The cells in the body that engulf foreign particles like bacteria are called phagocytes. Phagocytes are a type of white blood cell that plays a crucial role in the immune system. They are responsible for identifying, attacking, and eliminating foreign invaders, such as bacteria and viruses, from the body. There are several different types of phagocytes, including neutrophils, monocytes, and macrophages, which are all part of the body's first line of defense against infection.

Method of killing

Phagocytes kill bacteria and other foreign invaders in a process called phagocytosis. When a phagocyte encounters a foreign particle, it extends pseudopodia (false feet) around the particle and engulfs it. The phagocyte then encloses the particle in a membrane-bound vesicle called a phagosome. The phagosome then moves to the center of the cell and fuses with a lysosome, which is a vesicle that contains enzymes that can break down the engulfed particle. The enzymes in the lysosome digest the particle and kill it, and the waste products are then expelled from the cell. This process is an essential part of the body's immune response and helps to keep us healthy by eliminating harmful foreign invaders.

Here are some additional points about the process of phagocytosis:

• Phagocytosis is a key process in the immune system that helps to protect the body from infection and disease.
• Phagocytes are able to recognize and target foreign particles through a variety of mechanisms, including the use of receptors on their surface that bind to specific molecules found on the surface of bacteria and other pathogens.
• Once a phagocyte has engulfed a particle, it can kill the particle in a number of ways. For example, the lysosome may release enzymes that break down the particle's cell wall or other structural components, or the phagocyte may produce reactive oxygen species (ROS) or other toxic substances that kill the particle.
• The phagocyte also releases chemical signals called cytokines, which help to attract other immune cells to the site of infection and coordinate the immune response.
• In addition to eliminating foreign particles, phagocytes also play a role in removing damaged or dead cells from the body. This helps to prevent the accumulation of debris and maintains tissue homeostasis.
• Phagocytosis is an energy-intensive process that requires the phagocyte to consume oxygen and glucose. As a result, phagocytes are highly metabolically active cells that are capable of producing large amounts of ATP (the energy currency of cells) through the process of cellular respiration.