We explain what anabolism is and its differences with catabolism. Also, importance, types of anabolism and examples.
What is anabolism?
Anabolism is the phase of metabolism in which complex biochemical structures are generated from simpler substances . In other words, the body’s chemical energy is invested to compose complex biomolecules from simple ones, using reducing power. It is an opposite and complementary process of catabolism .
The name of the term comes from the Greek ana (“upwards”) and ballein (“to throw”), since it implies the synthesis of more complex compounds from simpler ones, going “upwards” from the basic to the complicated. In order to do so, however, an additional energy input (endergonic reactions) is required.
Like catabolism, it occurs inside cells and is driven by the action of enzymes ( catalytic proteins ).
See also: Endothermic reactions
Differences between anabolism and catabolism
Catabolism converts complex molecules into simpler molecules.
Catabolism and anabolism are complementary, albeit opposite, processes . While catabolism breaks down macromolecules into simpler forms, releasing the chemical energy contained in their chemical bonds , anabolism consumes that released energy to form new bonds and new complex molecules , going in the opposite direction.
Thus, one consumes energy and the other releases it ; one goes from the basic to the complex and the other vice versa. When both catabolism and anabolism are in balance, the cell remains stable. But when it is necessary to grow or reproduce, anabolism predominates in them , to manufacture the additional biochemical pieces necessary to increase in size or complexity.
More in: Catabolism
Importance of anabolism
The growth of children is an example of anabolism.
Anabolism is a vital metabolic stage, not only to provide inputs for catabolism to break down and release chemical energy, but also to:
- The storage of energyin the chemical bonds of complex molecules (such as starch in plants , or glycogen and triglycerides in animals).
- The elaboration of components of cellsand tissues, thus allowing the increase in muscle mass and the growth of the organism.
- The manufacture of new cellsto replace old ones and replenish damaged tissues.
autotrophic anabolism
In autotrophic beings (those capable of synthesizing on their own the nutrients necessary to sustain their existence) anabolism generally involves the transition from inorganic molecules (such as water , carbon dioxide , etc.) to organic molecules of greater complexity and biochemical utility . This process can occur in two different ways:
- Photosynthesis. It is the metabolic process of plants and organisms endowed with chlorophyll, in which carbon dioxide (CO2) and water (H2O) are consumed to compose starch (sugar) molecules. This process gets its necessary energy from sunlight .
- This process occurs mainly in microscopic organisms such as bacteria and archaea, in whose habitat there is no usable sunlight, but other types of chemical substances in constant reaction, which are used to synthesize organic molecules from, for example, ammonia (NH3 ).
heterotrophic anabolism
The anabolism of heterotrophs transforms organic matter into parts of cells.
In heterotrophic beings (which require consuming the organic matter of other living beings to feed themselves), anabolism differs from autotrophism in that its simple compounds are organic in nature, that is, they are the result of the digestion and decomposition of food . . The energy necessary for this is obtained from ATP (Adenosine Triphosphate) produced during catabolism.
Examples of Anabolism
Anabolism can be exemplified in the growth phases of living beings : children that grow in weight and height, plants that put out new stems, animals that increase in size.
For an anabolic process to occur, new cells are required to make new tissue. This is obtained by increasing the amount of biochemical material and biochemical energy available to the body. In that case, plants require sunlight, carbon dioxide in the air , and water, while animals and humans need food and oxygen.