Phagocytosis Flashcards
What are white blood cells known as
Leukocytes
What do leukocytes recognise/do
Recognise self and non self chemicals and respond as part of the immune response
What are the 2 types of white blood cells
Lymphocytes and phagocytes
What are the 2 types of phagocytes
Neutrophils and macrophages
What is the similarity between neutrophils and macrophages
They both engulf pathogens
What are the differences between neutrophils and macrophages
Neutrophils have a multi lobed nucleus, macrophages have a single round nucleus
Neutrophils get to the infection site earlier, macrophages get there later
Neutrophils completely digest pathogens and kill them, macrophages transfer some of the pathogens on to their own surface membrane, making an antigen presenting cell
What is the first step of phagocytosis of pathogens?
Chemicals called mediators (eg cytokines) are released when cells are under attack/when the antigens on the pathogen is recognised
What is the 2nd step of phagocytosis of pathogens?
A phagocytes is attracted to the site of infection by the cytokines through the process of chemotaxis
The phagocyte will start to change shape around the pathogen
What is the 3rd step of phagocytosis of pathogens?
Recognition and attachment occurs
What is the 4th step of phagocytosis of pathogens?
The pathogen is engulfed by the phagocyte and forms a phagosome
What is the 5th step of phagocytosis of pathogens?
The fusion of lysosomes and phagosomes forms a phagolysosome
When the phagolysosome is formed, lysosomes release hydrolytic enzymes to break down and digest pathogens
What is the last step of phagocytosis of pathogens in a neutrophil?
The pathogen is digested and waste products leave the cell by exocytosis
What is the last step of phagocytosis of pathogens in a macrophage?
An antigen presenting cell is produced (APC)
