Phagocytosis is the method by which solid food is ingested in Amoeba.

Phagocytosis is a type of endocytosis, a process by which cells engulf and internalize solid particles or large molecules. It is a vital method of nutrient acquisition and is commonly observed in unicellular organisms like Amoeba.

Process of Phagocytosis in Amoeba:
1. Recognition: Amoeba extends its pseudopodia (temporary projections of the cell membrane) towards the solid food particle, such as a bacterium or an organic debris. The pseudopodia surround the particle and form a cup-shaped structure called a phagosome.

2. Engulfment: The pseudopodia continue to extend and fuse around the phagosome, enclosing it completely within a membrane-bound vesicle called a food vacuole. The food vacuole is separate from the cytoplasm and contains the ingested food particle.

3. Fusion with lysosomes: The food vacuole then fuses with lysosomes, which are membrane-bound organelles containing digestive enzymes. This fusion forms a phagolysosome, where the digestive enzymes are released.

4. Digestion: The digestive enzymes within the phagolysosome break down the ingested food particle into smaller molecules, such as amino acids, sugars, and lipids. These molecules are then absorbed by the amoeba for energy and other metabolic processes.

5. Excretion: After digestion, the undigested waste materials are expelled from the amoeba's body through a process called exocytosis. The residual waste is released from the food vacuole, and the vacuole is then reabsorbed into the cytoplasm.

Phagocytosis is a crucial process for the survival and nutrition of amoebae. It allows them to obtain nutrients from their environment and maintain their cellular functions. This method of feeding is highly efficient and enables amoebae to adapt to various environmental conditions.

In conclusion, phagocytosis is the primary method by which solid food is ingested in amoeba. It involves the recognition, engulfment, fusion with lysosomes, digestion, and excretion of the ingested food particles.