Concept of metabolism and living state

Thousands of organic chemicals can be found in living species, whether they be bacteria, protozoa, plants, or animals. These substances or biomolecules exist at specific concentrations (mols/cell, mols/litre, and so on). The discovery that all biomolecules have a turnover was one of the most significant discoveries ever made. This means they're continually changing into and out of different biomolecules. Chemical reactions occur frequently in living organisms, breaking and making this possible. Metabolism refers to the sum of all these chemical events. The change of biomolecules occurs in each of the metabolic processes.

Removal of carbon di oxide from amino acids, resulting in an amine, removal of amino group in a nucleotide base, hydrolysis of a glycosidic bond in a disaccharide, and so on are some examples of metabolic transformations. There are tens of thousands of examples like this. The majority of these metabolic events are always related to other reactions and do not occur in isolation. In other words, metabolites are changed into one another through metabolic pathways, which are a set of related reactions. These metabolic pathways are comparable to city traffic in terms of complexity. There are two types of pathways: linear and circular. There are traffic crossroads where these paths cross one other.Like car traffic, the flow of metabolites through the metabolic pathway has a set rate and direction. The dynamic state of bodily constituents refers to this metabolite flux. What matters most is that this interconnected metabolic traffic runs smoothly and without a single reported hiccup under normal circumstances. Every chemical reaction in these metabolic pathways is a catalysed reaction, which is another distinguishing trait. In biological systems, there is no metabolic conversion that is not catalysed. Even the physical process of CO2 dissolving in water is a catalysed reaction in biological systems. Proteins are also catalysts that speed up the tempo of a metabolic conversation. Enzymes are the name given to these catalytic proteins.

Metabolic basis for living

Metabolic pathways can either lead to a more complex structure from a simpler structure (e.g., acetic acid becomes cholesterol) or a simpler structure from a complex structure (e.g., acetic acid becomes cholesterol) (for example, glucose becomes lactic acid in our skeletal muscle). The former are referred to as biosynthetic or anabolic pathways. The latter are referred to as catabolic pathways since they involve degradation. Anabolic pathways, use a lot of energy. Energy is required to assemble a protein from amino acids. Catabolic pathways, on the other hand, result in the release of energy. When glucose is metabolized to lactic acid in skeletal muscles, for example, energy is released. Glycolysis is a metabolic mechanism that takes glucose and converts it to lactic acid in ten stages.

Living organisms have figured out how to capture the energy released during breakdown and store it as chemical bonds. This bond energy is used as needed for biosynthetic, osmotic, and mechanical tasks that we do. The bond energy in a molecule called adenosine triphosphate is the most essential kind of energy currency in living systems (ATP).

The living state

Tens and thousands of chemical compounds in a living organism, otherwise called metabolites, or biomolecules, are present at concentrations characteristic of each of them. For example, the blood concentration of glucose in a normal healthy individual is 4.5-5.0 mM. The most important fact of biological systems is that all living organisms exist in a steady-state characterized by concentrations of each of these biomolecules. These biomolecules are in metabolic flux. Any chemical or physical process moves spontaneously to equilibrium. The steady state is a non-equilibrium state. One should remember from physics that systems at equilibrium cannot perform work. As living organisms work continuously, they cannot afford to reach equilibrium.

Thus, to be able to conduct work, the living state is a non-equilibrium steady-state; the living process is a constant endeavour to avoid slipping into equilibrium. This is accomplished by the use of energy. Metabolism is the process by which energy is produced. As a result, the terms "living state" and "metabolism" are interchangeable. There can be no living condition without metabolism.