Holozoic nutrition (Gr. holo, whole + zoikos, of animals) is a method of nutrition that involves the ingestion of liquid or solid organic material, digestion, absorption and assimilation of it to utilize it.It includes taking in the complex substances and converting them into simpler forms. Example, proteins can be broken into amino acids. This method suggests phagocytosis where the cell membrane completely surrounds a food particle.[1]
Most of the free living animals including humans exhibit this type of nutrition. In this mode of nutrition, the food may be a small bacterium, a plant or an animal. Here,the food is first taken into the body through an opening called a mouth (ingestion), then it is converted into a simple and soluble form by various enzymes (digestion); simplified products thus formed are then absorbed (absorption); the conversion of nutrient into the fluid or solid substance of the body (Assimilation); and finally the undigested part of food is removed from the body (egestion). This type of nutrition occurs mainly in single celled organisms such as Amoeba.