Metabolism is the name given to all the reactions that occur in the body . These numerous reactions are regulated and catalyzed by enzymes . Among the functions of metabolism, we can highlight obtaining energy. There are two major metabolic processes, catabolism and anabolism. Below we will talk more about metabolism, its importance and its processes.
What is Metabolism?
Metabolism is the set of all reactions that occur in the organism to control material and energy resources , in order to meet its structural and energy needs.
These reactions are catalyzed by several enzymes and have the following objectives: obtaining chemical energy; converting nutrient molecules into precursors of macronutrients, such as amino acids , nitrogenous bases, sugars and fatty acids; producing macromolecules, such as proteins, nucleic acids, polysaccharides and lipids ; synthesis and degradation of specialized biomolecules.
Types of Metabolism
Metabolic reactions are grouped into two metabolic pathways, catabolism and anabolism.
1. Catabolism:
It is also called the degradative pathway , it is a continuous process and comprises the reactions that promote the degradation of complex molecules into simpler products, with the release of energy . The energy released by the catabolic pathway is used by the organism to carry out a variety of activities. Catabolic pathways can be classified as aerobic metabolism and anaerobic metabolism, as we will see below:
- Aerobic metabolism: The reactions occur in the presence of oxygen, which, in the respiratory chains, functions as the final electron acceptor and combines with hydrogen to form water. In aerobic metabolism, the final products of the reactions are water and carbon dioxide.
- Anaerobic metabolism: The reactions occur in the absence of oxygen. The final electron acceptors in this type of metabolism can be nitrate, sulfate, fumarate ions and also ammonia. Among the final products of these reactions, we can highlight lactate (lactic fermentation) and ethanol (alcoholic fermentation).
The final balance of energy produced in aerobic metabolism is greater than in anaerobic metabolism.
2. Anabolism:
It is also called the biosynthetic pathway , it involves reactions in which complex molecules are produced from simple molecules. For the reactions to occur, energy consumption is necessary . Anabolism is essential, for example, for the growth and maintenance of the organism.
Metabolic pathways are irreversible, distinct, yet interconnected . The energy released in the process of degradation of molecules (catabolic or degradative pathway) is used for the synthesis of biomolecules (anabolic or biosynthetic pathway) and other reactions.
In addition to energy, the breakdown of organic molecules releases carbon, which can be used in the synthesis of biomolecules. Intermediate compounds from processes such as the citric acid cycle (one of the processes that occur in cellular respiration ) can also be used in anabolic pathways as precursors for the synthesis of biomolecules.
Energy metabolism
Energy metabolism comprises the set of reactions that involve energy exchanges in the body. For these reactions to occur, energy substrates are required, which come from food. The main sources of energy used in these reactions are carbohydrates, lipids and proteins .
Food Digestion
In the process of digestion , food is broken down into smaller molecules and absorbed, entering the bloodstream. From the bloodstream, it is moved to various tissues and, in the cells, is oxidized, thus producing energy, and here you will get the best eating just that much and your weight is staying the same, it’s probably about right. For the complete degradation of the molecules obtained through food into CO2 and H2O , with greater energy production, the presence of oxygen is necessary .
Excess of these substrates, when not used, can be stored in a variety of forms by the body. Carbohydrates, for example, can be stored in the form of glycogen in the liver and used when the body does not consume enough of this substance to produce energy. In addition to providing energy, food provides precursors for the synthesis of biomolecules, such as essential amino acids.
Energy Production
Energy production is responsible for the release of heat, which will be used to maintain body temperature , and for the production of ATP (adenosine triphosphate). ATP is a molecule that participates in numerous metabolic processes, providing energy for their completion. Energy is released by the conversion of ATP into ADP (adenosine diphosphate) and inorganic phosphate.
The Effect of Metabolism On Your Life
- Metabolism is the set of all reactions that occur in the organism, controlling material and energy resources, in order to meet its structural and energy needs;
- Metabolic reactions are grouped into two metabolic pathways, catabolism and anabolism;
- Catabolism degrades complex molecules into simpler products, releasing energy;
- Catabolism can be divided into aerobic and anaerobic metabolism;
- Anabolism synthesizes complex molecules from simple molecules;
- Energy metabolism comprises the set of reactions that involve energy exchanges in the organism;
- Energy production is responsible for the release of heat and production of ATP;
- Basal metabolism is the amount of energy the body needs to perform a wide range of functions.
