Derm physiology Flashcards
What are the 5 layers of the epidermis
Can’t Leave Germany Sad Boy
Stratum corneum
Stratum lucidium
Stratum Granulosim
Stratum Spinosum
Stratum basale
What type of epithelium is the epidermis
Stratified keratinised squamous epithelium
Which layer of the epidermis is only present in areas of think skin e.g. sole of foot
Stratum lucidium
What is the stratum cornuem mainly made up of
Dead keratinocytes
Which layer of the epidermis is where keratinocytes are enveloped by hard proteins and where they begin to die
Stratum granulosum
Which layer of the epidermis contains desmosomes that connect the layers of keratinocytes
Stratum spinosum
Which layer of the epidermis contains dendritic cells and releases FFAs
Stratum spinosum
What is the only vascularised layer of the epidermis that contains actively dividing keratinocytes
Statrum basale
Which layer of the epidermis contains melanocytes and tactile cells
Stratum basale
Which layers of the epidermis contains the following cells:
a) dendritic cells
b) desmosomes
c) melanocytes
d) tactile cells
a & b -> stratum spinosum
c & d -> stratum basale
Why is it that the stratum corneum contains dead keratinocytes
As the keratinocytes gradually die as they move up the layers as they lose their blood supply
What type of cell found in the stratum basale detetcs light-touch sensation and are mechanoreceptors
Tactile cells
What type of cell found in the stratum basale produces melanin
Melanocytes
Which type of cell found in the stratum spinosum is involved in the immune response
Dendritic cells
Which layer of the epidermis releases FFAs
Stratum spinosum
What are the 3 stages of the hair cycle
Anagen -> Catagen -> Telogen
ACT
Which stage of the hair cycle is where most hairs are present (80->90%)
Anagen
Which stage of the hair cycle is where hair gradually stops growing
Catagen
Which stage of the hair cycle is where hair stops growing, and is replaced by new hair
Telogen
What stage of the hair cycle is known as the resting phase
Telogen
Give 4 examples of skin adnexa
Hair
Nails
Glands
Sensory sturctures
Lable the diagram of a nail
Red -> hyponychium
Yellow -> nail bed
Green -> Lunula
Blue -> cuticle
Purple -> mantle
What types of temperatures do peripheral and central thermoreceptors detect
Peripheral -> environmental temp
Central -> core body temp
Where are peripheral theroreceptors located
Skin
Face
Scrotum
Where are central thermoreceptors located
Spinal cord
Abdominal organs
Hypthalamus
Give 7 functions of the skin
Thermoregulation
Immune protection
Barrier from pathogens
Water-proofing
Sensation
Vit. D synthesis
Interperonsel communication
What symptom occurs as a result of the body’s mechanism for fighting infection
FEVER
What type of cells cause fever by trigeering the release of prostaglandins from the hypothalamus
Endogenous pyogenes (IL-1 & IL-6)
What are the 2 endogenous pyogenes that cause fever
IL-1 & IL-6
What are the symptoms of a bite from a black widdow…
Intense pain
Profuse sweating
Difficulty in breathing
Loss of consciousness
Violent convulsions
(and finally…)
Death
What are the 3 layers of skin (from superficial to deep)
Epidermis -> Dermis -> Hypodermis
What are the 2 layers of the dermis
Papillary layer
Reticular layer (deepest)
What type of glands surround hair follicles and offer lubrication
Sebaceous glands
What layer of the dermis contains derma papillae which are responsible for finger prints
Papillary layer
Which of the 3 layers of skin maintains tempeatrue homeostasis
Hypodermis
What type of glands are sweat glands
Exocrine glands
What is the differnece between thick and thin skin in terms of the number of layers
Thin -> 4 layers
Thick -> 5 layers (have a stratum lucidium)
What vasomotor responses occur in response to…
a) cold stress
b) heat stress
a) arteriolar constriction
b) arteriolar dilation
Give examples of processes that increase heat generation in the body
General metabolism
Voluntary muscular activity (moving about)
Involuntary muscular activity (shivering)
Non-shivering thermogenesis (buring brown fat in infants)
What is the aim of the body’s response to cold stress
Increase body temp
What is the aim of the body’s response to heat stress
Decrease body temp
What processes decrease heat loss from the body
Vasomotor control -> arteriolar constriction
Behavioural responses -> putting on clothes, moving to warmer areas
A body tempeature below what thershold is diagnostic of hypothermia
<35oC
Who are most at risk of hypothermia
folk who are cold
what gene is mutated that causes ginger hair
MCR-1
