The essential chemical components of many coenzymes are:
1. Nucleic acid
2. Carbohydrates
3. Vitamins
4. Proteins

For its activity, carboxypeptidase requires:
1. Iron
2. Niacin
3. Copper
4. Zinc

Which one of the following is a fat-soluble vitamin and its related deficiency disease?

1. Ascorbic acid - Scurvy

2. Retinol - Xerophthalmia

3. Cobalamine - Beri-Beri

4. Calciferol - Pellagra

An organic substance bound to an enzyme and essential for its activity is called:

1. coenzyme

2. holoenzyme

3. apoenzyme

4. isoemzyme