Immunity Flashcards
Immune system types
Adaptive immunity
Innate immunity
4 Source of specific immunity
Natural you get the illness and respond to it. By actively killing it. Then become immune
Induced, you get a illness immunisation and actively respond by killing it. Then become immune.
Given it from mother. Natural. Anything the mother is immune to the baby is also immune to. Run out over time. 6 weeks
Given it through injections of the proteins. After they have got the illness
Primary response
You have the bug
The IgG only starts working after the bug is gone
Secondary response
The IgG starts working right away
You don’t get the bug
It recognises it from last time
And remembers who to kill it
Antigens
Molecules on the outside of plasma membrane
Enables cells to be recognised
Each person has unique pattern graft versus host disease.
T and B Lymphocytes
Second most abundant white blood cell
Are very variable in size
Have receptor complex that will only bind to one highly specific antigen
Can be further classified as T or B lymphocytes, and these can be further classified eg T helper lymphocytes and cytotoxic T lymphocytes.
The difference between T and B lymphocytes
B lymphocytes make direct contact with the antigen
Matured in the lymph node, spleen or tonsils
They make antibodies uses chemicals
T lymphocytes need the antigen to be presented with a coreceptor.
Matured in the thymus gland
The cell it’s self kills the treat
Antigen presentation
The antigen is displayed on the surface of another cells plasma membrane
Lots of cells have this ability And called antigen presenting cell
How do T and B lymphocytes mature
this is where they learnt to distinguish them self and not the self.
They get ready to attack non self and keep self
If they do this they mature, if not they get destroyed
Only fully mature once met threat
Once met that threat, they can only kill that treat. become memory cell.
They will often replicate.
If a new treat appears it repeats with new lymphocytes
Innate immunity
The first line of defence.
Born with it for exam skin, mucous membranes, phagocytes
Uses surface membrane barriers, chemical and immune cells
Takes days and uses immune cells call lymphocytes
Surface membrane barriers
The skin provides a barrier to entry by pathogens - The acidic pH of skin inhibits bacterial growth
Mucous membrane forms a barrier to micro-organisms. Traps the micro-organisms.
Nasal hairs filter and trap micro-organisms
Gastric juice in the stomach contains hydrochloride acid and protein digesting enzymes
Acidity in vagina inhibits growth of micro-organism
Tears clean eyes
Saliva brakes down bacteria
Cellular defences
White blood cells fight infection as well as being found in the blood they can be found in other tissues and organs
Phagocytes which surround and eat pathogens then brake them down.
Examples neutrophils and macrophages
Natural killer cells
Natural killer cells
Found in the blood and lymph
Attack cancer cells and viruses
They release chemicals call performs which make holes in the cells leading it to die.
This inflammatory response helps to prevent spread of toxic agents other tissues, disk poses of pathogens and dead tissues cells, promotes tissue repair and attracts immune cells to the site of damage.
Natural killer cell inflammatory response
Signs are Redness, heat, swelling and pain
Occurs after physical trauma, intense heat, chemical damage and infection.
Range of chemicals are released. E.g histamine increases blood supply and increases permeability of capillaries, allowing leukocytes to damage tissue.
Causes swelling, causing protein rich fluid to be released. Help form clots and scabs
Helps repair and healing
What is a neutrophils
Phyagosite
White blood cell that Eats pathogens. Then die.
Form of puss
First to respond
