Anatomy chapter 5
2 types of cutaneous membrane
- Epidermis- outer (or most superficial) part of the skin - Dermis- Just underneath (or deep to) the epidermis
Function of skin
- Protects tissues and organs - Excretes salts, water, and organic waste (glands) - Maintains body temperature - Synthesizes vitamin D3 - Stores lipids - Detects touch, pressure, pain, and temperature
2 kinds of melanin
- eumelanin- black or brown - pheomelanin - reddish
subcutaneous layer functions
- protection - Energy reservoir - thermal insulation
What are the strate layers of the epidermis from superficial to deep?
- stratum corneum - stratum lucidum - stratum granulosm - stratum spinosum - stratum basale
how many layers of skin can the epidermis have?
4 thin skin or 5 thick skin layers called starta
Extending from the hair follicle to dermal papillae are muscles called
Arrector pili
what structures originate in the dermis and extend through the epidermis?
Hairs, nails, and glands
The subcutaneous layer is also known as the _____ or superficial fascia
Hypodermis
gray hair results from the gradual reduction of ______ production
Melanin
merocrine and apocrine sweat glands use ______ cells to release their accumulated secretions
Myoepithelial
sebaceous glands produce an _____ material that coats hair shafts and the epidermal surface.
Oily
Skin color can be influenced by
blood supply to skin, oxygen level in blood, other blood pigments, lack of melanin
the 3 recognizable zones along the length of a hair are
bulb, root, shaft
The root and shaft of a hair consist of _____ epithelial cells, while the hair bulb contains _____ epithelial cells
dead, living
the dermal papillae interlock with deep projections of the epidermis called
epidermal ridges
Hypodermis
loose connective tissue (adipose, areolar)
what does skin color and pigment depend on?
melanin and carotene
the color of hair is the result of
melanin production
What cells makes up melanin
melanocytes, protects nuclei of keratinocytes from UV radiation
the 2 types of sweat glands in the skin are ______ sweat glands and ______ sweat glands
merocrine, apocrine
The nail plate covers a layer of epidermis that is called the
nail bed
What 2 types of connective tissue does the dermis have
papillary layer (areolar tissue) and reticular layer (dense irregular tissue)
A type of gland associated with a hair follicle is usually a _____ gland
sebaceous
the secretions of sebaceous glands, called ______ is usually deposited into a ______
sebum, hair follicle
the secretion from merocrine sweat glands are carried to the surface of the epidermis via ______. the secretion of the epidermis sweat glands are carried into
sweat ducts/hair follocles
The skin houses 2 types of general exocrine glands, which are ______ glands and _______ glands
sweat, sebaceous
Carotene
yellow/ orange pigment found in some red, yellow, orange veggies