chapter 6 skin and membranes part 2 Flashcards
Dermal-epidermal junction
Gluelike layer between the dermis and epidermis
Soft hair of fetus and newborn is called
lanugo
Hair root lies hidden in follicle and visible part of hair is called
shaft
Hair growth requires epidermal tubelike structure called
hair follicle
Arrector pili is specialized smooth muscle that produces
“goose bumps” and causes hair to stand up straight.
Skin receptors
relay messages to the brain concerning sensations like touch, pain, and pressure.
Two skin receptors are
Lamellar corpuscle (Pacini corpuscle)Tactile corpuscle (Meissner corpuscle)
Tactile corpuscle (Meissner corpuscle):
Capable of detecting light touch
Lamellar corpuscle (Pacini corpuscle):
Capable of detecting pressure, which detects pressure deep in the dermis.
Skin glands include
The skin glands include the two varieties of sweat glands(sudoriferous) and the tiny sebaceous gland
Types of sweat or sudoriferous glands
Eccrine and Apocrine
Eccrine sweat glands
Produce perspiration or sweat, which flows out through pores on skin surface. Sweat assists in the elimination of waste products
Pinpoint-size openings on the skin are called
pores
Apocrine sweat glands are found in
Found primarily in the skin in the axilla (armpit) and in the pigmented skin areas around the genitals.
Sebaceous glands
Sebaceous glands secrete oil for the hair and skin.Grow where hairs grow
skin Protection; first line of defense against
Infection by microbes•Ultraviolet rays from sun•Harmful chemicals•Cuts and tears
Temperature regulation
Mechanisms of temperature regulation •Regulation of sweat secretion•Regulation of flow of blood close to the body surface
Functions of the skin
Sense organ activity,Excretion,Synthesis of vitamin D
Sense organ activity
-The skin’s millions of nerve endings serve as antennas or receivers for the body.
Excretion
body gets rid of waste
Synthesis of vitamin D
Occurs when skin is exposed to ultraviolet light
The upper region, or papillary layer, of the dermis is characterized by parallel rows of tiny bumps called
dermal papillae.
Subcutaneous tissue is also called
the superficial fascia or hypodermis
Nails are classified as
sensory organs
Crescent-shaped area nearest root is called
lunula
Under the nail lies a layer of epithelium called the
nail bed
Squamous cell carcinoma
Common type of skin cancerSlow growingLesions begin as painless, hard, raised nodules
Basal cell carcinoma
Most common type of skin cancerOriginates in cells at base of epidermis, often on upper face
Malignant melanoma
Most serious form of skin cancerMay develop from benign, pigmented moles or excess UV radiation
Kaposi sarcoma (KS)
Caused by Kaposi sarcoma–associated herpes virus (KSHV), also known as human herpes virus 8 (HHV8).
abcde stands for
asymmetry, border, color, diameter, involving
