Exam 2 SG Integument (pt1) Flashcards
Name the accessory structures of the skin
- Nail
- Hair
- Muscles
- Nerves
- Various Glands
What are the two principal parts of the skin?
Epidermis and Dermis
What is the makeup of the hypodermis?
Areolar and Adipose tissue
What are the functions of the skin?
- Thermoregulation
- Protection from environment
- Cutaneous sensation
- Excretion
- Synthesize of vitamin D
- Reservoir for blood
- Absorbs substances
What are the types of cells in the epidermis?
- Keratinocytes
- Melanocytes
- Langerhans cells
- Merkel cells
Describe Keratinocytes
90% of the epidermis, provides the hard waterproof protection of skin
Describe Melanocytes
Comprised of mealnosomes which produces the pigment melanin; Melanin also provides protection from UV light
Describe Langerhans cells
- The immune cell, originates from red bone marrow
- Migrates to the epidermis and lymphoid tissue to initiate the immune response as an APC (dendritic cell)
Describe Merkel cells
The least numerous cell in the epidermis; Combined with tactile discs it functions in the sensation of touch
What is the most common type of cell in the epidermis?
Keratinocytes
What is the least common type of cell in the epidermis?
Merkel cells
Describe Stratum Corneum
- Most superficial layer filled with 25 - 30 layers of keratinized cells.
- Between cells, lipids from lamellar granules provide water proofing
Describe Stratum Lucidum
Deep to the stratum corneum, only found on thick skin
Describe Stratum Spinosum
Deep to stratum granulosom, filled with 8 – 10 layers of keratinocytes and a few langerhans cells. Cells are still alive
Describe Stratum Basale
deepest layer of the epidermis, filled mostly with keratinocytes (continuously undergoing mitosis) and has few melanocytes and merkel cells
Describe Stratum Granulosom
Deep to the stratum lucidum filled with 3-5 layers of keratinocytes and the transition between live and dead cells
Name the epidermal layer that is named after its artifactual appearance
Stratum spinousm
Name the epidermal layer that is undergoing apoptosis
Stratum granulosm
Name the epidermal layer that is where keratin begins to form
Stratum basale
Where is thick skin located?
Fingertips, palms of hands, and soles of feet
List the different types of sensory structures found in the skin
- Merkel cells and tactile discs
- Meissner corpuscles and free nerve endings
- Pacinian corpuscles
Where are Merkel cells and tactile discs found?
stratum basale
Where are Meissner corpuscles and free nerve endings found?
papillary region of the dermis
Where are Pacinian corpuscles found?
subcutaneous layer
