and CORRECT Answers
Where are eyebrows located? - CORRECT ANSWER - Between the superior orbital rim
(margin) and superior nuchal line
What are the 5 layers of of the eyebrow? - CORRECT ANSWER - Skin, dense connective
tissue, muscle, loose connective tissue, and periosteum
What are the functions of the skin of eyebrow? - CORRECT ANSWER - Barrier to the
outside environment (prevents microbes from causing infections in underlying tissue)
What are the layers of the skin? - CORRECT ANSWER - epidermis, dermis, hypodermis
Outermost layer of skin - CORRECT ANSWER - epidermis
What cells compose the epidermis? - CORRECT ANSWER - Keratinocytes, melanocytes,
langerhans cells, merkel cells
What cell composes 90% of cells in epidermis? - CORRECT ANSWER - Keratinocytes
What is the function of keratinocytes? - CORRECT ANSWER - Produce the fibrous
protein keratin that provides structure and water-resistant properties
What are keratinocytes layers based on stages of differentiation? - CORRECT ANSWER -
-stratum basale (inner) - only layer where cells undergo mitosis
-stratum spinosum (next layer)
-stratum granulosum (3rd layer) - cells lose their nucleus and become flattened
-stratum corneum (outer)- dead, flattened cells filled with keratin where cells shed every few
weeks
, What is desquamation? - CORRECT ANSWER - Shedding off of dead skin cells
Cell within epidermis that produce melanin pigment - CORRECT ANSWER -
melanocytes
Why is melanin important for the epidermis layer? - CORRECT ANSWER - Filter UV
light to protect from DNA damage
What is the type of white blood cell found in epidermis? - CORRECT ANSWER -
Langerhans cells
Why are Langerhans cells important in the epidermis? - CORRECT ANSWER - Play a
role in immune response to protect against pathogens
What cells within the epidermis attach to nerve endings to form the "light touch" receptors? -
CORRECT ANSWER - Merkel cells
Why does the epidermis rely on the dermis for blood supply? - CORRECT ANSWER -
Epidermis is avascular
The epithelial cells are connected the the underlying dermis by: - CORRECT ANSWER -
basement membrane
Why is the basement membrane important? - CORRECT ANSWER - Serves as a partial
barrier allowing only water and small molecules to pass into the dermis
What is the dermis composed of? - CORRECT ANSWER - Connective tissue (fibroblasts,
collagenous fibers, elastic fibers, adhesive proteins, and ground substances), WBCs, adnexal
structures