lecture 30 Flashcards
what makes up the immune system
organs, cells and molecules
what does pathogen mean
a microbe which is disease causing
what are the primary lymphoid organs
bone marrow and the Thymus
whats a lymphocyte
a type of white blood cell in most vertebraes
what does the bone marrow act as
a source of stem cells which produce the innate and immune cells
what does the thymus act as
a school for the T cells, where they go and mature, learning to detect recognise viruses and pathogens, and also learn to not attack the body cells.
how many T cells make it through the thymus
about 10%
what are the secondary lymphoid organs
the spleen and the lymph nodes
what does the spleen act as
the site of initiation of response against blood borne bacteria
what do the lymph nodes act as
where the fluid of tissues and blood is filtered and immune response is initiated
what is lymph
fluid in the space between cells of the body
what does lymph do
it moves through lymphatic vessels, picking up debris and potential pathogens, showing these invaders to the lymph nodes
what are lymph nodes and where are they found
they are found along the lymphatic vessels, they collect and filter lymph fluid
what happens at the lymph nodes
this is where the adaptive immune response is initiated.
viruses are whatv
nucleic acid with protein code
what does a virus need to replicate
needs to invade body cells to inject their DNA code so the virus may be copied
epidermis contains what
dead cells, keratin and phagocytic immune cells
the dermis is what
thick layer of connective tissue, collagen and blood vessel and phagocytic immune cells
what immune cells are found in the skin
dendritic cells
dendrites do what
helps to alert the immune system something is going on
what are the chemical defence layers on the skin
defensins, lysozyme, sebum and salt
what are defensins and what do they do
defensins are little antimicrobial peptides on the skin that form holes in the cell membrane of pathogens.
whats lysozyme does it do
it functions to break down bacterial cell walls
whats Sebum and where does it come from
its a fluid on the skin that comes from sebaceous glands. Sebum lowers PH on skin which vreates hostile environment for pathogens
where does saltniness of skin come from, what does it do
this salt is from sweat glands and it creates a hypotonic environment. causing pathogen cells to lose water and lyse and die.
where are the goblet cells
they are within the epithelium of the mucosal membranes
what do goblet cells do
the produce the mucous that lines the mucous membranes.
where are mucosal membranes
on eyes, in trachea, in the gastrointestinal and urogential membrane
from the mucosiliary elevator, where does the mucous go?
goes up to the pharynx where the mucous is swallowed.
what are chemical defences about mucosal surfaces
Stomach – low pH
Gall bladder – bile
Intestine – digestive enzymes
Mucus-traps it
Defensins-like the skin ones
Lysozyme (tears, urine)-
what are the surfaces barriers of innate arm
the skin and mucosal layers
what are the internal defences of innate arm
phagocytes, naturall killer cells, inflammation, antimicrobal proteins, fever
what are the adaptive defences cells
T cells and B cells
b cells amke what
antibodies.
