The first stable product of fixation of atmospheric nitrogen in the leguminous plant is
NO2-
ammonia
NO3-
glutamate
Macromolecule chitin is
Nitrogen-containing polysaccharide
Phosphorous containing polysaccharide
Sulphur containing polysaccharide
Simple polysacchaaride
Following are the two statements regarding the origin of life.
II is correct, but I is false
Both I and II are correct
Both I and II are false
I is correct, but II is false
The structures present in the roots to absorb water and minerals is
Epidermal extensions
Hypodermis
Endodermis
Epidermal appendages
Nitrogen-fixation in root nodules of Alnus is brought about by
Bradyrhizobium
Clostridium
Frankia
Azorhizobium
C.
Frankia
Nitrogen is the most critical element. The atmosphere is the greatest reservoir of nitrogen. Molecular nitrogen cannot be utilized directly by plants. It has to be fixed or converted into compounds prior to utilization, Symbiotic nitrogen fixation is accomplished by Rhizobium species, which occurs on the roots of leguminous plants. Certain non-leguminous plants also form nodules to fix nitrogen. The best known example in temperate region is alder (Alnus sp.). The bacteria involved in nodule formation is an Actinomycetes, the Frankia.
Clostridium is anaerobic, saprotrophic, free-living nitrogen-fixing bacteria.
Bradyrhizobium is symbiont in plants of parasponia and soyabean.
The Azorhizobium forms both stem and root nodules in Sesbania (aquatic plant).
Many elements are found in living organisms either free or in form of compounds. One of the following is negligible is living organisms
Silicon
Magnesium
Iron
Sodium
Which of the following is non-symbiotic nitrogen fixer organism?
VAM
Azotobacter
Anabaena
Rhizobium
Which of the following is responsible for biological nitrogen-fixation?
Nife gene
Nitrogenase
Yeast alanin tRNA synthetase
RNA synthetase
‘Sun basket’ is
The device to utilize sun rays directly to meet the requirement of heat energy
The sufficient amount of sunlight stored in a cell
A device of taking a sunbath
All of the above
Chlorosis is produced in the leaves due to the deficiency of Fe, Mg, Mn, S or N of these essential elements, those that are exclusive constituents of chlorophyll molecule are
Fe, S
N,S
Mg, S
Mg, N