FREE NEET Biology Practice MCQ Test: Mineral Nutrition Exercise 1 Questions Answers With Detailed Explanations [PDF]

Answer: (b)

Answer: (a)

None of the options is correct. Macronutrients are essential elements which are present in easily detectable quantities, 1-10 mg per gram of dry weight. The macronutrients include carbon, hydrogen, oxygen, nitrogen, phosphorus, sulphur, potassium, calcium and magnesium. Micronutrients or trace elements, are needed in very small amounts (equal or less than 0.1 mg/gm of dry matter). These include iron, manganese, copper, molybdenum, zinc, boron, chlorine and nickel.

Answer: (c)

$N_{2}$ - fixation is accomplished with the help of nitrogen-fixing microbes, mainly Rhizobium. The enzyme nitrogenase which plays an important role in biological $N_{2}$ fixation is very sensitive to oxygen.

Answer: (c)

Answer: (d)

Answer: (c)

Answer: (d)

Copper is absorbed on the clay particles as divalent cations, from where it can be absorbed by the plants by exchange mechanism. It is constituent of plastocyanin which takes part in electron transport during photosynthetic phosphorylation.

Manganese is absorbed by the plants when it is in the bivalent form. Manganese participates in the photolysis of water in pigment system II during photosynthesis and thus it helps in the electron transport from water to chlorophyll.

Iron is mainly available in the ferrous form and it is absorbed in the ferric form, also. It is a part of catalases, peroxidases, cytochromes etc. and plays a role in electron transport system in photosynthesis.

Answer: (c)

Answer: (d)

Answer: (c)

Leghaemoglobin is red colour haemoglobin like pigment which absorbs oxygen and protect nitrogenase enzyme from the oxygen.

Answer: (b)

Answer: (c)

Answer: (a)

Answer: (c)

Plants show deficiency symptoms of an element when that particular nutrient is either not available to the plants or if is available, the plant is not able to use it. sulphur is needed by young leaves, stem and root tips. Its deficiency symptoms which include

1. reduced growth
2. extensive root growth
3. hard and woody stem
4. chlorosis of young leaves

The immobile elements are transported in plant to the tip level, thus their deficiency appears first at the tips of growing apices of roots and shoots.

Answer: (d)

Nitrogen is the mineral element required by plants in the greatest amount. It is absorbed from the soil by the plant in the form of nitrate.

Answer: (b)

Answer: (b)

Answer: (c)

Answer: (c)

Deficiency symptoms appear first in young leaves and young tissues in case of elements which are relatively immobile inside the plant e.g., Ca, S. For mobile elements like N and K, deficiency symptoms first appear in old and senescent leaves as the elements are mobilised from senescing regions for supply to young tissues.

Answer: (c)