Multiple Choice QuestionsThe plant ash is an indication of :
organic matter of plant
waste product
mineral salts absorbed by plants
none of these
C.
mineral salts absorbed by plants
The ash that is left after burning any dry part of the plant in a crucible, contains only mineral elements and is called plant ash. If dried plant parts are heated in silica crucible at 600C, all organic substance vaporize and the remaining plant ash contains only inorganic substances or absorbed mineral elements.
Which of the following element plays an important role in nitrogen fixation
Zinc
Molybdenum
Manganese
Copper
B.
Molybdenum
Molybdenum is a component of nitrogenase and thus brings about fixation of gaseous nitrogen. It also act as enzyme activator of nitrate reductase.
Which one of the following elements is almost non-essential for plants?
Ca
Mo
Zn
Na
D.
Na
Sodium and Iodine are not required by most of the plants.
Sodium (Na) is required by very limited plants as it helps to concentrate carbon- dioxide, but mostly plants use a trace amount to produce metabolism.
Lathyrism is caused by
dal
moth dal
khesari dal
Glycine
C.
khesari dal
Lathyrism is a neurological disease causd by khesari dal (Lathyrus odoratus). It carries an ODAP, also known as β-N-oxalyl-amino-L-alanine, or BOAA which is a neurotoxin (glutamate analogue).
The non- photosynthetic, non- symbiotic N2 fixing bacteria are
Rhodobacter
Spirillum
Azotobacter
All of these
C.
Azotobacter
Azotobacter, Beijerinkia are non photosynthetic, non symbiotic and aerobic nitrogen fixing bacteria.
Clostridium is free living, anaerobic nitrogen fixing bacteria.
Assertion: Nitrogen-fixing bacteria in legume root nodules survive in oxygen-depleted cells of nodules.
Reason: Legheamoglobin completely removes oxygen from the nodule cells.
If both Assertion and Reason are true and Reason is the correct explanation of Assertion
If both Assertion and Reason are true but Reason is not the correct explanation of Assertion
If Assertion is true but Reason is false
If both Assertion and Reason are false.
A.
If both Assertion and Reason are true and Reason is the correct explanation of Assertion
Symbiotic hemoglobin (leghemoglobin) is a hemeprotein found in micromolar concentrations in infected cells of legume roots. This is an essential component for nitrogen fixation by legumes. Leghemoglobin is produced as a result of symbiotic association between bacteroid and plant.
Hydroponics is
cultivation of plants in water
growth of plants towards water
growth of plants away from water
soil less cultivation of plants
D.
soil less cultivation of plants
Hydroponics is soil less cultivation of plants by placing the roots in the nutrient solution.
A metal ion involved in stomatal regulation is :
iron
potassium
zinc
magnesium
B.
potassium
Potassium ions are involved in the stomatal movement. Alongwith negative ions, K+ ions accumulate in guard cells in response to light. Solute potential become more negative, resulting in entry of water by osmosis and the turgid guard cells. Therefore, the turgidity of guard cell open the stomata.
Hydroponics is a
soilless culture
airless culture
waterless culture
none of these
A.
soilless culture
Hydroponics refers to soil-less cultures of plants and growing them on mineral solution
Sulphur is an important nutrient for optimum growth and productivity in
pulse crops
cereals
fibre crops
fibre crops
A.
pulse crops
Sulphur is constituent of certain amino acids. The amino acids form the protein by polymerisation. The pulses are rich in protein.
Switch
