A cell increases in volume if the external medium is
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Solution
If the plasmolysed cell (flaccid cell) is placed in hypotonic solution then endosmosis occurs, which makes the cell again turgid (volume increases)
Guttation is the result of :
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Solution
The main cause of guttation in plants is root pressure.During night when root pressure is high sometimes due to this high pressure watery drops ooze out with the assistance of special structures which help in guttation called hydathodes.
Osmotic pressure of a solution is
Guard cells help in:
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Solution
Guard cells help in transpiration. Transpiration is the evaporation of water from the aerial parts of plants,especially leaves but also stems, flowers and roots.Stomatal opening allowing the diffusion of carbon dioxide and oxygen during photosynthesis.
The rupture and fractionation do not usually occur in the water column in vessel/tracheids during the ascent of sap because of
The rupture and fractionation do not usually occur in the water column in vessel/tracheids during the ascent of sap because of
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Solution
The rupture and fractionation do not usually occur in the water column in vessel/ tracheids during the ascent of sap because of cohesion and tension. The water mol-ecules have a great mutual attraction with each other or in other words we can say that they have tremendous cohesive power which is sometimes as much as 350 at-mospheres. Thus, the transpiration pull develops a negative pressure in the uppermost xylem cells. It is transmitted from there into the xylem of stems, and from thereto the roots.
Wilting occurs when
The rate of transpiration in plants is dependent upon
The translocation of organic solutes in sieve tube members is supported by
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Solution
P-protein is the supporting factor for the translocation of organic solutes in sieve tubes
The ability of the Venus fly trap to capture insects is due to:
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Solution
Bending of tentacles in Venus fly trap or Drosera after coming in contact with an insect is thigmonastic or chemonastic movement of variation or Turgor movements.
The mechanism by which the trap snaps shut involves a complex interaction between elasticity,turgor and growth. In the open, untripped state, the lobes are convex, but in the closed state, the lobes are concave. It is the rapid flipping of this bistable state that closes the trap,but the mechanism by which this occurs is still poorly understood. When the trigger hairs are stimulated, an action potential involving calcium ions is generated,which propagates across the lobes and stimulates cells in the lobes and in the midrib between them.