3.5 Non-Specific Body Defences Flashcards
What are pathogens?
Organisms such as bacteria, fungi and viruses which can cause diseases
What is the function of the immune system?
To defend the body against pathogens and diseases
What is the immune system divided into?
- Non-specific defences
- Specific defences
What are epithelial cells?
A non-specific defence
Where are epithelial cells found?
In the skin and inner linings of the breathing and digestive systems
What do epithelial cells form a physical barrier against?
Pathogens
What do epithelial cells produce?
Secretions such as enzymes, hormones and lubirating fluids that can defend against infection
What is the inflammatory response?
A non-specific defence which is triggered when an injury or infection occurs
What do mast cells release?
Histamine
What starts the inflammatory response?
Mast cells releasing histamine
What do histamines cause?
Vasodilation and increased capillary permeability
What does an increased blood flow in the inflammatory response lead to?
Accummulation of phagocytes and clotting elements at the site of infection
What are phagocytes?
A non-specific type of white blood cell
What do phagocytes do?
Recognise foregin antigen molecules on the surface of pathogens and destroy them by phagocytosis
What is phagocytosis?
When the phagocyte engulfs the pathogen and destroys it by using digestive enzymes containe within lyosomes inside the phagocyte
