Physiological function of vitamin C-

1) It is involved in oxidation-reduction of the cell. It is a donor of reducing equivalents in certain key reaction.
2) It is involved in the conversion of folic acid to the active form, tetrahydrofolic derivative.
3) It is involved in tyrosine metabolism i.e. oxidation of p-hydroxyphenyl pyruvate to homogentisate.
4) It is used in absorption of iron by converting the inorganic ferric iron to the ferrous form.
5) It is essential for the activity of fibroblasts, osteoblasts and odonoblasts. It causes hydroxylation of proline in collagen synthesis.

Biochemical role of vitamin ‘K’

Compound having vitamin k activity are naphthoquinone, chemically it is a phytomenadione. The two naturally occurring vitamin k are vitamin K1 and vitamin K2.
Biochemical function-
1) It reduces the prothrombin time.It is associated with the electron-transport chain and oxidation phosphorylation