Definition of Life – a biophysical approach
Probably the best place to start our discussion on the Earth’s biogeography would be to answer the next question: What is the definition of life? While the answer to this question may seem simple, scientists have actually spent a lot of time pondering this issue. In fact, many scientists indicate that we still don’t have a clear definitive response to this question. Part of this problem relates to the existence of viruses along with other forms of micro organisms. Some scientists outline viruses as extremely complex organic elements, while others suggest they’re the simplest sort of life.
In a recent issue from the journal Science (03, 22, 2002), molecular biologist Daniel E. Koshland Jr. was asked to post a special article where he would attempt to define life. In this document, he suggested that something may be considered “alive” in the event that it meets the subsequent seven conditions.
- Living things will need to have a program to create copies of them selves from generation to generation. This program would describe the two parts that define the organisms and also the processes that occur between various parts. These processes are obviously the metabolic reactions that occur in a living thing making it function over a time period. In most living systems, the program of life is encoded inside DNA.
- Life adapts and also evolves in phase with external changes within the environment. This process is directly attached to life’s program by means of mutation and organic selection. This condition allows life-forms to become optimized for gradual changes inside the environment.
- (Organisms tend to get highly organized, complex, and most essentially have compartmentalized structures. Chemicals found inside their bodies are synthesized by means of metabolic processes into structures which have specific purposes. Cells and their own various organelles are samples of such structures. Cells are also the fundamental functioning unit associated with life. In multi-cellular creatures, cells are frequently organized into organs to produce higher levels of complexity and functionality.
- (Living things are able to take energy using their environment and modify it from one form to a different form. This energy is generally used to aid their growth as well as reproduction. We call the procedure that allows this facilitation metabolism.
- Organisms have regeneration devices that replace elements of themselves that are generally subject to deterioration. This regeneration may be partial or it could involve the complete replacement of their entire organism. Complete replacement is essential because partial substitutions cannot stop the actual unavoidable decline within the functioning state in the entire living system as time passes. In other words, all organisms degrade in a final non-functioning condition we call dying.
- Living creatures react to environmental stimuli by way of feedback mechanisms. Cues from environmental surroundings can cause creatures to react via behavior, metabolism, and physiological adjustment. Further, responses to stimuli generally act to improve a creature’s probability for day-to-day survival.
- Organisms are capable of maintaining numerous metabolic reactions even in one instance in a time period. Living things also keep all these reactions separated one from another. This and all of the above make in biophysical terms the definition of life.