26. The vitamin riboflavin is part of the __________ molecule.

A. ferredoxin
B. FAD
C. pyridoxal phosphat
D. pyrophosphate

27. The most prominent role that tocopherol has in in-vitro systems is as a strong

A. antioxidants
B. reducing agent
C. oxidizing agent
D. all of these

28. Biotin occurs mainly in combined forms bound to protein through

A. ε-N-lysine moiety
B. ε-S-lysine moiety
C. ε-N-biotinyl-L-lysine
D. ε-N-lipoyl – L-lysine

29. Lipoic acid is a co-factor of the

A. pyruvic dehydrogenase
B. α-ketoglutaric dehydrogenase
C. both (a) and (b)
D. di-hydroorotate dehydrogenase

30. β-carotene together with α-carotene, γ-carotene and cryptoxanthine are synthesized by

A. plants
B. animal
C. plants and animals both
D. none of these