Phagocytosis Flashcards
What is a phagocyte?
-they ingest and destroy the pathogen by a process called phagocytosis before it can cause harm
what is phagocytosis?
- large particles like some types of bacteria can be engulfed by cells in vesicles formed on the cell surge a membrane
- the types of white blood cells involved in phagocytosis are known as phagocytes which defend against pathogens that manage to enter the body’s blood stream most move out of the blood vessels into surrounding tissues
what does a phagosome do?
-phagosomes engulf pathogens to form a vesicle on the cell surface membrane
What is the body’s first line of defence to pathogens?
-physical or chemical barriers
What is the body’s second line of defence to pathogens?
White blood cells
What are lymphocytes?
- White blood cells that are involved in immune responses
- they are present within the lysosome
- these lysosomes destroy ingested bacteria by hydrolysis of their cell walls
What is a phagosome?
-a vacuole in the cytoplasm of a cell, containing a phagocytosed particle enclosed within a part of the cell membrane.
What are the types of white blood cell?
- phagocytes
- lymphocytes
What is the second stage of phagocytosis?
-the phagocyte has several receptors on its cell surface membrane that attach to chemicals on the surface of the pathogen
What is the third stage of phagocytosis?
-lysosomes within the phagocyte migrate towards the phagosomes formed by engulfing the bacterium
What is the fourth stage of phagocytosis?
-the lysosome release their lysozymes into the phagosomes where they hydrolyse the bacterium
What is the fifth stage of phagocytosis?
-the hydrolysis products of the bacterium ate absorbed by the phagocyte
What is the first stage of phagocytosis?
-the phagocyte is attached to the pathogen by chemical products of the pathogen so it moves towards the pathogen along a concentration gradient
