Every living organism that lives on our planet is an open system. Its functioning depends on how substances necessary for vital activity come from the external environment. Information on how the first living organisms ate , as well as on the types of nutrition you will find below. There are several types of implementation of this process.
Nutrition of living organisms
In order for an elementary biological system to exist and function, it needs certain elements to build a body. The process in which energy and substances are consumed is commonly called nutrition.
Types of food
Scientists distinguish the following types of nutrition of living organisms - heterotrophic and autotrophic. At the same time, an autotroph is an organism for which carbon dioxide directly serves as a carbon source. These include some types of bacteria, as well as plants. Such an organism can create organic substances by consuming inorganic substances.
Autotrophs, in turn, are usually divided into chemotrophs and photoautotrophs. The latter are organisms that use the energy of light to carry out a process called biosynthesis. The first option involves the use of the energy of oxidative reactions for compounds of inorganic origin.
Heterotrophs are called living organisms, for which substances of organic origin in the finished form are needed. It is customary to include many types of bacteria, all fungi and animals. These are all mammals in particular.
Depending on the method of obtaining useful substances, scientists also divide heterotrophs into two types. This is the phagotroph organism, which swallows solid food, as well as the osmotroph, which absorbs useful components in the form of a solution from the cell walls.
Among heterotrophs, there is a type of organism called saprotroph. There is also another, which should be called a biotroph. For the latter, the food source is a living organism. If we talk about saprotrophs, then they use nutrients of organic origin from the dead or excrement of living creatures (for animals) to feed them. Some species of fungi, bacteria, plants, animals are included here. There are also mixotroph organisms that feed on both finished organic substances and are able to create from inorganic ones.
How did the first living organisms eat: the opinion of scientists
Scientists at the present stage have not yet come to a single conclusion about how the first creatures lived on the planet. This also applies to how the first living organisms ate. But almost all scientists recognize the fact that they used substances of inorganic origin as food as a result of abiogenic reactions. It could be the action of the rays of the sun, the discharge of a thunderstorm, or the heat generated by geysers, etc. Thus, the way the first living organisms ate, is now the subject of discussion among scientists.