Question

What are the reaction mechanisms for photosynthesis and a plant taking in and using the following nutrients: nitrogen, phosphorus, potassium?

Answer 1

Photosynthesis is an oxidation reduction process in which water is oxidized and carbon dioxide is reduced to carbohydrate.

Blackmann (1905) pointed out that the process of photosynthesis consists of two phases:

(1) Light reaction or Light phase or Light-dependent phase or Photochemical phase

(2) Dark reaction or Dark phase or Light independent phase or Biochemical phase.

During light reaction, oxygen is evolved and assimilatory power (ATP and NADPH2) are formed. During dark reaction assimilatory power is utilized to synthesize glucose.

(i) Oxygenic photosynthesis (with evolution of O2) takes place in green eukaryotes and cyanobacteria (blue-green algae).

(ii) An oxygenic photosynthesis (without the evolution of O2) takes place in photosynthetic bacteria.

or other oxidised compounds or some other inorganic compounds.

Nitrogen is a paramount element for plants since it is a core component of many plant structures and for both their internal and external metabolic processes. Plants are required to manufacture the complex molecules through metabolism activities to survive by use of minerals from the soil that contain nitrogen such as nitrate ions.The wellness of plant parts (leaves, roots, trunks e.t.c) depends on the availability of essential nutrients like nitrogen to enhance the plant's biological processes including growth, absorption, transportation, and excretion.

Nitrogen (N) in a way could be termed "a backbone" of plants going by what it does in plants. Of all the essential nutrients, Nitrogen is required by plants in large amounts since it plays important functions and can be the limiting factor in plant production and proper crop development. Here is a look at Nitrogen's functions in plants:

- Nitrogen is an essential element of all the amino acids in plant structures which are the building blocks of plant proteins, important in the growth and development of vital plant tissues and cells like the cell membranes and chlorophyll.

- Nitrogen is a component of nucleic acid that forms DNA a genetic material significant in the transfer of certain crop traits and characteristics that aid in plant survival. It also helps hold the genetic code in the plant nucleus.

- Chlorophyll being an organelle essential for carbohydrate formation by photosynthesis and a substance that gives the plant their green color, nitrogen is a component in it that aids in enhancing these features.

- Nitrogen is essential in plant processes such as photosynthesis. Thus, plants with sufficient nitrogen will experience high rates of photosynthesis and typically exhibit vigorous plant growth and development.

Phosphorus (P) is part of the nuclei acid structure of plants which is responsible for the regulation of protein synthesis. Phosphorus plays a major role in the growth of new tissue and division of cells. Plants perform complex energy transmissions, a function that requires phosphorus. One of the benefits of phosphorus in plants is proper development of the roots and hastening of maturity.

Phosphorus is responsible for a number of functions in plants which underlines its importance to the plants in your garden. The growth of plants is boosted by phosphorous whose lack leads to weak plants that fail to produce as expected. Plants require capturing the rays of the sun during photosynthesis. The following are the main functions performed by phosphorus in the life of plants:

- Stimulates root development necessary for the plant to get nutrients from the soil. The roots are also necessary for the support of the plant. When the roots are well developed, they are able to penetrate the ground and gather all the nutrients required by the plant for development.

- Boosts the development of the plant. Plants require nutrition for their development. The nutrition is processed in the leaves and then stored or transferred to other parts of the plants. Phosphorus is required for photosynthesis and also in the storage and transportation of the nutrients throughout the plant.

- Plants are expected to produce fruit after a given time if all the circumstances are right. Phosphorous is responsible for crop maturity at the right time. Plants that lack phosphorous take time to mature and when they do, the fruits or seeds they bear are few and poor in quality.

- Legumes help in fixing nitrogen in the soil through their roots. This function cannot be carried out well without phosphorous which boost the development of the roots.

- The substances required for the formation and development of genes cannot perform well without the availability of phosphorous. The transfer of the genes from one generation to the next is only possible when phosphorous is available.

- Plants that have access to enough phosphorous have the ability to resist diseases because all their parts are well developed and grow quickly. Plants grown using hydroponics are supplied with enough phosphorous to ensure they grow well.

Potassium is an indispensable constituent for the correct development of plants. It is important in photosynthesis, in the regulation of plants responses to light through opening and closing of stomata. Potassium is also important in the biochemical reactions in plants. Basically, potassium (K) is responsible for many other vital processes such as water and nutrient transportation, protein, and starch synthesis.

Potassium (K) essentially plays a major role in plant physiological processes. Therefore, it is required in large amounts for proper growth and reproduction in plants. It is considered vital after nitrogen as far as nutrients needed by plants is concerned. It is also termed "the quality nutrient" for its contributing factor in a number of biological and chemical processes in plants. Here is why Potassium is important in plants:

- Potassium regulates the opening and closing of stomata thus regulating the uptake of CO2 thus enhancing photosynthesis.

- It triggers activation of important biochemical enzymes for the generation of Adenosine Triphosphate (ATP). ATP provides energy for other chemical and physiological processes such as excretion of waste materials in plants.

- It plays a role in osmoregulation of water and other salts in plant tissues and cells.

- Potassium also facilitates protein and starch synthesis in plants.

- It activates enzymes responsible for specific functions.