Immune System Flashcards
Tissue structure and function
What are B lymphocytes and role?
Features about them?
B-cells are involved in antibody-mediatrd immune response (humoral immunity)
B-cells fight pathogens by making antibodies for their antigens (lock and key)
This marks the pathogen so immune cells can destroy it
Present antigen to helper T-cells
Originate and mature in bone marrow
What are T lymphocytes and role?
Features about them?
Mature in thymus after its originate in bone marrow
Involved in cell mediated immunity
Roles Killing infected host cells Activiting other immune cells Producing cytokines Regulate immune response
What is cytokines and where it come from
It’s produced by T-cells and it’s a chemical message that activities other immune cells
What are cytotoxic T cells and role?
Type of T lymphocytes
Kill cells infected by pathogens and tumours
Release cytotoxic granules which kill cells
These require several signals from other cells to activate
What are helper t cells and their role?
Type of T lymphocytes
Help other immune cells
Activate other immune cells
Release cytokines
Helps b cells produce antibodies
What are memory t cells and their role?
Jump-start and immune response to and antigen, they detect it so natural killer T cells can protect the body
Natural killer T cells- innate deference against some pathogens
CD4+ plays a role in activation
CD8+ release the granules and kill infected cells
Then they move onto a new target
What are natural killer t cells and their role?
Kill infected cells and detecting and controlling early signs of cancer
Control several types of tumors and microbial infections limiting their spread and subsequent tissue damage
Often referred to as serial killing
What is Humoral immunity and what are its features?
Meditated by macromolecules found in extracellular body fluids is called humoral immunity e.g plasma
B cells are the main type of cell
Protects against extracellular pathogens and toxins
Antibodies are formed
Does not protect against cancer
What is cell meditated immunity and it’s features?
Identify cells that are affected Main type of cell is t cells Intracellular protection Antibodies are not formed Protects against cancer
What is the lymphatic system role?
It gets rid of dead cells and material
Drainage fluids
Transports clean fluid back to the blood
Drains excess fluid from tissues
Remove debris from cells of the body
Produces lymphocytes which protect the body against infections
Filters toxins, bacteria and harmful substances
What are the types of phagocytes?
Macrophages
Neutrophils/granulocytes
What is the role of macrophages and it’s features?
Second line of defence
Detect pathogens and destroys bacteria
Originate from monocytes, produced in the bone marrow
Circulate within almost every tissue patrolling for pathogens or eliminating dead cells
Long lifespan - months to years
What is the role of neutrophils/granulocytes and it’s features?
First cells to travel to the site of infection
They contain multi lobed nucleus
Ingesting pathogens
Release chemicals such as hydrogen peroxide to kill germs and clean up wounds
Short-lived - die after ingesting bacteria
Dead neutrophils make up a large population of pus
What are the types of immunity
Innate
adaptive
passive
What is innate immunity?
You are born with it and it’s general type of protection e.g skin
What is adaptive immunity?
It develops throughout our lives when we are exposed to diseases
Or immunized against them with vaccines
What is passive immunity?
Passive immunity is borrowed from another source and last a short time
E.g antibodies in mother’s breast milk give a baby temporary immunity to diseases
What is the first line of defence?
It is physical and chemical barriers E.g Skin tears saliva sweat mucus stomach acid
What is the second line of defence?
If a pathogen gets passed the first 1 and infection starts cells are phagocytes (macrophages and neutrophils)
It reacts to Inflammatory response
What are the signs of inflammation?
Redness pain heat swelling loss-of-function
What is the third line of defence?
Instead of being restricted to the site of infection the adaptive immune response occurs throughout the body
Cells are
B lymphocytes
t lymphocytes
What is the immune system?
The immune system is a complex network of cells and protects the body against infections
What is the functions of the immune system
To fight pathogens like bacteria and viruses parasites or fungus
To neutralise harmful substances e.g toxins
To fight disease causing changes in the body such as cancer cells
Recognise the difference between normal and foreign and keeps a record of the antigens/pathogens
What components make up the immune system
White blood cells antibodies lymphatic system spleen liver bone marrow appendix Adenoids Thymus Peyer's patches Tonsils
What is the function of the thymus gland in the immune system?
Produces progenitor cells which become t cells
The t cells will destroy infected or cancerous cells
What is the function of the spleen?
Filters your blood
Removes damaged red blood cells and stores iron
stores blood and releases it back into the system in an emergency
What is the function of the liver
Hepatocytes of the liver check blood and remove toxins
Breakdown old and damaged red blood cells
What is the function of adenoids?
Clusters of the lymphatic tissue in the back of the nose
It creates antibodies
Trap harmful substances
White blood cells circulate through the adenoids and other lymphoid tissue
What is a phagosome?
A phagosome is similar to lysosome, it is in white blood cells and is a vesicle formed around a microbe with digestive enzyme to break it down.
What is the shape of the nucleus in neutrophils?
multi-lobed 3 segments
What is the shape of the nucleus in macrophages?
Horse shoe shaped
What is the role of dendritic, also known as lymphocyte cells
Secretion of antibodies
Holds the antigen out to show B cells
What is the role of monocyte?
Monocyte is a special kind of stem cells in a way, they specialise into other types of white blood cells. Via phagocytosis
What are the types of agranulocytes?
Dendritic
Monocytes
What are the types of granulocytes
Neutrophils
Eosinophil
Basophil
What does granulocytes mean?
A cell that contains granules
What does esosinophil cells do?
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