Immunity (chapters 10-11) Flashcards
infectious disease
A disease passed from one person to another by infection with microorganisms; also called an infectious or transmissible disease
contagious
A disease passed on by direct contact
pathogen
A disease-causing organism; also referred to as a pathogenic organism
vector
An agent such as an insect capable of transferring a disease-causing organism from one person to another
bacteria
Microscopic living organisms that cause disease; classified according to shape
cocci
Spherical cells that may occur singly, in pairs, in clusters or in chains
bacilli
Have flagella (for movement); are rod-shaped cells
spirilla
Have twisted cells
vibro
Are like curved rods (often shaped like a comma)
virus
An infectious agent, too small to be seen with a light microscope, consisting of a protein sheath surrounding a core of nucleic acid; viruses are totally dependent on living cells for reproduction
bacteriophages
A virus that infects bacteria
antibody
A substance produced in response to a specific antigen; combines with the antigen to neutralize or destroy it
antigen
Any substance capable of causing formation of antibodies when introduced into tissue
antigen-antibody complex
A compound formed when an antibody combines with an antigen
self-antigen
Any large molecule produced in a person’s own body; does not cause an immune response in that person
phagocytes
Cells that are able to engulf microorganisms and cell debris
macrophages
A phagocytic cell derived from a monocyte (a type of WBC)
leucocytes
A white blood cell
inflammation
The response to danger to a tissue; involves swelling, heat, pain and redness in the affected area
histamine
A substance released in response to injury to cells; it results in an increase in blood flow
herapin
A substance that helps to prevent blood clotting
lymphatic system
A system of vessels that drain excess fluid from the tissues
humoural/antibody-mediated immunity
A response triggered by foreign substances or microorganisms entering the body
cell-mediated immunity
The part of the immune response in which T-cells attach to antigens to destroy them; also called cellular immunity
B-cells
Produced in bone marrow, matures in bone marrow; a type of lymphocyte that develops into either a plasma cells that produces antibodies or into a memory cell
T-cells
Produced in bone marrow, matures in the thymus; a lymphocyte that can differentiate into a number of different kinds of cells, all of which are involved in cell-mediated immunity
killer T-cells
A type of T-lymphocyte able to kill cells that are damaged or infected with viruses or bacteria
Helper T-cells
Helper T-cells A type of T-cell that, among other things, enhances antibody production by B-cells
plasma cells
A cell that develops from a B-cell and produces antibodies
memory cells
A type of cell that recognizes an antigen to which the body has been previously exposed
primary response
The response of the immune system to the first expose to an antigen
secondary response
The response to a second or subsequent exposure to an antigen; does not cause an immune response in that person
agglutination
The clumping together of microorganisms or blood cells
natural immunity
Immunity that occurs without any human intervention
artificial immunity
Immunity produced by giving a person an antigen, which triggers the immune response, or by giving a person antibodies to an infecting agent
passive immunity
Immunity that is produced by the introduction of antibodies from another person
active immunity
Immunity produced by the body manufacturing antibodies against a foreign antigen
immunisation
Programming the immune system so that the body can respond rapidly to infecting microorganisms
narrow-spectrum antibiotics
An antibiotic that only affects a particular type of bacteria
broad-spectrum antibiotics
An antibiotic that affects many types of bacteria
bacteriostatic antibiotics
A drug used to treat bacterial infections; it does not kill the bacteria but stops them reproducing
bacteriacidal antibiotics
A drug used to treat bacterial infections by killing the bacteria
antiviral
A drug used for the treatment of viral infections
name the 8 non-specific external defences
skin, mucous membranes, hairs, cilia, acids, lysozyme, cerumen, flushing action
skin
covers outside of body and prevents microorganisms fro entering (openings protected by other defences), large amounts of bacteria live on the skin, which makes it difficult for pathogens to become established
mucous membranes
line body cavities that open to the exterior, inhibits the entry of microorgansism
hairs
nose and ear cavities
cilia
tiny hair-like projections from cells, capable of a beating motion to move mucous to the throat
acids
stomach juices are highly acidic to kill bacteria
lysozyme
enzyme that kills bacteria, found in the eyes, saliva, sweat, secretions of the nose, tissue fluid
cerumen
ear wax, protects outer ear from infection by some bacteria, slightly acidic + contains lysozyme
flushing action
keeps areas relatively free of pathogens, urine = cleansing action
what are the 4 non specific internal responses?
phagocytes, inflammation, fever, lymphatic system
phagocytes
phagocytes: cells that can engulf and digest microorgansims and cell debris
what are the three purposes of inflammation?
- reduce the spread of pathogens, destroy pathogens, prevent the entry of additional pathogens
- remove damaged tissue and cell debris
- being repair of damaged tissue
what are the four signs of inflammation? Account for them?
- redness –> increased flow of blood due to histamine
- swelling –> escape of fluid from blood
- heat –> increased blood flow due to histamine
- pain –> stimulation of pain receptors
what is the process of inflammation?
- when cells are stimulated by mechanical damage or local chemical changes, mast cells release histamine, herapin and other substances
- histamine increases blood flow and blood capillaries become more permeable so that fluid is filtered from the blood
- herapin prevents clotting
- chemicals released from mast cells attract phagocytes to actively consume microorganisms and debris
- pain receptors are stimulated
- phagocytes begin to die (pus)
- new cells are produced by mitosis and repair occurs
fever
high body temperatures are thought to help kill bacteria.
the person feels cold, so vasoconstriction and shivering occurs which increases body temperature
when is antibody-mediated (humoural) immunity activated?
when pathogens have not yet entered cells
when is cell-mediated immunity activated?
when pathogens (such as viruses) have entered the cell
describe the process of antibody-mediated immunity?
DO WITH CORRECTED NOTES
describe the process of cell-mediated immunity?
DO WITH CORRECTED NOTES
what are the four vaccine types?
- living attenuated microorganisms: viruses have a reduced ability to produce symptoms
- dead microorganisms: not prolonged immunity
- bacterial cultures containing toxins: bacteria produce their effect by liberating toxins, toxins are usually inactive
- sub-unit: fragment of an organism is used
