Chapter – 11
Photosybthesis In Higher Plant’s
Q.1. Addition of urea to flowering plants so as to grow faster in earthen pot results in the death of the plant after a while. What can be the cause?
Ans.
Due to exosmosis, the plant dies. Water gradually tends to move out of the plant cell as the solution outside is a hypertonic solution whereas the plant cell is hypotonic. This causes plasmolysis of the cells of the roots and ultimately, the death of the plant.
Q.2. The direction and rate of Osmosis depend upon ________
Ans.
It depends upon both the concentration gradient and the pressure gradient.
.3. Water absorption by dry seeds from soil rises the ______, hence aiding seedlings to appear out of the soil.
Ans.
The seed materials imbibe water which propels the seedlings out of the soil hence the seed swells and imbibition pressure rises within the seeds enabling seed germination.
Q.4. What are solute potential and water potential?
Ans.
The potential energy of water is considered to be the water potential. It is also regarded as a measure of the difference between the potential energy of pure water and a given sample of water. The lowering magnitude of water potential because of the dissolution of solute is known as solute potential.
Q.5. Explain how almost all the water moves into the root?
Ans.
The apoplast pathway causes water to flow in the root as the cortical cells are generally loosely arranged which provides no resistance to the water that moves through the mass flow. It occurs due to cohesive and adhesive properties exhibited by water. The Symplast pathway is also attributed to the movement of molecules of water within the root.
Q.6. Name a molecular movement that is highly selective requiring special membrane proteins without needing any energy.
Ans.
Facilitated diffusion
Q.7. What is Transportation in Plants?
Ans.
The process of distribution or the movement of water, minerals and food to all parts of the plant body is termed Transportation in Plants.
Q.8.How is the transportation process occurs in plants?
Ans.
Transport in plants occurs at three levels:Individual cells are involved in the uptake and release of water and other solutes.Short-distance transport of substances from one cell to another.The xylem and phloem are two tissues responsible for the movement of water and other solutes.
Q.9.What is Translocation?
Ans.
The movement of water and other nutrients from the soil to all parts of the plant is termed Translocation
Q.10.What are the different means of Transportation in plants?
Ans.
There are three different means of Transportation in plants:Diffusion.Facilitated diffusion.Active Transport.
Q.11.Define Plasmolysis and osmosis.
Ans.
Plasmolysis is defined as the contraction of the protoplasm of cells within plants due to the loss of water through osmosis.Osmosis is defined as the process of movement of the molecules from a solution of low concentration to a solution of high concentration through a semipermeable membrane.
Q.2. Name a method that can be used to increase the life span of cut plants in a vase.
Ans.
By quickly transferring them into the water, their lifespan can be increased as air will immediately shift into the tissue that conducts water and fill the cell. In addition, supplying elements and nutrients in varying concentrations can increase its life span. Cytokine, a hormone is sprayed or can be dipped in its solution to delay plant senescence.