Ch 3/4 Flashcards
What is histology?
Study of structure and composition of skin tissue
Histology is essential for understanding the organization of skin layers and their functions.
What does physiology study?
Study of the functions of living organisms
Physiology relates to how skin functions in overall health.
Who is an esthetician?
Specialist in cleansing, beautification, and preservation of the skin on the entire body
Estheticians play a key role in skincare and beauty treatments.
What are the appendages of the skin?
- Hair
- Oil glands
- Nails
- Sweat glands
These appendages contribute to skin health and functionality.
What characteristics define healthy skin?
Soft, smooth, slightly moist, and somewhat acidic
Healthy skin maintains a balanced pH and moisture level.
Which part of the body has the most sensitive nerves?
Fingertips
Fingertips are critical for tactile sensitivity.
What does TEWL stand for?
Transepidermal water loss
TEWL indicates the skin’s barrier function and hydration status.
What happens when the barrier function is damaged?
Results in really dry or dehydrated skin
A compromised barrier can lead to increased TEWL.
What are melanocytes?
Cells that produce pigment and protect the body from UV rays
Everyone has the same number of melanocytes regardless of skin color.
What do melanosomes produce?
Melanin
Melanin is responsible for skin pigmentation.
List the layers of the skin from outermost to innermost.
- Epidermis
- Dermis
- Hypodermis (subcutaneous layer)
Each layer has distinct functions and structures.
What is the composition of the hypodermis?
80% fat, thins with age
The hypodermis provides insulation and cushioning.
What is the papillary layer?
Thinner layer of the dermis, contains collagen and elastin
It supplies skin with oxygen and nutrients.
What is the reticular layer?
25% thicker than the epidermis, made of collagen and elastin
This layer provides strength and elasticity to the skin.
What does the dermis contain that is beneficial for the skin?
Contains hyaluronic acid
Hyaluronic acid helps retain moisture in the skin.
What is the stratum corneum also known as?
Horny cells
Cell turnover happens here.
What is the function of the stratum lucidum?
Forms fingerprints; thickest on palms and soles of feet
Also known as clear cells.
What are stratum granulosum cells filled with?
Keratin that resembles granules
It replaces cells shed from the stratum corneum.
What is the largest layer of the skin?
Stratum spinosum
Also known as the spiny layer.
What is the stratum germinativum known for?
Growth layer (mitosis)
This layer is responsible for the production of new skin cells.
What are the two types of melanin?
- Eumelanin
- Pheomelanin
Eumelanin is dark brown to black, while pheomelanin is red to yellow.
What is the role of brightening agents?
Suppress melanin production
These agents are used in skin care to reduce pigmentation.
What percentage of hair is keratin B?
90%
Keratin A is soft, while keratin B is hard.
When do nails grow faster?
During summer
Growth rates can be influenced by environmental factors.
