“The Living World”  Biology-11th

Chapter-1st

The  

living  

world  

is  

rich  

in  

variety.  

Millions  

of  

plants  

and  

animals  

have

been   

identified   

and   

described   

but   

a   

large   

number   

still   

remains

unknown.

The  

very  

range  

of  

organisms  

in  

terms  

of  

size,  

colour,  

habitat,

physiological  

and  

morphological  

features  

make  

us  

seek  

the  

defining

characteristics  

of  

living  

organisms.  

In  

order  

to  

facilitate  

the  

study  

of

kinds  

and  

diversity  

of  

organisms,  

biologists  

have  

evolved  

certain  

rules

and   

principles   

for   

identification,   

nomenclature   

and   

classification   

of

organisms.  

The  

branch  

of  

knowledge  

dealing  

with  

these  

aspects  

is

referred  

to  

as  

taxonomy.  

The  

taxonomic  

studies  

of  

various  

species  

of

plants  

and  

animals  

are  

useful  

in  

agriculture,  

forestry,  

industry  

and  

in

general  

for  

knowing  

our  

bio-resources  

and  

their  

diversity.

The  

basics  

of

taxonomy  

like  

identification,  

naming  

and  

classification  

of  

organisms  

are

universally    

evolved    

under    

international    

codes.    

Based    

on    

the

resemblances  

and  

distinct  

differences,  

each  

organism  

is  

identified  

and

assigned  

a  

correct  

scientific/biological  

name  

comprising  

two  

words  

as

per     

the     

binomial     

system     

of     

nomenclature.     

An     

organism

represents/occupies  

a  

place  

or  

position  

in  

the  

system  

of  

classification.

There   

are   

many   

categories/ranks   

and   

are   

generally   

referred   

to   

as

taxonomic  

categories  

or  

taxa.

All  

the  

categories  

constitute  

a  

taxonomic

hierarchy.

Taxonomists  

have  

developed  

a  

variety  

of  

taxonomic  

aids  

to  

facilitate

identification,  

naming  

and  

classification  

of  

organisms.  

These  

studies

are  

carried  

out  

from  

the  

actual  

specimens  

which  

are  

collected  

from  

the

field  

and  

preserved  

as  

referrals  

in  

the  

form  

of  

herbaria,  

museums  

and

in    

botanical    

gardens    

and    

zoological    

parks.    

It    

requires    

special

techniques  

for  

collection  

and  

preservation  

of  

specimens  

in  

herbaria

and   

museums.   

Live   

specimens,   

on   

the   

other   

hand,   

of   

plants   

and

animals,   

are   

found   

in   

botanical   

gardens   

or   

in   

zoological   

parks.

Taxonomists    

also    

prepare    

and    

disseminate    

information    

through

manuals  

and  

monographs  

for  

further  

taxonomic  

studies.  

Taxonomic

keys are tools that help in identification based on characteristics.