1/26/2016 erector musc Structure of Hair shaft Structure and Function of the Skin human skin Perspiration provides moisture and nutrients for bacterial growth Two parts: Dermis -Contains salt that inhibits microorganisms Epidermis -Contains lysozyme that breaks down bacterial cell walls Passage-ways for -Contains antimicrobial peptides ens: Sebum a mixture of lipids,proteins and salts is nd ducts secreted by oil glands to prevent skin and hair from drying out -Contains fatty acids that inhibit microbes -Contains nutrients for their growth as well aticn) Mucous Membranes Mucous Membranes Line the body cavities open to the exterior Mucus Tightjunctions ‘mam妆icells -Cells secrete mucus Some cells have cilia Often acidic,which limits the microbial Epithelial cell population Normal flora produce fatty acids from sebum Membrane of tied together by Often folded to maximize surface area1/26/2016 2 Hair follicle Oil gland (produces sebum) Hair erector muscle Hair shaft Stratum corneum Sweat pore Epidermis Structure of human skin Two parts: Dermis Keratin Epidermis Dermis Epidermis Passage-ways for pathogens: Hair follicles Oil gland ducts Subcutaneous layer Duct of sweat gland Sweat gland (produces perspiration) Blood vessels Nerve Adipose tissue (fat) Oil gland ducts Sweat gland ducts Structure and Function of the Skin • Perspiration provides moisture and nutrients for bacterial growth – Contains salt that inhibits microorganisms – Contains lysozyme that breaks down bacterial cell walls – Contains antimicrobial peptides • Sebum a mixture of lipids, proteins and salts is secreted byg p oil glands to prevent skin and hair from drying out – Contains fatty acids that inhibit microbes – Contains nutrients for their growth as well Mucous Membranes • Line the body cavities open to the exterior • Tightly packed epithelial cells attached to an extracellular matrix – Cells secrete mucus – Some cells have cilia • Often acidic, which limits the microbial population - N rm l fl r pr duce f tt cids fr m sebum Normal flora produce fatty acids from sebum • Membrane of eyes washed by tears containing lysozyme, which destroys cell walls of certain bacteria • Often folded to maximize surface area Mucous Membranes