LIFE (ජීවය)

This is our first lesson about biology.So I think it should be an easy one for all.

Actually what is life?How can you define it?

Well,nobody has done it successfully upto date. But, we can surely distinguish living things from non-living things based on the following attributes which are only shown by living things(organisms)

1.Adaptation (අනුවර්තනය)
The structural & functional alterations occured in living beings in order to obtain energy & matter efficiently from the environment to maintain life & reproduce.

2.Order & Organization (ක්රමවත් බව සහ සංවිධානය)
The biological structure of a living organism is well organized.For example,we can have a look at the human body.First, the cells are organized into tissues.Then the tissues are organized into organs.Then the organs into systems & systems into the complex human body are organized.

3.Metabolism (පරිවඃත්තීය ක්රියා)
This is the biochemical reactions happen inside living organisms.Basically, they can be devided into
I )catabolism (අපවඃත්තීය), which is the breaking up process of large complex molecules into small simple molecules (ex: cellular respiration)&
II)anabolism (සංවඃත්තීය), which is the building process of large complex molecules from small simple molecules(ex: photosynthesis).

4.Responsiveness (ප්රතිචාර දැක්වීම)
Living organisms respond to the changes in external & internal environments.

5.Reproduction (ප්රජනනය)
Only living things can generate an offspring of their own kind.

6.Movement (චලනය)

7.Heridity (ආවේණිය)
Transmission of biological features into offspring with generations.

8.Evolution (පරිණාමය)
Accumulation of hereditory(genetical) changes with time.

9.Growth & Development (වර්ධනය සහ විකසනය)
Growth is the enlargement of the body whereas development is the generation of new body parts.

10.Death (මරණය)