Disease And Pathogens Flashcards
Define phagocytosis:
Through the second line of defence when phagocytes destroy foreign matter.
Define phagocytes:
(White blood cells) that engulf and destroy any foreign matter (pathogens) that gets into the body.
Define antigen :
Specific chemicals on the pathogen.
Define pathogen:
A disease causing agent
Define histamine:
A chemical that causes inflammation, itchy throat and runny nose. The symptoms are designed to expel or limit pathogens.
Diseases can be spread by air:
Sneezing, coughing . Flu
Diseases can be spread by water:
Dirty water etc.
Diseases can be spread by contact:
Physical
Diseases can be spread by vectors:
Animals - Mosquitos (malaria) etc.
3rd line of defence
Specific memory cells eg. Chicken pox, antibodies and antigens…. Antihistamines
2nd line of defence
Phagocytes- inflammation (fever)
1st line of defence
Non specific- eg. Stomach acids, skin (intact), saliva
Why do we take antihistamine tablets?
To remove the symptoms caused by the body mistaking harmless substances for harmful pathogens (allergic reaction)
Interferon (2nd line of defence)
Attacked by the pathogen, signals neighbouring cells and they activate defence mechanisms (activate immune cells that come to affected area)
Mast cells
Release histamine (causes inflammation)
What is an antigen??
A chemical on the surface of a pathogen
What are antibodies ?
Specific proteins that destroy pathogens.
What is given to the body in a vaccination?
Dead or weakened pathogens or part of their antigens
How does vaccination work?
Memory cells are produced. They remain in the body to produce the necessary antibodies if there is a infection of a live pathogen.
When your immune system produces memory cells against a pathogen you get:
Acquired immunity.
There is no vaccine available for :
HIV/ AIDS
What type of microbe is the smallest?
Virus
How can infectious diseases spread?
The harmful microbe passes from person to person
Betadine is an
Antiseptic
