Defensive Reading Flashcards
What are the 3 surface defenses of the innate defense system
Skin
Hair
Mucus
What are the 4 internal defenses of the innate defense system
- Mast Cells and Basophiles
- Natural Killer Cells
- Complement System
- Phagocytes ( Monocytes, Macrophages, Neutrophils)
What makes the skin protective
Covered with a layer of dead, keratinized epithelium that is too dry for bacteria in which to grow and is shed continuously
sweat and other skin secretions may lower pH, contain toxic lipids, and physically wash microbes away.
What makes saliva protective
rich in lysozyme—an enzyme that destroys bacteria by digesting their cell walls.
What makes the stomach a protective barrier
The acidic environment of the stomach, which is fatal to many pathogens,
What makes the upper respiratory tract a protective barrier
Ciliated epithelial cells move potentially contaminated mucus upwards to the mouth, where it is then swallowed into the digestive tract, ending up in the harsh acidic environment of the stomach.
What is a phagocyte
A phagocyte is a cell that is able to surround and engulf a particle or cell,a process known as phagocytosis
What is body’s fast acting, first line of immunological defense against organisms that have breached barrier defenses and have entered the vulnerable tissues of the body.
Phagocytes
What are the major phagocytes of the immune system
Macrophages, neutrophils, and dendritic cells
What is a macrophage
an irregularly shaped phagocyte that is amoeboid in nature and is the most versatile of the phagocytes in the body.
move through tissues and squeeze through capillary walls using pseudopodia
agranulocyte
What type of phagocyte is the first line of defense when pathogens breach the body’s barriers
macrophages
What are the different names for macrophages and their locations
Kupffer cells in the liver
Histiocytes in connective tissue
Alveolar macrophages in the lungs.
What is a neutrophil
a phagocytic cell that is attracted via chemotaxis from the bloodstream to infected tissues
spherical in shaper
granulocytes
thought of as military reinforcements that are called into a battle to hasten the destruction of the enemy
primary pathogen-killing cell of the inflammatory process of the innate immune response,
What is a granulocyte and what is an agranulocyte
A granulocyte contains cytoplasmic granules, which in turn contain a variety of vasoactive mediators such as histamine
Neutrophils
An agranulocyte has few or no cytoplasmic granules
Macrophages & Monocytes
What is the primary location of Macrophages, Neutrophils, and Monocytes
Macrophages - body cavaties and organs
Neutrophils - blood
Monocytes - blood
What is the main function in the innate immune system of the Macrophages, Neutrophils and Monocytes
Macrophages- phagocytocis
Neutrophils- Phagocytosis
Monocytes - Precursor of macrophage/dendritic cell
What is a monocyte
circulating precursor cell that differentiates into either a macrophage or dendritic cell, which can be rapidly attracted to areas of infection by signal molecules of inflammation.
What are Natural Killer Cells
a type of lymphocyte that have the ability to induce apoptosis, that is, programmed cell death, in cells infected with intracellular pathogens such as obligate intracellular bacteria and viruses.
What is apoptosis
programmed cell death… a cascade of events inside the cell causes its own death by either of two mechanisms
What are the two ways Natural Killer cells cause apoptosis
NK cells are able to respond to chemical signals and express the fas ligand
The granules of the NK cells release perforins and granzymes
What is a fas ligand
a surface molecule that binds to the fas molecule on the surface of the infected cell, sending it apoptotic signals, thus killing the cell and the pathogen within it;
What is a perforin and what is a granzyme
a protein that forms pores in the membranes of infected cells. A granzyme is a protein-digesting enzyme that enters the cell via the perforin pores and triggers apoptosis intracellularly
What is a pattern recognition receptor (PRR)
a membrane-bound receptor that recognizes characteristic features of a pathogen and molecules released by stressed or damaged cells.
how phagocytic cells, and the cytotoxic NK cells recognize patterns of pathogen-specific molecules, such as bacterial cell wall components or bacterial flagellar proteins
What is a cytokine
Signaling molecule that allows cells to communicate with each other over short distances.
Cytokines are secreted into the intercellular space, and the action of the cytokine induces the receiving cell to change its physiology.
