Properties of Life

Prepared by: Reo Paolo M.Uri

Biology is the study of life. But what does it mean to be alive? What are the properties that define a living organism? This is not simple or question as it seems because some of the most obvious properties of living organism are also properties of many non-living things. For example, complexity (a computer is complex), movement (clouds move in the sky), and response to stimulation ( a soup bubble pop if you touch it). To appreciate why these three properties, so common among living things, do not help us to define life, imagine a mushroom standing next to a television: the television seems more complex than the mushroom, the picture on the television screen is moving white continue to just stands there, and the television responds to a remote control device unite the mushroom continue to just stand here- yet it is the mushroom that is alive.

All living things share five basic properties, passed down over millions of years from the first organisms to evolve on earth: cellular organization, metabolism, homeostasis, growth and reproduction, and heredity.

1. Cellular organization. All living are compose of one or more cells. A cell is a tiny compartment with a thin covering called a membrane. Some cells have simple interiors, while other are complexilly, organized, but all are able to grow and reproduce. Many organisms possess only a single cell, like the blue-colored poraxemia having dinner in your bony contains about 100 trillion cells-that's how many centimeters long a string would be wrapped around the world 1,000 times?

2. Metabolism. All living things use energy. Moving, growing thinking everything you do requires energy. Where does all this energy come from? It is captured from sunlight by plants and algae through photosynthesis. To get the energy that powers our lives, we extract it from plants or form plant eating animals. That's what the kingfisher is doing eating a fish that ate algae. The transfer of energy from one form of another in cells is an example of metabolism. All organisms require energy to grow, and all organisms transfer this energy this energy from one place to another within cells using special energy-carrying molecules called ATP molecules.

3. Homeostasis. All living things maintain stable internal condition so that their complex processes can be better coordinated. While the environment of ten varies a lot, organisms act to keep their interior conditions relatively constant a processes  called homeostasis. Your body acts to maintain an internal temperature of 37C ( 98.6 F), however hot or cold the water might be.

4. Growth and reproduction. All living things grow and reproduce. Bacteria increase in size and simply split in two, as often as every 15 minutes, while more complex organisms grow by increasing the number of cells and reproduce sexually (some, like the bristlecone pine of California, have reproduced after 4600 years ago).

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