Exam 2 Slide Show Integumentary (pt1) Flashcards
The skin consists of what two principal parts?
Epidermis and Dermis
What is the largest organ in the body in terms of external surface area and weight?
Skin
Which layer is the superficial thinner layer, composed of epithelial tissue?
The Epidermis
What is the branch of medicine that specializes in diagnosis and treatment of skin disorder?
Dermatology
Which layer is a deeper thick layer composed of dense irregular connective tissue?
Dermis
Which layer, consisting of areolar and adipose tissue, is not part of the skin?
The hypodermis (AKA subcutaneous layer)
What are the 7 specific functions of the skin?
- Thermoregulation
- Protection from external environment
- Cutaneous sensation
- Excretion
- Synthesis of vitamin D
- Reservoir for blood
- Absorbs substances
What are 3 ways thermoregulation effects the body?
- Evaporation of sweat cools the skin
- Increased blood flow to the skin promotes heat loss by radiation
- Hairs trap heat, thereby reducing heat loss in cold temperatures
What are melanocytes?
Pigment producing cells
In regards to the skin, what does it excrete?
Sweat which eliminates some water, salts, CO2, ammonia, and urea
The first step in activation of vitamin D begins in the skin by the action of what?
UV light
Keratinocytes make up how much of the epidermis?
90% of the cells and form 4 (or 5) layers
The epidermis is made up of which cells?
- Keratinocytes
- Melanocytes
- Langerhans cells
- Merkel cells
Which type of epithelium is the epidermis made of?
Kertatinized stratified squamous epithelium
What are langerhans cells known as?
Skin immune cells
What do merkel cells specialize in?
Skin sensation
What is the major cell type of the skin?
Keratinocytes
The melanosomes of melanocytes synthesize melanin from the amino acid _____
tyrosine
Which cell originates in the red bone marrow and migrates to the epidermis?
Langerhans cells
Which cell resides in the deepest layer of the epidermis where the contact the flattened processes of tactile discs?
Merkel Cells
Tactile discs are what?
A type of Sensory neurons
____ is the deepest layer of the epidermis
Stratum Basale
What are all the cells in the stratum basale?
Mostly keratinocytes, a few melanocytes and Merkel cells
The ________is present only where exposure to friction is greatest, such as the fingertips, palms, and soles
Stratum lucidum
Which is the least numerous cell of the epidermal cells?
Merkel cells
