5.1 The Skin and Subcutaneous Tissue Flashcards
dermatology
the study and treatment of the integumentary system
Functions of the skin
- resistance to trauma and infection
- barrier to water, UV rays, but permeable to lipid-soluble drugs
- Vitamin D synthesis
- Excretion of sweat
- sensation of heat, cold, touch, texture, pressure, vibration, tissue injury
- thermoregulation from thermoreceptors
- nonverbal communication like facial expressions
keratin
A tough protein formed by keratinocytes that constitutes the hair, nails, and stratum corneum of the epidermis.
Epidermis
- stratified squamous epithelium that constitutes the superficial layer of the skin, overlying the dermis
The Dermis
deeper layers of the skin, underlies the epidermis and composed of fibrous connective tissue
the dermis contains ___
- blood vessels, cutaneous glands, nerve endings
- hair follicles and nail roots embedded in dermis
- contains smooth muscles in association with hair follicles
dermal papilla
- A bump or ridge of dermis that extends upward to interdigitate with the epidermis, creating a wavy boundary that resists stress and slippage of the epidermis. (fig. 5.3)
- A projection of the dermis into the bulb of a hair, supplying blood to the hair. (fig. 5.8)
___ is what the dermis is mostly composed of
collagen
The dermis also contains
elastic and reticular fibers
- fibroblasts
- other fibrous connective tissue
- nervous tissue
- hyaline cartilage
The layer of areolar and adipose tissue lying beneath the dermis is called the ______.
hypodermis
the skin does NOT
produce vitamin E
Absorb nutrients
An alternate name for the hypodermis is the ______.
subcutaneous layer
Which of the following categories includes flexion creases, friction ridges, and patches of pigmentation?
Skin markings
Hair and nails are composed of______
dead, keratinized epidermal cells
An individual hair is also known as a(n) ______
pilus
The epidermis is composed of ______.
A thin filament of keratinized cells growing from a follicle is called a ______
a hair
Choose all of the following tissue types that are found in the dermal layer of the skin
connective tissue
nervous tissue
muscular tissue
epitheial tissue
Skin markings include
creases and friction ridges
compared to soft keratin, hard keratin is ___
is more compact and is toughened by numerous cross-linkages between the keratin molecules.
Hard keratin
hair does not
produce vitamin D
hair does
warm and insulate individuals
protect from UV
signal presence of small insects
The pilus (hair) grows within a structure called the ______
hair follicle
