Phagocytosis Flashcards
What does the immune system do?
Allows cells to develop resistance to infection.
What are the two defences against pathogens?
Non-specific & Specific
What’s a non-specific response?
This response happens instantly as it does not distinguish between pathogens.
What’s a specific response?
A response that targets a specific pathogen that’s recognised as non-self.
What are the non-specific responses in the body?
Barriers & Phagocytosis
What are the specific responses?
Cell-mediated & Humoral.
What cells does a cell-mediated response use?
T
What cells does a humoral response use?
B
How can pathogens enter the body?
Through interfaces.
What is an interface?
Allows pathogens to enter the body through an exchange with the environment.
What is an example of an interface?
Cuts, organ systems, tear ducts etc.
How does skin provide a physical barrier against pathogens?
It’s thick, the top layer is dead (pathogens can shed off with it) and there is already bacteria collonated making it difficult for pathogens to do so.
What are 2 examples of chemical defences?
Hydrochloric acid & tears (lysozyme)
How can mucus act as a barrier? (2 reasons)
- Pathogens get trapped and carried away by cillia.
- Mucus is thick & difficult to get through.
What type of cell are phagocytes?
White blood
How do lysosomes assist the digestion of the pathogen?
They contain hydrochloric enzymes that break down pathogens as they digest the proteins that the pathogen needed to survive.
What does lysozyme do?
Hydrolises the proteins in bacteria before they can enter the body.
What is histamine?
A chemical that causes blood vessels to dilate.
What is the benefit of histamine?
If the blood vessels expand, more white blood cells can reach the infected area and therefore more pathogens then have to go through the process of phagocytosis.
How many types of pathogens are there?
4
What are the types of pathogens?
Viruses, fungi, bacteria, protoctista.
