Some types of white blood cells, called phagocytes (FAH-guh-sytes), chew up invading organisms. Others, called lymphocytes (LIM-fuh-sytes), help the body remember the invaders and destroy them. One type of phagocyte is the neutrophil (NOO-truh-fil), which fights bacteria.

The antibodies destroy the antigen (pathogen) which is then engulfed and digested by macrophages. White blood cells can also produce chemicals called antitoxins which destroy the toxins (poisons) some bacteria produce when they have invaded the body.

Via phagocytosis Opsonised bacteria are, therefore, coated with molecules that phagocytic cells recognise and respond to. Activated phagocytes engulf and destroy opsonised bacteria by a process called phagocytosis.

Neutrophils are the most common type of white blood cell. These cells travel to the site of an infection and release substances called enzymes to fight off invading viruses or bacteria. Lymphocytes. There are two main types of lymphocytes: B cells and T cells.

Antibodies bind to viruses, marking them as invaders so that white blood cells can engulf and destroy them.

Researchers at Oregon Health and Science University have demonstrated how certain white blood cells literally eat virus-infected cells while fighting disease at the microscopic level.

Viruses make us sick by killing cells or disrupting cell function. Our bodies often respond with fever (heat inactivates many viruses), the secretion of a chemical called interferon (which blocks viruses from reproducing), or by marshaling the immune system’s antibodies and other cells to target the invader.

A most common type of viral disease is the common cold which is caused by the infection in the upper respiratory tract. 1)Virus in some cases can cause serious life-threatening conditions such as dehydration or pneumonia. 2) Viruses are also called diseases by disturbing and organisms’ homeostasis.

Many viral diseases are controlled by reducing exposure to the virus by (1) eliminating nonhuman reservoirs, (2) eliminating the vector, and (3) improving sanitation.

Discovery of the Giant Mimivirus. Mimivirus is the largest and most complex virus known.

On a biological level, the main difference is that bacteria are free-living cells that can live inside or outside a body, while viruses are a non-living collection of molecules that need a host to survive.

How do viruses spread? Once a person is infected with a virus, their body becomes a reservoir of virus particles which can be released in bodily fluids – such as by coughing and sneezing – or by shedding skin or in some cases even touching surfaces.

There are two processes used by viruses to replicate: the lytic cycle and lysogenic cycle. Some viruses reproduce using both methods, while others only use the lytic cycle. In the lytic cycle, the virus attaches to the host cell and injects its DNA.