Stomata open and close due to
presence of valves
hormonal control
turgor pressure of guard cells
concentration gradient of the gases
Ascent of sap in higher plant takes place through,
Xylem
Phloem
Parenchyma
None of these
Main force for ascent of sap in higher plants is
Root pressure
Transpiration pull
Atmospheric pressure
Capillary force
Which of the following scientists gave vital theories of ascent of sap in plants?
Godlewski
Strasburger
Bose
All the above
The transport of water in plants occurs by the process of ______
transpiration
ascent of sap
guttation
none of these
Cohesive force of water is due to presence of,
Hydrogen bonds between water molecules
Covalent bonds between water molecules
Hydrogen bonds between water and components of xylem walls
The cells that are full of water and rigid are called
support cells
flaccid
turgid
The roots absorb water through
epidermal hairs
root hairs
root xylem
root phloem
Water rises in xylem in the form of
Continuous water column
Discontinuous water column
Water vapours
_________ and _________ are non living plant tissues which help in conducting water and minerals dissolved in water from roots to upper parts of the plant.
Xylem vessels, Tracheids
Pholem vessels, Sieve tubes
Aerenchyma , Sclerenchyma
Collenchyma and Parenchyma
