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

123.

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

Heterocysts are present in

• Riccia

• Ulothrix

• Albugo

• Nostoc

A plant requires magnesium (Mg) for

• Holding cells together

• Protein synthesis

• Chlorophyll synthesis

• Cell wall development

Which is essential for root hair growth?

• Zinc

• Calcium

• Molybdenum

• Sulphur

Molybdenum causes

• mottling

• wilting

• reclamation

• chlorosis

Hydroponics is a

• soilless culture

• airless culture

• waterless culture

• none of these