Distinguish between Pr and Pfr form;Diffusion pressure Deficit and Water potential;Osmosis and Plasmolysis; Chlorosis and Etiolation

 Q.Distinguish between Pr and Pfr form.   

Pr form

Pfr form

1. It is an inactive form of phytochrome.   2.Being inactive, it does not show phytochrome mediated response.   3.Absorption maxima of it is in red wave region (about 680 nm).   4.It is found diffused throughout the cytosol.     5.It is converted to Pfr form in presence of  red light.   6.On centrifugation (2000Xg) it remains present  in the supernatant.   7.It shows less activity  in presence of urea, metal ions etc.

1. It is an active form of phytochrome.   2.Being inactive, it show phytochrome mediated response.   3.Absorption maxima of it is in far red wave region (about 730 nm).   4.It is usually found in discrete areas of cytosol.   5.It is converted to Pr form in presence of far red light.   6.On centrifugation (2000Xg) it remains present  in the pelletes.   7.It shows more activity  in presence of urea, metal ions etc.

 

Q.Distinguish between Diffusion pressure Deficit  and  Water potential.

Diffusion pressure Deficit	Water potential
1.The difference between  the diffusion pressure of any solution and its pure solvent  in atmosphere is called Diffusion Pressure deficit (DPD).   2.It is measured in “atmosphrere” (atm) unit.   3.It is equivalent to Water potential but with positive value.   4.The direction of water movement is from lower DPD to higher DPD.	1.Water potential is the chemical potential of water.It is also defined as the  difference between free energy of water molecules in pure state and solution state. 2.It is measured in “Bar” unit.   3.It is equivalent to Water potential but with negative value.   4.The direction of water movement is from higher Water potential to lower Water potential.

 

Q.Distinguish between Osmosis and  Plasmolysis.

Osmosis

Plasmolysis

1. Osmosis  is a physical process takes place in both living and non living system.   2.In osmosis the movement of water takes place between two similar solutions of different concentration, which are separated by a semi permeable membrane.   3.Cell shows osmosis when it is placed in to hypertonic or hypotonic  medium.   4.It is of two types exosmosis and endosmosis. 5.Osmosis is very significant for cell, specially for water regulation and water balance.

1.Plasmolysis  is a biological process occur  only in living plant cell.   2. In plasmolysis  water moves outward  through osmosis , resulting in  shrinkage of protoplasm.     3. Cell shows plasmolysis when it is placed in to hypertonic medium.   4.There is no such typification.   5.Plasmolysis generally harmful for plants.

Q.Distinguish between Chlorosis and  Etiolation

Chlorosis

Etiolation

1.Chlorosis is a symptom which characterize a disease or physiological abnormality.   2.In chlorosis chlorophyll molecule is degraded due to deficiency of certain elements like Mg+2, Fe+2, Mn+2, Nitrogen, Potassium etc.   3.In chlorosis non green appearance is observed in entire lamina or interveinal region.   4.During chlorosis no modification of stem is noted.   5.It can be overcomed by supplying the deficient element through any method.

1.Etiolation is a physiological process.     2.Etiolation is caused in green plants when they are grown in dark.Mineral deficiency is not a factor for this process.     3.In case of etiolation entire lamina become colourless.   4.During etiolation the stem become elongated.   5.I t can be avoided if the plant is kept in sun light or proper artificial light.

 

 

Q.Distinguish between Trace  element and Tracer element

Trace  element	Tracer element
1.These are nutrient elements required for plant growth and their various metabolism.   2.They may be supplied through nutrient solution  during deficiency in plant.     3.They are required for plant growth in very minute amounts 100mg/l or less.     4.They are supplied through  liquid medium.	1.These are radioisotopic elements required  for detecting  various metabolic pathways   2.They are produced through radioactivity and  introduced in to the plant artificially through different plant parts.   3.They can be detected by Geiger-Mullar counter or by any other methods.Thus they are traceable in plant system.   4.They may be incubated in plants as gaseous form or liquid form.