Final answer:
The two classes of vitamins are fat soluble vitamins, which include vitamins A, D, E, and K, and water soluble vitamins, which include the B-complex group and vitamin C. These vitamins are organic compounds necessary for maintaining various physiological functions such as vision and blood clotting.
Step-by-step explanation:
Vitamins are organic compounds that the body needs in small amounts for proper functioning. They are divided into two classes: (1) fat soluble vitamins and (2) water soluble vitamins.
The fat soluble vitamins include vitamins A, D, E, and K. They are stored in the body's fat tissues and liver and are released as needed. For instance, Vitamin A is essential for maintaining good vision, while Vitamin K is necessary for normal blood clotting.
The water soluble vitamins include the B-complex group of vitamins and vitamin C. These vitamins are not stored in the body and must be taken regularly in the diet. Vitamin B9 (folate) helps form red blood cells, and Vitamin C is important for the growth and repair of tissues in all parts of the body.