Which layer of the epidermis is only found in the palms and soles of the feet?
Stratum lucidum
The stratum lucidum is a thin, clear layer of dead skin cells in the epidermis.
Name the layers of the skin from bottom to top.
- Hypodermis
- Dermis
- Epidermis
The hypodermis is not technically a layer of skin but is included for completeness.
What pigment protects skin from UV radiation?
Melanin
Melanin is produced in the melanocytes found in the epidermis.
Where is this pigment produced?
In the melanocytes
Melanocytes are located in the basal layer of the epidermis.
Name 4 functions of skin.
- Protection
- Sensation
- Thermoregulation
- Metabolism of Vitamin D
The skin plays a crucial role in maintaining homeostasis and protecting the body.
Dermal papillae found between the epidermis and dermis form what commonly known feature?
Fingerprints
Fingerprints are unique patterns formed by the dermal papillae.
What are the 2 major layers of the dermis?
- Papillary layer
- Reticular layer
The papillary layer is the upper layer of the dermis, while the reticular layer is the thicker, deeper layer.
How does their structure differ?
The papillary layer is thin and contains loose connective tissue, while the reticular layer is thicker and consists of dense irregular connective tissue
This structural difference contributes to the varying functions and properties of each layer.
In which layer of the skin would a basal cell carcinoma begin?
Epidermis
Basal cell carcinoma originates in the basal cells of the epidermis.
You have just run 1 mile and your face is red. Explain why.
Increased blood flow to the skin for thermoregulation
The body increases blood flow to the skin to dissipate heat generated during exercise.
A sudoriferous gland produces ___________.
Sweat
Sudoriferous glands are responsible for producing sweat to help regulate body temperature.
Which type of sudoriferous glands are known to cause body odor?
Apocrine glands
Apocrine glands are primarily found in areas such as the armpits and groin.
Your neighbor is about to have knee surgery. Will the surgeon cut vertically or horizontally for the surgical incision? Why?
Horizontally to minimize scarring
Surgical incisions are often made parallel to the skin’s natural lines to reduce visible scarring.
The portion of the hair that sticks out of the skin is the hair _______, while the portion within the skin is the hair _______.
Shaft, root
The shaft is the visible part of the hair, while the root is embedded in the follicle.
What occurs at the hair bulb?
Hair growth
The hair bulb is the structure at the base of the hair follicle where cell division occurs, leading to hair growth.
What is the function of sebum?
Moisturizes and protects the skin
Sebum is an oily substance produced by sebaceous glands that helps keep skin and hair hydrated.
Name 3 functions of hair on the body.
- Insulation
- Protection
- Sensory reception
Hair serves multiple purposes including regulating body temperature and providing sensory feedback.
You use your fingernails to pick up a thread from the table. What portion of the nail did you use?
Nail plate
The nail plate is the hard, visible part of the nail.
Three nail structures can be found within this small area. Name them.
- Nail matrix
- Nail bed
- Lunula
These structures are essential for nail growth and health.
What internal portion of the nail is the site of nail formation?
Nail matrix
The nail matrix is located beneath the base of the nail and is responsible for producing new nail cells.
You just got a chill and your arm hairs are raised. Why?
Piloerection due to cold or emotional response
Piloerection is the contraction of the arrector pili muscles, causing hair to stand up.
