure<br />b. D. P. D.<br />c. osmotic pressure<br />d. Imbibition<br />2. In a fully turgid cell, what will be zero?<br />a. WP<br />b. OP<br />d. Water potential<br />3. In a turgid cell surrounded by pure water, the wall pressure<br />a. increases<br />b. decreases<br />c. fluctuate<br />d. remain unchanged<br />ell?<br />c. TP<br />4. The osmotic pressure of cell sap is more in<br />a. mesophytes<br />b. xerophytes<br />c. hydrophytes<br />d. halophytes<br />5. The protective cover of vacuole is called<br />a. cell wall<br />b. leucoplast<br />c. plasmalemma<br />d. tonoplast<br />diagram.
Answers
Answer:
1.A
2. A
3. D
4.B
5.
Explanation:1. In a fully turgid cell DPD is zero, because osmotic pressure is equal to turgor pressure.
2. When a cell is fully turgid its water potential or DPD becomes zero. When a plant cell is placed in a hypotonic solution, water enters into a cell by osmosis, and as a result turgor pressure develops in the cell which is in solution. The cell membrane becomes stretched and the osmotic pressure of the cell decreases. As the cell absorbs more and more water its Turgor Pressure increases and Osmotic Pressure decreases.
3. When a cell is placed in a hypotonic solution then endosmosis occurs it means water enters in the cell and makes the cell turgid. This entry of water in the cell develops in a cell turgor pressure, which exerts pressure on the cell membrane or on the cell wall.
4. Osmotic pressure is the pressure which stops the movement of a pure solvent by the osmosis to a given solution in contact. Xerophytes are the plants which grow in water scarcity region and need to conserve water. The osmotic pressure of the cell sap is more in xerophytes as they require high suction pressure which is achieved by higher osmotic pressure as high osmotic pressure prevents the movement of water out of the cell and helps in conservation of water.
5. A vacuole is covered by a membrane called tonoplast.
Tonoplast (vacuolar membrane) refers to the cytoplasmic membrane surrounding the large vacuole of a plant cell.
It separates the vacuolar contents from the cytoplasmic contents.
It is a semi-permeable membrane which allows the movement of only certain molecules through them and also helps to maintain turgor pressure in the cell.
So, the correct answer is 'Tonoplast'.