5.2: Phagocytosis Flashcards
Phagocytosis
Phagocytosis is the process in which invading microorganisms are:
1. Engulfed
2. Destroyed
by specific white blood cells known as phagocytes
If a pathogen is to infect the body, it must first do what?
If a pathogen is to infect the body, it must first gain entry
If a pathogen is to infect the body, it must first gain entry.
The body’s first line of defence is to form a physical or chemical barrier to entry.
Should this fail, the next line of defence is the white blood cells.
How many types of white blood cells are there?
There are 2 types of white blood cells:
- Phagocytes
- Lymphocytes
If a pathogen is to infect the body, it must first gain entry.
The body’s first line of defence is to form a physical or chemical barrier to entry.
Should this fail, the next line of defence is the white blood cells.
There are 2 types of white blood cells phagocytes and lymphocytes
Phagocytes ingest and destroy the pathogen by a process called phagocytosis before it can cause harm.
What are lymphocytes involved in?
Lymphocytes are involved in immune responses
Despite various barriers, pathogens still frequently gain entry and the next line of defence is then what?
Despite various barriers, pathogens still frequently gain entry and the next line of defence is then phagocytosis
In the blood, the types of white blood cells that carry out phagocytosis are known as phagocytes.
They provide an important defence against the pathogens that manage to enter the body.
Some phagocytes travel in the blood, but can do what?
Some phagocytes travel in the blood, but can move out of blood vessels into other tissues
The process of phagocytosis:
The phagocyte is attracted to the pathogen by what?
The phagocyte is attracted to the pathogen by chemical products of the pathogen
The process of phagocytosis:
The phagocyte is attracted to the pathogen by chemical products of the pathogen, causing the phagocyte to do what?
The phagocyte is attracted to the pathogen by chemical products of the pathogen, causing the phagocyte to move towards the pathogen along a concentration gradient
The process of phagocytosis:
The phagocyte is attracted to the pathogen by chemical products of the pathogen, causing the phagocyte to move towards the pathogen along what?
The phagocyte is attracted to the pathogen by chemical products of the pathogen, causing the phagocyte to move towards the pathogen along a concentration gradient
The process of phagocytosis:
The phagocyte is attracted to the pathogen by chemical products of the pathogen, causing the phagocyte to move towards the pathogen along a concentration gradient.
What does the phagocyte have on its cell-surface membrane?
The phagocyte has several receptors on its cell-surface membrane
The process of phagocytosis:
The phagocyte is attracted to the pathogen by chemical products of the pathogen, causing the phagocyte to move towards the pathogen along a concentration gradient.
The phagocyte has several receptors on its cell-surface membrane that do what?
The phagocyte has several receptors on its cell-surface membrane that:
1. Recognise
2. Attach to
chemicals on the surface of the pathogen
The process of phagocytosis:
The phagocyte is attracted to the pathogen by chemical products of the pathogen, causing the phagocyte to move towards the pathogen along a concentration gradient.
The phagocyte has several receptors on its cell-surface membrane that recognise and attach to chemicals on the surface of the pathogen.
What does the phagocyte do?
The phagocyte engulfs the pathogen to form a vesicle from the cell-surface membrane
The process of phagocytosis:
The phagocyte is attracted to the pathogen by chemical products of the pathogen, causing the phagocyte to move towards the pathogen along a concentration gradient.
The phagocyte has several receptors on its cell-surface membrane that recognise and attach to chemicals on the surface of the pathogen.
The phagocyte engulfs the pathogen to form a vesicle from the cell-surface membrane, known as a what?
The phagocyte engulfs the pathogen to form a vesicle from the cell-surface membrane, known as a phagosome
The process of phagocytosis:
The phagocyte is attracted to the pathogen by chemical products of the pathogen, causing the phagocyte to move towards the pathogen along a concentration gradient.
The phagocyte has several receptors on its cell-surface membrane that recognise and attach to chemicals on the surface of the pathogen.
The phagocyte engulfs the pathogen to form a vesicle from the cell-surface membrane, known as a phagosome.
What do lysosomes within the phagocyte do?
Lysosomes within the phagocyte:
- Move towards the vesicle
- Fuse with it
The process of phagocytosis:
The phagocyte is attracted to the pathogen by chemical products of the pathogen, causing the phagocyte to move towards the pathogen along a concentration gradient.
The phagocyte has several receptors on its cell-surface membrane that recognise and attach to chemicals on the surface of the pathogen.
The phagocyte engulfs the pathogen to form a vesicle from the cell-surface membrane, known as a phagosome.
Lysosomes within the phagocyte move towards the vesicle and fuse with it.
What do the lysosomes do?
The lysosomes release their lysozymes into the phagosome