Adaptation of LivingThings

Certain animals andplants develop characteristics that help them cope with their environmentbetter than others of their kind.This natural biological process is called

adaptation.Among thesuperior characteristics developed through adaptationare those that may help ingetting food or shelter,in providing protection,and in producing and

protecting theyoung.That results in the evolution of more and more organisms（微生物）that are better fitted to theirenvironments.

Each living thing isadapted to its way of life in a general way,but each is adapted especially toits own distinct class.A plant,for example,depends upon its roots to fix itself

firmly and to absorbwater and inorganic（无机的）chemicals.Itdepends upon its green leaves for using the sun's energy to make food frominorganic chemicals.These are

generaladaptations,common to most plants.In addition,there are special adaptationsthat only certain kinds of plants have.

Many animals haveadaptations that help them escape from their enemies.Some insects are hidden bytheir body color or shape,and many look like a leaf or a little branch.The

coats of deer arecolored to mix with the surroundings.Many animals have the ability to remaincompletely still when an enemy is near.

Organisms have agreat variety of ways of adapting.They may adapt.in theirstructure,function,and genetics;in their development and production of theyoung;and in other

respects.An organismmay create its own environment,as do warm-blooded mammals（哺乳动物）,which have the ability to adjustbody heat exactly to maintain their ideal

temperature despitechanging weather.Usually adaptations are an advantage,but sometimes an organismis so well adapted to a particular environment that,if conditions

change,it finds itdifficult or impossible to readapt to the new conditions.

Some plants andanimals develop superior characteristics so that they may______.

A.help others oftheir kind get food,shelter and other things needed

B.survive even inextremely severe conditions

C.become betteradapted to the environments than others of their kind

D.result in theevolution and production of more intelligent organisms