[Biology Class Notes] on Nutrition in Plants Pdf for Exam

Plants are like all other living things. They also need food for their growth and development. For the survival of the plants, they also require 16 essential elements. Some of these elements are Carbon, Hydrogen, and Oxygen, which are derived from the atmosphere and soil water.

There are also thirteen essential elements, such as nitrogen, phosphorus, calcium, potassium, magnesium, iron, sulfur, manganese, zinc, copper, boron, molybdenum, and chlorine. These elements are provided either from soil minerals and soil organic matter or by organic or inorganic fertilizers.

 

To utilize these nutrients efficiently, plants also require light, heat, and water. These factors must be adequately supplied. In crop production, some of these factors play important roles such as cultural practices and control of diseases and getting rid of insects.

Modes of Nutrition

We can define nutrition as it is the procedure of gaining food and applying it to grow, repair any damaged body part, and stay healthy. Some processes are involved in the nutrition of plants as they produce their food by taking raw materials from their surroundings, such as minerals, carbon dioxide, water, and sunlight. 

The Two Modes of Nutrition are:

• Autotrophic – Plants are called the primary producer as they exhibit autotrophic nutrition. Also, plants synthesize their food by using light, carbon dioxide, and water.

• Heterotrophic – Under this category, animals and human beings are included as they depend on plants for their food.

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Plant Nutrients

For plant nutrition, some major sources are there. A plant converts the atmospheric CO₂ into simple sugar by using the energy of the sun. Carbon dioxide (CO₂) enters through the stomata. Oxygen (O₂) is also a product of photosynthesis. It is an atmospheric component that also moves through the stomata. 

 

In plants, oxygen is used in cellular respiration to release energy from the chemical bonds in the sugar to support growth and maintenance in the plant. The only reason is that CO₂ and light energy are not sufficient for the synthesis of all the molecules a plant needs.

 

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It is also proven that plants require many inorganic nutrients. We call these elements macronutrients. These organic nutrients are required for the plants in relatively large amounts. Other micronutrients are also required in trace amounts.

Scientists have collected around nine macronutrients, such as Carbon, Hydrogen, and Oxygen, the three elements found in all organic compounds as well as nitrogen.

Soil

Soil composition plays an important role in a plant’s growth. We can define the soil as it is the highly weathered outer layer of the earth’s crust. 

 

Soil is made of a mixture of ingredients, which may include sand, rocks of various sizes, clay, silt, hummus, and various other forms of mineral and organic matter. Also, some pore spaces are there containing water, and air occurs between the particles.

Nitrogen Nutrient Functions

• Nitrogen is an important nutrient for plants. It is biologically combined with C, H, O, and S to create amino acids, which are the building blocks of proteins. 

• Plants are using the amino acids to form protoplasm, the site for cell division, and thus for plant growth and development.

• Nitrogen is desired for all the enzymatic reactions in a plant as all the plants’ enzymes are made of proteins.

• N is necessary for photosynthesis as it plays a major part in the chlorophyll molecule.

• To form several vitamins in plants during photosynthesis, N is the necessary component for them.

• Nitrogen helps the plant to improve the quality and quantity of dry matter. They are available in leafy vegetables and protein in grain crops.
  

Phosphorus Nutrient Functions

• P plays a major role in photosynthesis and respiration. It also helps in energy storage and transfers them as ADP, ATP (adenosine di-phosphate and biphosphate), DPN, and TPN (di – phosphotyrosine and tri – phosphotyrosine nucleotide).

• RNA and DNA structures are the major components of genetic information. P helps the plants to carry the genes.

• P is found in seeds with the highest concentration in a mature plant. A huge amount of P is required in young cells, such as shoots and root tips as in here, the metabolism is high, and cell division is rapid.

• Phosphorus takes part in root development, flower initiation, and seed and fruit development.

• Phosphorus helps to reduce disease probability among some plants. It has been found to improve the quality of certain crops.
  

Do You Know?

We have found some awesome facts about plants. A plant is unique and has an optimum nutrient range as well as a minimum required level. When the plants reach a minimum level, then they start to show nutrient deficiency symptoms. 

 

Too much consumption of nutrients can also cause poor growth because of toxicity. That is why the appropriate amount of application and placement of the nutrients is vital.

Autotrophic Nutrition in Plants

• Photosynthesis is a mechanism that allows plants to manufacture their nourishment.

• Photosynthesis takes place in the chloroplast.

• The majority of food production takes place in leaves. The root absorbs water and nutrients from the soil and transports them to the leaves through vessels. Stomata, which are microscopic holes on leaves bordered by guard cells, allow carbon dioxide to access the leaves.

• Chlorophyll is a green pigment found in leaves that aids in the collection of energy from the sun for the leaves to prepare their meal. Photosynthesis is the process of food creation that occurs in the presence of sunshine. As a result, all living species rely on the sun as their principal source of energy.

• In the presence of sunshine, water and carbon dioxide are utilised to build carbohydrates and oxygen during photosynthesis. All living things get their sustenance via photosynthesis.
  

Essential Nutrients for Plants

Plants require particular elements or compounds known as plant vital nutrients to grow, develop, and produce at their optimum.

A plant lacking an important nutrient will not be able to complete its life cycle—the seed will not germinate; the plant will not be able to form adequate roots, stalks, leaves, or flowers; and it will not be able to generate seeds to make new plants. Frequently, the plant will perish.

Too much of a nutrient, on the other hand, can damage or even kill plants. Too much nitrogen, for example, might lead a plant to produce more leaves but less or no fruit. If the leaves are exposed to too much manganese, they will turn yellow and finally die. Furthermore, too much boron can kill a plant.

Conditions Required for Photosynthesis:

Photosynthesis is Broken Down into Several Steps:

• The process of absorbing energy from the sun.

• Light energy is converted into chemical energy.

• Water is broken down into oxygen and hydrogen through hydrolysis.

• Chemical energy is used to convert carbon dioxide to glucose.
  

Plants with Heterotrophic Nutrition

Some plants lack chlorophyll and rely on other plants for nourishment, which is known as the heterotrophic mode of feeding. Heterotrophic nutrition in plants is what these types of nutrition are termed, and parasites are what they are named.

Heterotrophic Plants

Different varieties of heterotrophic plants are listed below, which are mostly categorised depending on their style of nutrition:

• Parasitic

• Insectivorous

• Saprophytic

• Symbiotic
  

Parasitic Nutrition

Some heterotrophic plants rely on the sustenance of other plants and animals. Parasitic plants are those that feed on other plants. The parasite, on the other hand, does not help the host.

Example – Cuscuta, Cassytha, etc.

Conclusion

For the survival of plants, they also require 16 essential elements. Scientists have Derived Two Modes of Nutrition; Autotrophic and Heterotrophic. Plants synthesize their food by using minerals, carbon dioxide, water, and sunlight. These factors must be adequately supplied for growth and development.