NCERT Solutions for Class 11 Biology Chapter 12
NCERT Solutions for Class 11 Biology Chapter 12 Mineral Nutrition in PDF file format to free download or Study online without downloading updated for new academic session 2020-2021.Download NCERT Solutions of other subjects and latest NCERT Books also. Ask your queries in Discussion Forum to share your views with your friends.
NCERT Solutions for Class 11 Biology Chapter 12
|Chapter 12:||Mineral Nutrition|
Class 11 Biology Chapter 12 Solutions in English
NCERT Solutions for Class 11 Biology Chapter 12 in PDF form free download in English Medium. NCERT Books 2020-2021 as well as Offline Apps are also available to download in PDF form following the latest CBSE Syllabus. Join the discussion forum to ask your doubts and generate a poll to know the view of other users. NIOS is the option to complete your schooling from home.
Important Terms on Mineral Nutrition
1. Autotroph: An organism that sythesize its required nutrients from simple and inorganic substance; Example-plants, blue green algae (cyanobacteria)
2. Heterotroph: An organism that cannot synthesise its own nutrients and depend on others. Example-Bacteria, protists, members of animalia.
3. Biological nitrogen fixation: Conversion of atmospheric nitrogen into organic compounds by living organisms.
A process of conversion of nitrate into nitrous oxide and nitrogen gas (N2).
Leg-hemoglobin: Pinkish pigment found in the root nodules of legumes.
1. Conversion of ammonia (NH3) into nitrite and then to nitrate.
It acts as oxygen scavenger and protects the nitrogenase enzyme from oxidation.
2. Mineral Nutrition: Plants require mineral elements for their growth and development. The utilization of various absorbed ions by a plant for growth and development is called mineral nutrition of the plant.
3. Hydroponics: Soil-less culture of plants, where roots are immersed in nutrient solution (without soil) is called hydroponics. The result obtained from hydroponics may be used to determine deficiency symptoms of essential elements.
1. The movement of ions is called flux. Influx is inward movement of ions into the cells and efflux is the outward movement of ions.
2. Inhibition of cell division: Deficiency of N, K, S. and Mo.
3. Necrosis: Death of tissues particularly leaf tissue due to deficiency of Ca, Mg, Cu, K.
4. Delayed Flowering: due to deficiency of N, S, Mo.
Criteria for essentiality
1. The element must be necessary for supporting normal growth and reproduction.
2. Requirement must be specific and not replaceable by another element.
3. The element must be directly involved in the metabolism of the plant.
Important Terms related to Chapter 12
1. Chlorosis: Yellowing of leaves due to loss of chlorophyll.
2. Active Transport: Absorption occurring at the expense of metabolic energy.
3. Passive Transport: Absorption of minerals with concentration gradient by the process of diffusion without the expense of metabolic energy.
Important Questions on 11th Biology Chapter 12
Micronutrients: They are also called trace elements and are present in plant bodies in very small amounts, i.e., amounts less than 10 m mole kg– 1 of dry matter. Examples include cobalt, manganese, zinc, etc.
Beneficial nutrients: They are plant nutrients that may not be essential, but are beneficial to plants. Sodium, silicon, cobalt and selenium are beneficial to higher plants.
Toxic elements: Micronutrients are required by plants in small quantities. An excess of these nutrients may induce toxicity in plants. For example, when manganese is present in large amounts, it induces deficiencies of iron, magnesium, and calcium by interfering with their metabolism.
Essential elements: These elements are absolutely necessary for plant growth and reproduction. The requirement of these elements is specific and non-replaceable.
They are further classified as macro and micro-nutrients.
Inhibition of cell division
Stunted plant growth
Chlorosis or loss of chlorophyll leads to the yellowing of leaves. It is caused by the deficiencies of nitrogen, potassium, magnesium, sulphur, iron, manganese, zinc, and molybdenum.
Necrosis is the death of plant tissues as a result of the deficiencies of calcium, magnesium, copper, and potassium.
Inhibition of cell division is caused by the deficiencies of nitrogen, potassium, sulphur, and molybdenum.
Delayed flowering is caused by the deficiencies of nitrogen, sulphur, and molybdenum.
Stunted plant growth is a result of the deficiencies of copper and sulphur.
In a similar way, the deficiency of a nutrient can cause the same symptom as that caused by the deficiency of another nutrient. For example, necrosis is caused by the deficiency of calcium, magnesium, copper, and potassium.
Another point to be considered is that different plants respond in different ways to the deficiency of the same nutrient.
Hence, to identify the nutrient deficient in a plant, all the symptoms developed in its different parts must be studied and compared with the available standard tables.
During the initial phase or apoplast, there is a rapid uptake of nutrients from the soil into the free spaces of plant cells. This process is passive and it usually occurs through trans-membrane proteins and ion-channels.
In the second phase or symplast, the ions are taken slowly into the inner spaces of the cells. This pathway generally involves the expenditure of energy in the form of ATP.