Biologists study life to the extent to which they can uncover, unearth and investigate unseen, latent, and concealed life forms that are still many in number, these crawling and under-the-water creatures.
And in an experimental sense, many biologists are guided by ethics in researching life forms. This is to protect and inhibit another biologist from killing thousands of these living organisms and prevent them from becoming extinct.
Remember that biologists or any other scientists study because of knowledge and to contribute to the scientific world of making the ecosystem including us into a much better and cultured place and not the opposite. Hence, there are non-experimental and experimental approaches that are all subject to ethics. In exploring life forms, it is quite unlimited but studying life forms in an experimental sense
Biologists study life at eight levels:
1. Molecular level: Biologists study all organic and inorganic molecules like proteins, carbohydrates, fats, etc. All of these molecules are important for sustaining life.
2. Cellular level: A cell is a basic unit of existence. The study of life at the cellular level involves all the metabolic processes occurring inside the cell, including the formation (anabolism) and breakdown (catabolism) of molecules.
3. Tissue level: Tissues are made of cells that group together for a common function. The tissue level of organization is found in the Coelenterata phylum of the animal kingdom. For example, blood is a tissue that carries out many vital functions of the human body. Biologists that focus on this level are called histologists.
4. Organ level: An organ is formed when tissues work together on a bigger level to perform a certain task in a body. An example of an organ is the brain, which carries out the function of coordination in our body. At this level, the study is known as anatomy.
5. Organ system level: Many organs work together to form a system. The human body contains 11 such systems, including the digestive system, respiratory system and endocrine system. These biologists are known as physiologists.
6. Organism level: Every independent living creature is an organism. These can be unicellular or multicellular.
7. Population-level: The broadest study of life (in one area alone) can be done at the population level. Such a study includes the study of mortality rate, birth rate, disease occurrence, etc., in a group of organisms of the same species that inhabit a particular area. A population further contains community (all species in an area) and ecosystem (all communities and the environment of an area) levels that can be studied.
Note that until the organism and population levels, only the living component of life is studied. The later levels study the non-living part of Earth, which is responsible for life as well.
8. Biosphere level: The biosphere is the sum of all ecosystems on Earth and is the broadest area where life can be studied. The biosphere contains abiotic and biotic components; every component that is present in the explored world is part of the biosphere. It includes rocks, oceans, plants, animals; everything. The specialized persons who work at this level include meteorologists and geologists.
