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SUBJECT-CHEMISTRY


                                               CHAPTER-BIOMOLECULES.


                 Carbohydrates: they are a class of compounds which include polyhydroxy aldehydes and
                    andpolydydroxy 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  slowly  and
                    reaches a constant value of  52.5 C  o  , 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  2   groups are present in same carbon.
                 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.
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