Sec 31.2: Immune System Flashcards
What is the immune system?
It is the body system that fights off infection and pathogens
what are your first line of protection?
The skin, Mucous, Cilia
What does the skin do?
It surrounds and protects your insides, physically blocking invading pathogens and secreting sweat and oils that make the skin hypertonic and acidic, an environment in which pathogens cannot survive
What does mucous do?
Mucous membranes in eyes, nose, ears, mouth, and excretory organs use hairlike cilia covered with a sticky liquid to trap pathogens
What are the six white blood cells that attack infections inside your body?
Basophils, Mast cells, Esinophils, Neutrophils, Macrophages, and Lymphocytes
What do basophils and mast cells have in common? Where do they differ?
Both send chemical signals that attract other white blood cells to the site of infection (causing inflammation). Basophils causes chemical signals in the bloodstream, while mast cells cause chemical signals in other body tissues
What do esinophils do?
If the pathogen is a parasite, it injects it with poisonous packets
What are phagocytes?
They are cells that destroy pathogens by surrounding and engulfing them
What do neutrophils and macrophages have in common? Where do they differ?
Both are phagocytes that attack if the pathogen is a bacteria, fungi, or virus. Neutrophils engulf pathogens and foreign invaders, while macrophages engulf dead or damaged body cells and bacteria
What do lymphocytes do?
They destroy infected body cells or produce proteins that inactivate pathogens
What do T lymphocytes do?
T cells destroy body cells infected with pathogens
What do B lymphocytes do?
B cells produce proteins (antibodies) that inactivate pathogens that have not infected a body cell
What are the 3 proteins that defend against infection?
Complement proteins, antibodies, and interferons
What are complement proteins?
They are proteins made by white blood cells and by certain organs
What do complement proteins do?
They weaken a pathogen’s cell membrane to allow water to enter and burst cell, or attract phagocytes to infected area, or cause microbes to stick to blood vessel walls to be found easily and destroyed by phagocytes
