Immune System Flashcards
Explain how diseases may be contracted directly or indirectly.
They can be contracted by touching someone who is infected (direct) or coming in contact with air where someone has coughed or sneezed (indirect).
What is a vector?
An animal that carries pathogens from person to person.
How does one get food poisoning?
How does one avoid it?
By eating food contaminated with pathogens.
Thoroughly cooking foods like meats.
What are antibiotics?
Compounds that kill bacteria without harming the cells of human or animal hosts.
What is the function of the immune system?
Definition of immunity
To fight and destroy infections by producing cells that inactivate foreign cells or substances.
What are nonspecific defenses?
Defenses in the immune system that do not discriminate between one threat and another.
What are specific defenses?
Also known as immune response, they are defenses in the immune system that target specific disease-causing agents.
What is the first line of defense? (Give function, examples)
The function of the first line of defense is to keep pathogens out of the body. These defenses include skin, mucus, sweat, tears and saliva.
Secretions of body contain an enzyme, lysozyme, that breaks down cell walls of bacteria.
Oil and sweat glands produce acidic environment that kills many bacteria.
Cilia that line nose and throat push pathogens away from lungs.
Stomach acid breaks down pathogens that get to stomach.
What is the second line of defense? (Give function, examples)
The function is to get rid of any pathogens that manage to enter the body. Inflammation (inflammatory response) is a nonspecific defense that happens when tissue damage is caused by injury/infection. {white blood cells (phagocytes) cause swelling when engulfing pathogens.}
Fever is a nonspecific defense that heats the body to kill pathogens and increase rate at which white blood cells are produced.
Interferons are proteins released by infected cells to prevent other cells from becoming infected.
What is an antigen?
Any substance that triggers an immune response.
Describe humoral immunity.
Immunity against antigens and pathogens in bodily fluids through B Cells.
Describe cell-mediated immunity.
Immunity against abnormal cells and pathogens inside living cells through T Cells.
Define antibodies.
Proteins that recognize and bind to antigens. Reduce chance of re-contracting a disease.
How do T cells work?
T cell divides into killer T cell, suppressor T cell, helper T cell and memory T cell. Killer T cell tracks down and destroys the pathogen, helper T cells produce memory T cells, memory T cells recognize antigens if they attack again and suppressor T cells release a substance that shuts down killer T cells when they are done.
What is a passive immunity?
Short term immunity when antibodies produced in another animal are injected into the body to fight a pathogen.
