Notes for Chapter 8: Skin
Athlete’s Foot: fungal infection of the skin
Bacteria: single celled organisms such as e. coli, salmonella, staphylococcus
Blood Vessels: Found in fat layer and dermis; transport nutrients, oxygen and waste
Cold Sores: viral infection of the skin
Colony: visible group of (millions) bacteria or fungi growing on agar.
Characteristic growth patterns, colors, shapes, etc. generally indicate different
species
Connective Tissue: fibers like collagen and elastin hold your skin in place and allow
it to stretch and snap back
Dermis: middle layer of the skin; contains receptors, glands, hair roots, blood
vessels, smooth muscle
Ducts: “tubes” that connect glands to pores at the skin surface
Epidermis: outermost layer of skin; provides protection from microorganisms, etc.
Does not contain any blood vessels
Two layers: living – bottom layer; produces cells that gradually move away
from blood supply to form the dead outer layer
Dead – outer layer; provides protection – dead cells are
constantly being shed, taking any microorganisms with them
Fat: Bottom layer of skin; provides insulation and energy reserve
Fungi: single-celled or multi-cellular; appear fuzzy or fibrous as colonies; fungal
infections include ringworm and athlete’s foot
Oil Glands: located in dermis along hair follicle; condition skin and hair
Pores: “holes” in surface of skin
Receptors: specialized nerve endings that receive information from the
environment: touch, temperature, etc.
Ringworm: fungal infection of the skin
Sweat Glands: located in dermis; produce sweat to cool you off and help rid the
body of wastes
Viruses: need to “live” inside of a host cell in order to reproduce; much smaller than
a cell – cannot be seen with a light microscope; cannot be cultured on agar; viral
skin infections include warts and cold sores
Warts: viral infection of the skin