2.2 - Living Processes in Unicellular Organisms

Unicellular organisms are single-celled organisms. They only consist of one cell. Despite so, they are capable of performing all living processes such as respiration, growth, movement, reproduction, feeding and excretion. The two most common examples of unicellular organisms are Amoeba sp. and Paramecium sp.

Figure 3 - Amoeba sp. can normally be found in freshwaters.

Figure 4 - Paramecium sp. is commonly known for its characteristics shoe-shaped appearance. It is also mostly found in freshwaters.

Figure 5 - The process of binary fission of Amoeba sp. 1. Parent cell of Amoeba sp. 2. Nucleus division starts first. 3. Then, cytoplasm begins to split. 4. Two new daughter cells are formed.

Figure 6 - The process of feeding in Amoeba sp. 1. Amoeba sp. extends its pseudopodia (false feet) and engulf the food particle. 2. The ingested food is then packed into a vacuole. 3. Lysosome in the cell combine with the food vacuole and releases enzymes to digest the food. 4. Digested food particles are absorbed into the cytoplasm. 5. Undigested materials are excreted as waste products.