what is the definition of life?

Answer 1

A conventional definition

Although there is no universal agreement on the definition of life, scientists generally accept that the biological manifestation of life exhibits the following phenomena:

1. Homeostasis: Regulation of the internal environment to maintain a constant state; for example, sweating to cool off.
2. Organization: Being composed of one or more cells, which are the basic units of life.
3. Metabolism: Production of energy by converting nonliving material into cellular components (synthesis) and decomposing organic matter (catalysis). Living things require energy to maintain internal organization (homeostasis) and to produce the other phenomena associated with life.
4. Growth: Maintenance of a higher rate of synthesis than catalysis. A growing organism increases in size in all of its parts, rather than simply accumulating matter. The particular species begins to multiply and expand as the evolution continues to flourish.
5. Adaptation: The ability to change over a period of time in response to the environment. This ability is fundamental to the process of evolution and is determined by the organism's heredity as well as the composition of metabolized substances, and external factors present.
6. Response to stimuli: A response can take many forms, from the contraction of a unicellular organism when touched to complex reactions involving all the senses of higher animals. A response is often expressed by motion, for example, the leaves of a plant turning toward the sun or an animal chasing its prey.
7. Reproduction: The ability to produce new organisms. Reproduction can be the division of one cell to form two new cells. Usually the term is applied to the production of a new individual (either asexually, from a single parent organism, or sexually, from at least two differing parent organisms), although strictly speaking it also describes the production of new cells in the process of growth.

Answer 2

"One definition of life, albeit not a particularly useful one, might run as follows: life is that property a being will lose as a result of falling out of a cold and mysterious cave fourteen miles above ground level. This is not a particularly useful definition because a) it could equally refer to the subject's spectacles, if he happened to be wearing them, and b) because it fails to take into account the possibility that the subject might fall onto the back of an extremely large passing bird. The first of these is due to sloppy thinking, but the second is excusable as the mere idea is quite clearly utterly ludicrous."

Answer 3

In my book, life is consciousness. I don't consider plants to be life forms. They're machines. Consciousness requires a complex centralized nervous system that plants just don't have.

I know the bilogical definitions of life. I just think that consciousness is a more meaningful definition.

Answer 4

Books, light bulbs, stars have a life-span...they dont breathe in and out or excrete and eat.......

From the moment something is concieved it gets older and nothing lives forever.... isnt the definition of life the process of dying?

Answer 5

Life forms 'make an effort' to remain alive and change. Chemical reactions, like fire, resemble life but cannot change. I remember someone wrote that-- I think it was Issac Asimov: scientist-author. I will research this. Get back to me.

Answer 6

MERRING is one definition.

Movement - plants do move a little!
Excretion - Getting rid of waste products
Respiration (not just breathing, but burning fuel & use of energy)
Reproduction
Irritability - reacts to stimuli
Nutrition - feeding
Growth

A virus is a borderline case.

Answer 7

Life is a game, play it.

Answer 8

B O O !


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Answer 9

Life is hAVING A GOOD TIME AND DOIN WHAT EVER U WANT. It is about gettin married and hvin children.

Answer 10

FUN
F-is for friends who do stuff together
U- is for you and me
N-is for anywhere at anytime at all down here in the deep blue sea