2.7 Innate (non-specific) Immune Response Flashcards
(18 cards)
What are the two main sections of the immune system?
Non-specific defence mechanisms and Specific defence mechanisms
Non-specific mechanisms attack any pathogen, while specific mechanisms target specific antigens.
What is the first line of defence in the immune system?
Physical and chemical barriers that are always ready to defend the body
This includes innate immunity.
Define innate immunity.
Inborn or natural immune response inherent to the host
Present in all animals and invertebrates.
What is the role of sensor systems in the immune response?
Detect when a pathogen breaches the first defence barriers and induces an innate immune response
This triggers the adaptive immune response subsequently.
Name the components of the second line of defence in the innate immune response.
- Phagocytes (WBC)
- Inflammation
- Fever
- Role of Histamine
- Role of Complement
- Natural Killer (NK) cells
What is phagocytosis?
The process by which phagocytes engulf bacteria, foreign particles, and dying cells
Phagocytes internalize pathogens in a phagosome.
What are the two main types of white blood cells?
- Phagocytes - Innate
- Lymphocytes - Acquired
What is the function of macrophages?
To free the airways, blood, and lymph of bacteria and other particles
Macrophages are larger and occur primarily in the lungs, liver, spleen, and lymph nodes.
What distinguishes neutrophils from macrophages?
Neutrophils are smaller, more abundant, and travel through circulating blood to reach infected areas
They can also engulf particles upon accidental collision.
What do natural killer (NK) cells recognize?
Protein markers as ‘non-self’ on cells that need to be destroyed
They attack abnormal cells, including virus-infected and cancer cells.
What is the complement system?
A set of proteins produced by liver cells that enhance the ability of antibodies and phagocytic cells to remove pathogens
Activated by a pathogen or an antibody bound to a pathogen.
What are interferons (IFNs)?
Proteins secreted by virus-infected cells that interfere with viral replication
They activate immune cells and increase the ability of uninfected host cells to resist new infections.
What characterizes the inflammatory response?
Redness, swelling, pain, and heat
Resulting from capillary dilation and increased blood flow to the area.
What is the purpose of a fever?
To raise body temperature above the normal growth temperature of pathogens and increase immune response
Fevers help slow down activities to allow the body to rest and fight infections.
Fill in the blank: The innate immune system is _____, rapid, not learned, and works in a similar way each time there is an infection.
non-specific
What is pus?
The accumulation of dead bacteria and phagocytes
Often found at the site of infection.
What is a boil?
An inflamed area that swells, builds pressure, and eventually bursts
Indicates a localized infection.
What role do platelets play in the inflammatory response?
Seal wounds and prevent further infection
They accumulate at the site of damage.
