mRNA, tRNA, rRNA

The main structural feature of reducing sugars is the presence of an aldehyde group (-CHO) such as in glucose , mannose, gatactose, etc or the \(\alpha\) - ketol grouping (-CO-CH₂OH) as present in fructose.

(i) Peptide linkage: The amide  linkage between two a-amino acids formed with the loss of a water molecule is called a peptide linkage.
(ii) The six membered cyclic structure of glucose is called pyranose structure (α - or β -), in analogy with heterocylic compound pyran glucose

Those sugars which have free aldehyde group and give brick red precipitate with Fehling's solution are called reducing sugars.

(a)The process of disruption of higher structure without changing its primary structure is called denaturation. If the disruptive agent is removed and protein recovers its original structure, it is called renaturation.
(b)In stomach pH is acidic, therefore, amylase becomes inactive, that is why digestion of carbohydrates does not take place in stomach.

(a) Isoelectric point: It is the pH at which +ve and -ve charges on zwitter ion are equal, e.g., amino acid exists as zwitter ion at pH =5.5 to 6.3.
(b) Mutarotation : It is a spontaneous change in optical rotaion when an optically active substance is dissolved in water, e.g., \(\alpha\)-glucose, when dissolved  in water, its optical rotaion changes from 111^o to 52.5^o.
(c)Enzymes : They are biological catalysts which catalyse specific biochemical reactions, e.g., 
\(\underset { sucrose }{ C_{ 12 }H_{ 22 }O_{ 11 } } +H_{ 2 }O\quad \overset { invertase }{ \longrightarrow } \underset { Glucose }{ C_{ 6 }H_{ { 12 } }O_{ 6 } } +\underset { Fructose }{ C_{ 6 }H_{ 12 }O_{ 6 } } \)
Most of enzymes are globular proteins.

(i) Co-enzymes : Those prosthetic groups which get attached to enzymes at the time of reaction are called co-enzymes. These increase the activity of enzymes.
(ii) Mutation in Biomolecules : A difference of a single base in DNA molecule can cause change in amino acid sequence which leads to mutation.
(iii) Nucleotides : They are monomers of nucleic acids. They consist of heterocyclic base, pentose sugar and phosphoric acis residue.

(i) Concern for health of other person, kind, intelligent.
(ii) Vitamin B₁₂
(iii) Vitamin B / Vitamin C

During osazone formation, the reaction occurs only at CI and C2 while rest of the molecule remains intact. Since glucose and fructose differ from each other only in the arrangement of atoms at CI and C2, therefore, they. give the same osazone.