Contents

The cause of guttation is
a) Transpiration                          
b) higher root pressure
c) high root temperature
d) obstructed xylem

b

Guttation occurs when plants absorb water by
a) active absorption           
b) passive absorption
c) root pressure  
d) both a and b

c

The metal ion involved in stomatal regulation is………
a) Iron                                           
b) magnesium
c) zinc                                           
d) potassium

d

Increase in COconcentration around leaf causes …………
a) rapid opening of stomata
b) partial closure of stomata
c) complete closure of stomata
d) there will be no effect on stomatalopening


c

Which percentage of water absorb by herbaceous plants is lost during transpiration?
a) 90      
b) 70                                              
c) 30     
d) 10


a

Stomata open during the day time because the guard cells………
a) photosynthesize and produce osmotically active sugars    
b) thick walled
c) C shaped                                  
d) covers


a