Cell Recognition And The Immune System Flashcards
Proteins on molecules enable the immune system to identify …x4
Pathogens
Cells from other organisms of the same species
Abnormal body cells
Toxins
What is an antigen
Foreign protein generate an immune response when detected by lymphocytes in the body
Define a pathogen
A microorganism that can cause diseases
Name x4 types of pathogen
Bacteria
Virus
Fungi
Protists
What are abnormal body cells
Cancerous or pathogen infected cells that have abnormal antigens on their surface that trigger an immune response
Are toxins molecules or cells
Molecules
Why can antigen variability be a problem
Antigens change frequently due to mutations
This is a problem because lymphocytes and memory cells produce a specific immune response
Bind to one antigen once changed it can no longer bind
What is the bodies first line of defence
Skin
Which white blood cells which are specific and which are non-specific
Phagocytes - non-specific
Lymphocytes- specific
What type of white blood cell is a macrophage
Phagocytes
Is phagocytosis specific or non-specific
Non-specific
Where are phagocytes found
Tissue
Blood
Stage 1 of phagocytosis
Pathogens release chemicals
Phagocytes follow the trail and moves towards these cells
The phagocytes have many receptors that will attach to the chemicals or antigens on the pathogen
The phagocyte changes shape to move around and engulf the pathogen
Once engulfed the pathogen forms a phagosome and fuses with a lysosomes
The lysozymes digests the pathogen
The phagocyte then presents the pathogens antigens on it surface to activate other immune system cells.
The phagocyte is an anti-gen presenting phagocyte
What is the purpose of disulphide bridges in a antibody
Joins two polypeptide chains
What type of cell are T-lymphocytes
White blood cell
Are T-cells specific or non-specific
Specific
Where are lymphocytes made
In bone marrow
What is cell-mediated response
The response involves T-cells and body cells
No antibodies
What is an antigen presenting cell
Any cells that presents a non-self antigen on the cell MEMBRANE
Name x2 antigen presenting cells
Macrophages
Cancer cells
How do T-cells work
They have receptors which attach onto the antigens on an antigen-presenting cell
One attached they are activated and divide by mitosis to produce large number of clones
The cloned helper T-cells differentiate into different cells
What can T-cells do x3
Helper T-Cells stimulate phagocytes
Activate B-cells to secrete anti toxins
Cytotoxic T-Cells kill foreign cells
How do cytotoxic T-Cells work
Release perforin which embeds into cell surface membrane and make a pore
Because any substance can leave or enter the cell dies
Are B-lymphocytes specific or non-specific
Specific
What does humoral response involve
B cells
Antibodies