The major portion of the dry weight of plants comprises of
carbon, hydrogen, and oxygen.
nitrogen, phosphorus and potassium
calcium, magnesium and sulphur
carbon, nitrogen and hydrogen.
Which one of the following is not essential element for plants?
Potassium
Iron
Iodine
Zinc
The association between blue-green algae and fungi occures in :
lichens
symbiosis
cannibism
mycorrhiza
Which of the following is a flowering plant with nodules containing filamentous nitrogen-fixing micro-organisms?
Casuarina equisetifolia
Crotalaria juncea
Cycas revoluta
Cicer arietinum
The translocation of organic solutes in sieve tube members is supported by
P-proteins
mass flow involving a carrier and ATP
cytoplasmic streamig
root pressure and transpiration pull
Which of the following is not caused by deficiency of mineral nutrition?
Necrosis
Chlorosis
Etiolation
Shortening of internodes
Which of the following is a symbiotic nitrogen fixer?
Glomus
Azotobacter
Frankia
Azolla
Mycorrhiza is a symbiotic relationship between roots of higher plants and
virus
fungi
bacteria
blue-green algae
Stomata of a plant open due to:-
influx of calcium ions
Influx of potassium ions
efflux of potassium ions
influx of hydrogen ions
Which of the following is a free living aerobic non-photosynthetic nitrogen-fixer?
Rhizobium
Azospirillum
Nostoc
