The Monroe County Women’s Disability Network (MCWDN) states that the paramecium takes in oxygen and gives off carbon dioxide through its cell membrane. A paramecium is a type of protozoa, which is a one-celled animal that is considered the tiniest of animals.
The MCWDN explains that the paramecium breathes, moves and reproduces like a multi-celled animal. It lives in water and damp places. Other animals in the protozoan group are the amoeba and euglena. Some protozoans are helpful as they feed on harmful bacteria and serve as food for fish and other animals. Others are harmful to humans as they transmit serious diseases.
The paramecium has no inner or outer skeleton, and it moves in various ways, the MCWDN elaborates. It eats bacteria and tiny algae in the water and stores food in sacs called vacuoles. It reproduces through fission, which is a process of splitting in half. It is typically asymmetrical and very microscopic in size. Water, which contains oxygen and food, flows in through the pores.
The Kidport Reference Library explains that aside from breathing in oxygen and breathing out carbon dioxide, the cell membrane is also used to absorb food in some protozoans. Others surround and consume their food or use their openings to gather food. Food is digested in their vacuoles.