Characteristics of living beings
Biology / / July 04, 2021
Living beings are made up of a set of molecules that make up their structure, in an organized way and complex, having the ability to make exchanges of matter and energy, to perform its functions vital.
Living beings are made up of different elements, being hydrogen, oxygen, nitrogen, carbon, iron, calcium, and others, its main components, all in different forms within its structure.
Being among these elements, carbon, hydrogen, oxygen and nitrogen, the elements of which the bio-molecules that form living matter are formed.
Living beings are beings that have an intrinsic complexity, which is defined by the aspects common to all of them, which differentiates them from inert minerals.
Living beings are made up of cells, either one or several, which are grouped together, and perform different functions.
In single-celled organisms, several different parts of the cell are responsible for vital functions, such as feeding, reproduction, and the disposal of unnecessary products.
In multicellular organisms, these basic functions are carried out by groups of specialized cells, which form tissues, organs and specialized organic systems in different functions.
Main characteristics in living beings:
Living beings have complex functions that are performed by cells, whether these are unicellular or multicellular living beings. Cells perform different processes in a coordinated and organized way, the different specific functions they perform within the living being to which they belong.
In unicellular living beings, the cell that makes up this type of life form fulfills the basic functions necessary for life, such as the metabolism of substances for their feeding and obtaining energy, reproduction, disposal of unnecessary substances, movement and increase.
In multicellular beings, these aspects are distributed among different cells, which form tissues and organs. each cell group specializing in one or more specific functions, such as feeding, reproduction or increase.
Another aspect of living things is metabolism. Living beings need energy and elements for their development, which they assimilate through internal biochemical processes. To carry out this function, they transform the materials through synthesis and chemical degradation processes, to obtain the substances they need. for the continuation of vital processes, growth, and tissue repair for the continuation of life, these processes are called as metabolism.
Living beings the ability to grow; In order to grow, they need the necessary elements for the synthesis of products for the creation of new living matter, with which to build and renew the elements of which they are constituted.
In unicellular organisms, growth occurs through an increase in cell mass, after the synthesis of the elements that the body needs for this purpose.
In multicellular organisms, growth is carried out by increasing the number of cells in the organisms and the creation or replacement of new tissues where they are created. new cells that replace cells that no longer fulfill their functions, replacing them with cells or groups of similar cells to carry out their biological functions. This is the case of the growth of animal organs and tissues, which is carried out by replacing cells that no longer function, by new cells, old cells being discarded and parts of their elements reabsorbed, as in the case of water from the cell cytoplasm, which is reuse.
This differs from the apparent growth of minerals, where the apparent growth is due to the accumulation of mineral substances in a given place, by action of physical phenomena, as in the case of stalagmites and stalactites that apparently grow when the mineral accumulates through the filtration.
Living beings are distinguished by reproduction, which is the ability to generate other individuals of the same differences as the organism that produces them. This can be asexual, or sexual, being asexual reproduction, aspects mainly of unicellular organisms or simple multicellular organisms. Being carried out through the division of a primary cell, in unicellular organisms, and from the division of several cells in simple multicellular organisms.
Sexual reproduction occurs in most multicellular organisms, both plant and animal, taking place through the union of two individuals who each contribute a portion of the material and information (Genes), for the creation of a new individual with characteristics similar to those of the procreators.
Another faculty of living beings is adaptation. Living beings have the ability to adapt to the environment in which they live, to be able to face the changes that occur in the environment in which they live.
This adaptation is evolutionary, with which through several generations they adapt to a given environment, creating defenses against the environment, as in The case of some animals that live in cold environments, and adapt their skin to contain more fat and create a dense coat, with which to survive when cold. Another example of adaptation to the environment, which occurs with evolution, is the change of tonalities in the feathers of birds, or the skin of animals, to be able to camouflage and hide from predators, adapting to the environment in which they live.
Living things are distinguished by irritability, or response to external stimuli. Living beings have the peculiarity of responding to stimuli caused by physical and chemical changes that act on them, react to stimuli such as light, pressure, temperature and / or composition of the soil, water, air, etc.
This peculiarity is more evident in animals than in plants, the reactions to stimuli of various kinds being evident, in Multicellular and complex animals, as well as in unicellular ones, for example bacteria react when stimulated by light, or animals to noise. Although there are vegetables that have a more noticeable sensitivity to stimuli, which can be observed in some plants. This is the case of sunflowers, which by stimulating sunlight, rotate to continue to maintain the light rays necessary for their metabolism.
In animals the stimuli are more noticeable, being easy to identify the sensitivity towards stimuli such as noise, light or movement. This can be observed, for example, by stimulating bacteria by light, or by temperature changes to any animal.
Another important aspect of living is homeostasis, with which they maintain the constancy of the internal environment of the organism, water, temperature, electrolyte balance, etc. This aspect is easy to observe in animal cells.
In the case of viruses, there is confusion in their classification; They are classified differently from living beings, because they have some qualities of living beings but not all.
Viruses have DNA or RNA, which is the basic information that living beings have for their reproduction and the specification of the functions that their parts will perform. But viruses do not have their own metabolism, they use the metabolism of a living being when they parasitize an organism, taking the metabolism of the cell they infect to perform the metabolic functions necessary for the reproduction of more virus. Therefore viruses do not meet the requirement of having a metabolism with which to obtain energy from organic or other substances such as plants or animals. They have no excretion mechanism for wastes that could be produced through metabolism.
Viruses have the ability to evolve through mutations, but this quality is not enough to be counted among living beings.
Although viruses have the ability to multiply, they do not do it by themselves, they need to introduce the information of their DNA or RNA, in the infected cell so that it is the one that performs the functions that will lead to the multiplication of the virus, through the replication of the genetic information of the virus in the cell, being the cell the one that carries out the reproduction processes properly sayings.
Viruses lack their own movement, being moved by the environment in which they are, such as water, or dust.