(M) Lab: Skin Flashcards
Layer of the Epidermis:
- consists of a single layer of basophilic columnar/cuboidal cells
- has INTENSE mitotic activity
Stratum Basale
These cells are clear and are found in the basal layer with dark nuclei
Melanocytes
Layer of the Epidermis:
- is the THICKEST layer
- consists of polyhedral cells that synthesize keratin filaments (tonofibrils) that converge and terminate at the desmosomes
Stratum Spinosum
These are keratin filaments that converge and terminate at the desmosomes in the Stratum Spinosum
Tonofibrils
These are known as the INTERCELLULAR bridges found in the Stratum Spinosum
Desmosomes (cell to cell adhesion)
Layer of the Epidermis:
- consists of 3-5 layers of flat polygonal cells
- their cytoplasms are filled with keratohyaline granules which are basophilic
Stratum Granulosum
T or F: The columnar/cuboidal cells of the Stratum Basale are eosinophilic
False (basophilic hence dark-staining)
T or F: The keratohyaline granules of the Stratum Granulosum are eosinophilic
False (basophilic hence dark-staining)
T or F: The Stratum Lucidum is only found in thin skin
False (thick)
*Think: The thicker the skin, the more layers it has
Layer of the Epidermis:
- found only in thick skin
- consists of a translucent layer of flat eosinophilic cells
Stratum Lucidum
What layers consist of basophilic cells/cytoplasm?
- Stratum Basale - the columnar/cuboidal cells
- Stratum Granulosum - the keratohyaline granules (IN THE CYTOPLASM)
The basophilic cytoplasm contents in the Stratum Granulosum are called?
Keratohyaline granules
T or F: The Stratum Lucidum is composed of basophilic cells
False (eosinophilic)
Keratinocytes in the Stratum Lucidum are densely packed with keratin precursors known as?
Eleidin
Layers of the Epidermis:
- consists of 15-20 flat non-nucleated cells that are CONTINUOUSLY shed
Stratum Corneum
T or F: The Stratum Corneum is shed PERIODICALLY
False (continuously)
What is it called when surface cells continuously flake off?
Exfoliate or Slough off
T or F: The Stratum Corneum is prominent in thin skin
False (thick; palms, soles, and corresponding fingers and toes)
What is the fundamental tissue type of the papillary layer of the dermis?
Connective
What is the fundamental tissue type of the reticular layer of the dermis?
Connective
What is the subtype of the papillary layer of the dermis?
Connective Tissue Proper
What is the subtype of the reticular layer of the dermis?
Connective Tissue Proper
T or F: The papillary layer of the dermis is also known as the dermis proper
False (reticular)
What is the specific subtype of the papillary layer of the dermis?
Loose Connective Tissue
What is the specific subtype of the reticular layer of the dermis?
Dense Irregular Connective Tissue
This is found in the papillary layer of the dermis and its function is detection of fine touch
Meissner’s Corpuscles
T or F: The Meissner’s Corpuscles are found in the reticular layer of the dermis
False (papillary)
The pilosebaceous unit is composed of what 2 parts?
- Hair follicle
- Sebaceous glands
What is the nature/type of secretion of sweat glands?
Serous
What is the mechanism of release of sweat glands?
Merocrine
What is the morphology of sweat glands?
Simple Coiled Tubular
What is the nature/type of secretion of sebaceous glands?
Mucous
What is the mechanism of release of sebaceous glands?
Holocrine
What is the morphology of sebaceous glands?
Simple Branched Acinar
What layers are found in thin skin?
Basale, Spinosum, Granulosum, and Corneum
Thin skin is found on the entire body except?
Palms and soles
Hair follicles are present in thin skin EXCEPT?
- Lips
- Labia minora (vagina)
- Glans penis
Where is the location of thin skin?
Everywhere except the palms and soles
Where is the location of thick skin?
Palms and soles
What epidermal layer is ABSENT in thin skin?
Stratum Lucidum
T or F: The dermal appendages for thick skin include sweat glands, sebaceous glands, hair follicles, and the arrector muscles
False (THIN)
T or F: Thick skin has sebaceous glands
False (only thin skin since it has hair)
T or F: Sweat glands are only found in thick skin
False (found on both)
T or F: Sweat glands are found on both skin types while sebaceous glands are only found in thin skin
True
How many epidermal layers does thin skin have?
Only 4