Model organisms are organisms used in the study of genetic fundamental processes, serving as models for certain species and being studied by a community of scientists. One of their main characteristics is that they own some features that make them easy to be used in genetic experiments and can be breed in laboratories. Using them, there can be obtained information about species that cannot be studied directly (like humans). They have a simple structure and they are used to study basic phenomena in biology, which is hard to be observed in advanced organisms. Each of them has their own advantages and disadvantages, which make the researchers choose one or another depending on the purpose their study rely on.
There are some criteria used in order to select the model organisms from the living organisms. They might have short life cycles and fast development, so the transformations can be easy observed on certain generations. They also should have a small size as an adult, which makes them easy to be raised in laboratories considering space and budget limitations. Another criterion is tractability, meaning the property of being easy to manipulate them. Usually, scientists work with different organisms, for making their findings more general and observing differences between them. They also use these model organisms as surrogates, by taking the experiments in a more favorable environment than the one in the studied system.
The observations of a particular phenomenon from biological studies of this species may be at least partially valid for the other species. Model organisms make possible to produce more simply studies that are difficult or impossible for technical or ethical reasons. One of the most important considerations for using an organism as a model system is its relevance to humans.
As an example, the mouse model system is used in the study of mammals, being the closest that can be used in the study of human diseases, because of its resemblance with the human genome. Even if there are differences between mice and humans, their actual biology is very similar to the one in the humans, and that’s why the human diseases are consistent in the mouse. Techniques for producing transgenic mice are well...