Non-Specific responses to diseases AS Biology Unit 2 OCR

Primary Defence: Are those that attempt to prevent pathogens from entering the body

The Skin:
Main primary defence
Outer layer called the epidermis - consists of a layer of cells
Most of these cells are called Kerationcytes
They are produced by mitosis
As they move & dry out cytoplasm is replaced by protein keratin
When the cells reach the surface they are not alive - the keratinisised dead layer of cells acts as an affective barrier to pathogens

Mucous Membranes
02 & nutrients must enter our blood
Leaves body exposed to infection as barrier between blood and environment reduced

Areas protected by mucous membranes
Epithelial layer contains mucus-secreting cells called goblet cells
Mucus lines passages and traps pathogens
Epithelium…