Multiple Choice QuestionsThe free-living, anaerobic nitrogen - fixer is
Beijerinckia
Rhodospirillum
Rhizobium
Rhizobium
Leguminous plants are able to fix atmospheric nitrogen through the process of symbiotic nitrogen fixation. Which one of the following statement is not correct during the process of nitrogen fixation?
Leghaemoglobin scavenges oxygen and is pinkish in colour
Nodules act as a site for nitrogen fixation
The enzyme nitrogenase catalyse the conversion of atmospheric N2 to NH3
The enzyme nitrogenase catalyse the conversion of atmospheric N2 to NH3
D.
The enzyme nitrogenase catalyse the conversion of atmospheric N2 to NH3
Root nodules of leguminous plants harbour symbiotic bacteria, Rhizobium, which fixes atmospheric nitrogen and provides the plant with most or all of its nitrogen requirements. In return, they have access to a rich supply of carbohydrate. The fixation of atmospheric nitrogen (N2) to ammonia (NH3) occurs within the nodules, using the enzyme nitrogen cut this enzyme is very sensitive to oxygen and gets inhibited in oxygen rich environment. This problem is solved by leghaemoglobin, a pinkish-red, oxygen-binding, iron-containing protein present in root nodules. It functions as oxygen buffer, scavenges oxygen and provides the enzyme nitrogenase, a low oxygen environment in which nitrogen fixation can occur.
Manganese is required in
nucleic acid synthesis
plant cell wall formation
photolysis of water during photosynthesis
photolysis of water during photosynthesis
Which of the following is a symbiotic nitrogen fixer?
Glomus
Azotobacter
Frankia
Frankia
Nitrogen-fixation in root nodules of Alnus is brought about by
Bradyrhizobium
Clostridium
Frankia
Frankia
The two subunits of ribosome remain united at a critical ion level of
Copper
Manganese
Manganese
Manganese
Which one of the following elements is not an essential micronutrient for plant growth?
Mn
Zn
Cu
Cu
Examination of blood of a person suspected of having anaemia, shows large, immature, nucleated erythrocytes without haemoglobin. Supplementing his diet with which of the following is likely to alleviate his symptoms?
Thiamine
Folic acid and cobalamine
Riboflavin
Riboflavin
Sulphur is an important nutrient for optimum growth and productivity in
pulse crops
cereals
fibre crops
fibre crops
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