The Skin Lecture Flashcards
What are the 3 epidermal derivatives?
Hair, nails and glands
The skin is also called the…
cutaneous membrane
The cutaneous membrane/skin is composed of what three layers?
The epidermis, dermis and hypodermis
The thickness of skin is dependent on the thickness of the …
epidermis
T or F
Most of our skin is thick
F
Only the palms of our hands and the soles of our feet are considered thick
What parts of the skin are thick?
The palms of the hand and soles of the feet
T or F
Thin skin usually has hair, thick skin never does
T
The epidermis is a multi layered epithelium consisting primarily of …
keratinocytes.
The epidermis is classified as a s… s… epithelium
stratified squamous
What layer of the skin acts as a protective barrier?
The epidermis
Why does the epidermis provide protection against viruses?
Viruses need to invade a nucleus to duplicate, grow and live. Since the outer layer of the epidermis consists of dead keratinocytes, which have no nucleus or organelles, viruses cannot invade the surface.
The epidermis has distinct layers that represent different stages of…
cell maturation
What are the 5 layers of the epidermis?
Stratum granulosum
Stratum spinosum
Stratum basale
Stratum lucidum
Stratum corneum
What is the deepest layer of the epidermis?
The stratum basale
Which layer of the epidermis is “prickly”?
The stratum spinosum
Which layer of the epidermis contains daughter cells from basale?
The stratum spinosum
Which layer of the epidermis contains a single layer of cells?
The stratum basale
Which layer of the epidermis contains stem cells for regeneration
of the epidermis?
Stratum basale
Which layer of the epidermis is the granular layer?
Granular layer
What functions do the granules in the stratum granulosum perform?
Keratin formation and water resistance
The stratum … is a sub-division of the stratum corneum.
lucidum
Which layer of the epidermis is clear?
The stratum lucidum
Which layer of the epidermis has cells that lack nucleui and organelles?
The stratum corneum
Which layer of the epidermis is filled with keratin filaments?
The stratum corneum
Which layer of the epidermis has a cell membrane that can become thickened?
The stratum corneum
Which layer of the epidermis is coated with lipids to form a water resistant barrier?
The stratum corneum
T or F
Keratinocytes mature over time
T
Stem cells divide in
which layer of the epidermis?
The stratum basale
What is the purpose of melanin?
It protects DNA from UV radiation
T or F
Melanin degrades and must be replaced
T
Melanin is packed into vesicles called …
melanosomes.
Melanin is transferred into …
keratinocytes
The dermis is comprised of what two layers?
The papillary and reticular layers
T or F
Within the dermis, the papillary layer is closest to the hypodermis whilst the reticular layer is closest to the epidermis?
F
vice versa
The papillary layer of the dermis is made up of…
loose connective tissue
The reticular layer of the dermis is made up of..
Dense irregular connective
tissue
T or F
Fibres in the papillary layer of the dermis have a smaller diameter than the reticular layer
T
T or F
The papillary layer of the dermis contains sensory nerve endings
T
T or F
The papillary layer of the dermis does not contain capillaries
F
T or F
The epidermis is avascular
T
The papillary layer of the dermis forms … that interlock with epidermal ridges
dermal papillae
What is the purpose of the dermal papillae?
Strengthens attachment between epidermis and dermis
Which layer of the dermis am I?
I am a meshwork of thick collagen and elastic fibres. I contain blood vessels, nerves, hair follicles and glands
The reticular layer
What 3 functions does subcutaneous tissue have?
– Protection/padding
– Energy reservoir
– Insulation
The hypodermis holds … to underlying tissue & permits … of skin
integument
movement
Hair is located everywhere except…
on the palms, soles, lips & portions of external genitalia
Internally, hair is surrounded by a sheath made of…
connective tissue
Hair is a living/non-living structure produced in
hair follicles
non-living
Hair growth starts at the…
hair bulb
Hair papilla is … tissue containing ….
connective
blood vessels
T or F
During the production of hair, epithelial cells divide & push downwards
F
upwards
What smooth muscle is attached to hair follicles and responsible for goose bumps?
Arrector pili
…. are sensory nerves that sense hair movement
Root hair plexus
