Heterocysts in Anabaena is helpful in
secondary growth
nitrogen-fixation
ion uptake
gaseous exchange
The statement given below are the deficiency symptoms of a certain element. Identify the element with the help of options that follow.
I. Stunted growth
II. Tissue necrosis
III. Curling appear first in young leaves
IV. Premature flower abscission
Choose the correct option
magnesium
boron
calcium
nitrogen
The nitrifying bacteria that convert the ammonia to nitrates are
Nitrosomonas and Nitrobacter
Azotobacter
Rhizobium sp.
Thiobacillus denitrificans
The plant ash is an indication of :
organic matter of plant
waste product
mineral salts absorbed by plants
none of these
Hydroponics is
cultivation of plants in water
growth of plants towards water
growth of plants away from water
soil less cultivation of plants
When one element is involved in opening and closing of stomata, the other helps to maintain the ribosome structure. They are
Potassium and calcium
Phosphorus and sulphur
Potassium and magnesium
Iron and magnesium
Iron and magnesium
C.
Potassium and magnesium
Magnesium is absorbed by plants in the form of divalent Mg2+. It activates the enzymes of respiration, photosynthesis and are involved in the synthesis of DNA and RNA. It is a constituent of the ring structure of chlorophyll and helps to maintain the ribosome structure.
Potassium is absorbed as potassium ion (K+). It helps to maintain an anion-cation balance in cells and is involved in protein synthesis, opening and closing of stomata,
activation of enzymes and in the maintenance of the turgidity of cells.