Students can go through AP Inter 2nd Year Botany Notes 2nd Lesson Mineral Nutrition will help students in revising the entire concepts quickly.
AP Inter 2nd Year Botany Notes 2nd Lesson Mineral Nutrition
→ All living organisms require macromolecules such as carbohydrates, proteins and fats along with water and minerals for their growth and development.
→ The Technique of growing plants in a specified nutrient solution is known as hydroponics.
→ Macronutrients include C, H, O, N, P, K, Ca, Mg and S.
→ Micronutrients include Fe, Mn, Cu, Ho, Zn, B, Chlorine and Nickel.
→ C, H and O are called structural elements.
→ Mn and phosphorous are energy-related chemical compounds in plants.
→ Nickel acts as an activator for urease, an important enzyme of Nitrogen Metabolism.
→ The concentration of critical element below which plant growth is retarded is termed as critical concentration.
→ The deficiency symptoms of Nitrogen, Potassium and Magnesium are visible first in the senescent leaves.
→ The deficiency symptoms of Sulphur and Calcium appear first in young leaves.
→ Chlorosis is the loss of chlorophyll leading to yellowing of leaves.
→ Necrosis or death of the tissue occurs due to deficiency of Ca, Mg, Cu, K.
→ Deficiency of Nickel shows Mouse ear in pecan.
→ Minerals are absorbed either by passive or by active process.
→ Mineral salts are translocated through the xylem along with the ascending water which is pulled up through the plant by transpiration pull.
→ The majority of the nutrients that are essential for plant growth and development are available from soil due to weathering and breakdown of rocks.
→ Nitrogen is the most prevalent element in living organisms.
→ The enzyme, nitrogenase which is capable of N2 reduction in present exclusively in prokaryotes. They are called N2 fixers.
→ The enzyme nitrogenase is a Mo-Fe protein and catalyses the conversion of atmospheric nitrogen to ammonia.
→ Nitrogenase enzyme is protected from oxygen by leg-haemoglobin.
→ Amides (asparagine, glutamine) contain more nitrogen than amino acids. So they are transported to other parts of the plant via xylem vessels.
→ Mineral Nutrition is the absorption, distribution and metabolism ef various minerals from soil and atmosphere by plants.
→ Inorganic nutrients are obtained from the air to the plants.
→ The elements required in large quantities are called macronutrients.
→ The elements required in small quantities are called micronutrients.
→ These elements are the constituents of carbohydrates, proteins and fats.
→ Plants absorb minerals through roots by either passive or active processes.
→ These minerals are carried to alt parts of plants through xylem.
→ Nitrogen is very essential element for plant life. But plants cannot use atmospheric nitrogen directly.
→ Nitrogen Fixation: In this process, atmospheric nitrogen is converted into ammonia, that is used as a nutrient for plants.
N2 + 8H+ + 8e– + 16ATP >2NH3 + H2 + 16ADP + 16Pi
→ The enzyme nitrogenase plays an important role in nitrogen fixation.
→ Entry of oxygen towards nitrogenase is prevented by a chemical called leg-haemoglobin.
→ Formation of root nodule: [IPE|
- The roots of host Legume release sugars and amino acids which attract Rhizobia.
- They multiply and get attached to the epidermis of root hair cells and then into the cortex.
- The bacteria initiate nodule formation in the cortex of the root.
→ Synthesis of amino acids by plants involves (i) Reductive amination (ii) Transamination [IPE]
→ Ca is essential for the growth of the root tip. [NEET-2016]
→ Deficiency symptoms of nitrogen and potassium are visible first in senescent leaves. [2014]
→ The first stable product of fixation of atmospheric nitrogen in leguminous plants is N02 [NEET-2013]
→ Potassium is responsible for maintaining turgor in cells. [NEET-2018]
→ The products of reaction catalysed by nitrogenase in root nodules of leguminous plants are ammonia and hydrogen. [NEET-2020]
→ For its action, nitrogenase requires high input of energy. [2012 PMT]
→ An element playing important role in nitrogen fixation is molybdenum. [2010 PMT]