Immune System Chapter 31

Germ theory – diseases are caused by specific microorganisms Germ theory – diseases are caused by specific microorganisms. Pathogen - agents that cause infectious diseases. Examples are viruses, some bacteria, and parasites.

Vector – anything that transmits pathogens into healthy cells Vector – anything that transmits pathogens into healthy cells. Common examples include MOSQUITOES, snails, ticks, beetles, and flies.

Immune System – fights off pathogens in the body Immune System – fights off pathogens in the body. Phagocyte – the cell that destroys pathogens.

B Lymphocytes (B cells) – inactivate pathogens by making antibodies. T Lymphocytes (T cells) – destroy infected body cells. B Lymphocytes (B cells) – inactivate pathogens by making antibodies.

Antibodies make pathogens ineffective by sticking to them Antibodies make pathogens ineffective by sticking to them. Interferons are proteins released by infected cells that prepare uninfected cells for defense.

Inflammation - response to infection or tissue damage involving redness, swelling, and itching. Memory cells – T and B cells that quickly destroy pathogens that made you sick in the past.

Antigen – viral and bacterial proteins that help your body identify foreign invaders.

Vaccine – substance that makes you produce memory cells without you getting very sick. If a pathogen invades your body after being vaccinated, your B-cells make VERY specific antibodies to fight THAT particular pathogen.

Antibiotics DO NOT work on viruses such as the flu or cold viruses Antibiotics DO NOT work on viruses such as the flu or cold viruses. Antibiotics kill bacteria. Some bacteria can become resistant to antibiotics if you do not take all of it as directed by doctors.