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SUBJECT-CHEMISTRY


                                                CHAPTER-BIOMOLECULES.

                      Carbohydrates: they are a class of compounds which include polyhydroxy aldehydes
                        and  and polydydroxy ketones.
                      Monosaccharides:  They  are  soluble  in  water.  These  include  non-hydrolysable
                        carbohydrates e.g. glucose, fructose.
                      Disaccharides: Which on hydrolysis give two molecules of monosaccharides e.g. cane
                        sugar, maltose, lactose.
                      Oligosaccharides:  The  carbohydrates  on  hydrolysis  give  2-10  monoaccharides  on
                        hydrolysis e.g. starch, amylase, amylopctin, glycogen, cellutos etc.
                      Sugars: include monosaccharides and oligosoaccharides.
                      Non sugar: starch, cellulose etc.
                      Reducing sugars: Those carbohydrates which contain free aldehydic or ketonic  group
                        and reduce fehling’s solution and Tollen’s reagent are known as reducing sugar e.g.
                        maltose.
                      Non-reducing  sugars:  Those  carbohydrates  which  do  not  have  free  aldehydic  or
                        ketonic group and do not reduce Fehling’s solution and Tollen’s reagent are know as
                        non-reducing sugar e.g. sucrose.
                      Cyclic structure of glucose:












                      Mutarotation:
                                                                                   o
                        When glucose is crystallized from a concentrated solution at  30 C , it gives   form of
                        glucose.     glucose is obtained on crystallization of glucose from a hot saturated aqueous
                                                        o
                        solution  at  a  temperature  above  98 C .  This  two  forms  are  called  anomers.  If  either  two
                        forms is dissolved in water  and  allow to stand, the specific rotation of  a solution changes
                                                              o
                                                         
                        slowly and reaches a constant value of  52.5 C , by process of mutarotation.
                      Proteins:  These  are  complex  polyamides  formed  from  amonoacids.  These  contain
                        both acid group as well as amino group.
                      Amino acids: These contain carboxylic group (-COOH) and amino group ( NH )
                                                                                          
                                                                                              2
                                                   
                         amino acids:if –COOH and  NH  groups are present in same carbon.
                                                      2
                      Acidic amino acids: which contains two carboxylic groups and one amino group e.g. aspartic
                        acid, glutamic acid.
                      Basic  amino  acids:  which  contains  two  amino  groups,  one  carboxylic  group  e.g.  argincine,
                        lysine, histidine.
                      Neutral  amino  acids;  Which  contains  one  acid  group  and  one  amino  group.  E.g.  clybine,
                        alanine, valine etc.
                      Essential amino acids: which are not synthesized by our body e.g. valine leucine, isoleucine,
                        phenyl alanine, methinine, tryptophan, threonine etc.
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