The function of leghaemoglobin during biological nitrogen fixation in root nodules of legumes is to

• convert atmospheric N₂ to NH₃

• convert ammonia to nitrite

• transport oxygen for activity of nitrogenase

• protect nitrogenase from oxygen

Which one of the following elements is not an essential micronutrient for plant growth?

• Mn

• Zn

• Cu

• Cu

The deficiencies of micro-nutrients, not only affects growth of plants but also vital functions such as photosynthetic and mitochondrial electron flow. Among the list given below, which group of three elements shall affect most, both photosynthetic and mitochondrial electron transport ?

• Cu, Mn, Fe

• Co, Ni, Mo

• Mn, Co, Ca

• Ca, K, Na

Which of the following is correct set of micronutrient for plants?

• Mg, Si, Fe, Cu, Ca

• Cu, Fe, Zn, B, Mn

• Mg, Fe, Zn, B, Mn

• Mo, Zn, Cl, Mg, Ca

The enzyme responsible for atmospheric nitrogen fixation is

• nitrogenase

• hydrogenase

• oxygenase

• carboxylase

Hydroponics is

• nutrient less culture

• water less culture

• soilless culture

• none of these

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

18.

Leghaemoglobin helps in

• imparting colour to floral petals

• protecting nitrogenase from O₂

• destroying bacteria

• transport of food in plants

Insects captured by insectivorous plants fulfil their requirements of

• enzymes

• oxygen

• nitrogen

• water

Which among the following is a rootless plant?

• Nymphaea

• Sagittaria

• Ceratophyllum

• Vallisneria