Folic acid (folacin) and pantothenic acid (vitaminB3 ) belong to vitamin-B complex along with thiamine, riboflavin, pyridoxine, niacin, biotin and cyanocobalamin.
Deficiency of vitamin-C (ascorbic acid) leads to disease scurvy.
Deficiency of vitamin-K (phylloquinone) causes haemorrhage.
Deficiency of vitamin-A (retinol) cause xerophthalmia, night blindness, keratomalacia, retarded growth, etc.