Skin And Mucous Membranes Flashcards
Name the 6 functions of skin.
Protection
Thermoregulation
Water regulation
Sensation
Absorption
Store and synthesis - vitD, fat, glucose, water, salt
What are the 3 basic skin layers?
Epidermis
Dermis
Subcutaneous layer
Describe the structure of the epidermis?
Stratified squamous epithelium
Flat scale like cells
No blood vessels
4-5 layers
What is present on the surface of the skin?
A thick keratin layer
What is majority of the epidermis made up of?
What does it contain?
Stratum spinosum (prickle cell layer)
Contains desmosomes
What cell layer is only present in thick cells?
Stratum lucidum
Name the layers of epidermis. Outer to inner
Stratum corneum
Stratum granulosum
Stratum spinosum
Stratum basale
What is the stratum granulosum?
Cells become smaller and flatter due to there only being keratin and basic cell outline left
What makes up 95% of epidermal cells?
Keratinocytes (epithelial cells)
What are langerhans cells? (Present in epidermis)
Take antigens and present them to immune system
What do merkel cells do? (Present in epeidermis)
Sensory receptors
What do melanocytes do? (Present in epidermis)
Produce melanin
What cells are present in the epidermis?
Keratinocytes
Langerhans cells
Merkel cells
Melanocytes
Where does thick skin cover?
Palms of hands and soles of feet
Try to name the 9 things present in the dermis?
Fibroblasts
Macrophages
Few adipocytes
Nerve endings
Blood vessels
Glands
Smooth muscle (some areas)
Lymphatics
Hair follicles
What are fibroblasts?
Thin spindle shaped cells that produce collagen
What is the purpose of the papillary layer of the skin?
Holds epidermis and dermis together tightly
Where is the papillary layer of skin found?
Projects into intervals between epidermal ridges.
What is the papillary layer of skin supplied with?
Capillaries and nerve endings
What does the reticular layer of skin contain?
Dense connective tissues and fibre components
Name 5 causes of acne?
Change in hormones
Over production of sebrum
Infections
Diet
Smoking
Describe an example of an autoimmune condition that affects the skin?
Psoriasis
Primary skin is infected not mucous membranes
-rapid turnover of cells so thicker with more blood cells
From 10 to 7 days
Sign of psoriasis?
Inflammation causes red colour on skin
Describe pemphigus? An autoimmune condition that affects the skin.
One of the proteins that make up desmosomes and desmogein (protein) attach to antibodies and attack.
What does pemphigus look like in oral cavity?
Ruptures almost instantly
Painful raw areas in mouth
How to treat pemphigus? (Autoimmune skin condition)
Monoclonal antibodies
Describe vitiligo?
(Autoimmune skin condition)
Antibodies formed against melanocytes in basal layer or melanocyte stimulating hormone
Loss of pigment of skin
What are the 2 different types of skin cancer?
Basal cell carcinoma
Squamous call carcinoma
Describe a squamous cell carcinoma.
Overexposure to sunlight
Uncontrolled growth of epithelial cells
Keratinocytes in the epidermis grow out of control and form tumour
What type of skin cancer is slower in growth?
Basal cell carcinoma
Describe a malignant melanoma.
Most dangerous skin cancer
Caused by sun/sun beds
More likely to develop if moles present or runs in family
What is the first protective mechanism of the body in mouth?
Mucous membranes
What is a mucous membrane?
Epithelial lining that produces mucous containing mucosa (sticky protein) that traps microbes, pathogens, dirt etc
4 functions of the mucous membrane?
Protection
Secretion
Absorption
Sensation
How does the mucous membrane protect?
From trauma, pathogens etc
It protects underlying tissues in oral/nasal cavity and oesophagus
How does the mucous membrane secrete?
All mucous membranes contain some form of secretion
- in stomach it has a specific secretory function with production of acid and digestive enzymes.
How does the mucous membrane absorb?
Ability to absorb substances important for drug delivery
In GIT they absorb nutrients and water from intestinal contents
How does oral mucous membranes feel sensation?
has receptors for different types of sensation eg taste
Describe the basic structure of the mucous membrane?
2 layers
- epithelium
- lamina propria (mucosae)
Where are the layers of the lamina propria found?
Directly beneath the mucosal epithelium and it’s basement layers.
What is the epithelium layer in mucous membranes?
Stratified squamous and basement membranes
What is the lamina propria (mucosae) in the mucous membranes?
What does it contain?
Supportive areolar
Contains loose fibrous connective tissue and adipose tissue
What is the mucosa constituted of?
Lamina propria mucosae and epithelium
What cells does the lamina propria mucosae contain?
Fibroblasts
Immune cells
Lymph modules
Virtually lacking adipocytes
What extracellular matrix does the lamina propria mucosae contain?
Collagen
Elastin fibres
What is the trachea composed of?
Cillated, pseudostratified epithelium and an elastic, fibre rich lamina propria
What does the small intestine have affinity for?
Absorb material from small intestine epithelium
What enables small intestines to absorb?
Brush border
What do goblet cells produce?
Mucin
4 function of the oral mucosa?
Protection
Sensation
Secretion
Permeability and absorption
How does the oral mucosa protect?
Barred to micro organisms
How does the oral mucosa have sensation?
Receptors respond to touch, taste, pain etc
How does the oral mucosa secrete?
Maintain a moist surface with salivary glands.
How is the permeability and ability to absorb utilised in the oral mucosa?
Drug delivery
What type of epithelium is in the oral mucosa?
Stratified squamous
Describe the lining oral mucosa?
Buccal mucosa
Soft palate
Describe the masticatory oral mucosa?
Hard palate
What is the gustatory oral mucosa?
Tongue
Describe the nucleus in an oral mucosa? (2)
Parakeratosis = dark dots of nuclei remains
Orthokeratosis = pure, no nuclei
Is the oral mucosa keratinised or non keratinised ?
Can be both
What 2 types of conditions can be found in mucous membranes?
Acquired
Congenital
Give an example of a condition that affects the skin and mucous membrane.
Lichen planus
What does cystic fibrosis affect?
Epithelial lining of respiratory and GIT and reproductive tracts
- salivary glands
