GK From Digestion and Absorption: Fatty acids which possess one or more double bonds in their hydrocarbon chain are called- Unsaturated fatty acids. Fats stored in special cells called- Adipocytes. Deficiency of Vitamin D, Calcium, and Phosphorous causes- Osteomalacia. Deficiency of which vitamin results in a decreased life span of erythrocytes- Vitamin E. Enlargement of