Skin- FOM Flashcards
What are the functions of skin?
- Protection
- Thermoregulation
- Excretion of sweat
- Vit D synthesis
- Sensory reception
What are the functions of the gut?
- Ingestion, propulsion and secretion
- Mechanical digestion
- Chemical digestion
- Absorption
- Defecation
Describe the structure of the gut tube (outward to inward)
- Serosa
- Muscular externa (longitudinal muscle, circular muscle)
- Submucosa
- Mucosa (muscular mucosa, lamina propria, epithelium)
- Lumen
What are the three layers of the skin?
- Epidermis
- Dermis
- Hypodermis
Classify the epithelium found in the epidermis
Stratified squamous keratinised epithelium
What are the 5 layers of the epidermis?
- Stratum basale
- Stratum spinosum
- Stratum granulosum
- Stratum lucidum
- Stratum corneum
(keratin formed at surface)
What are the 2 layers of the dermis?
- Papillary layer- dermal papillae (loose CT)
- Reticular layer- dense irregular CT, connects skin to hypodermis
Describe the hypodermis
- Subcutaneous
- Primarily adipose tissue
- Segregated by loose CT
- Insulation and energy storage
- Major vessels/nerves
Describe the epidermis
- Origin of skin appendages
- Keratohyalin granules kill cell
Describe the stratum basale
Stem cell layer where cell division takes place
Describe the stratum spinosum
Prickle cell layer
Describe the stratum granulosum
Where keratohyalin granules are found
Describe the stratum lucidum
Shine any only found in thicker skin
Describe stratum corneum
Horny layer
What are other cells found in the epidermis?
- Keratinocytes
- Melanocytes
- Merkel’s cells (mechanoreceptors in basal layer)
- Langerhan’s cells (phagocytic cells in spinous and granulosum)
What are skin appendages?
Develop from epidermis and extend to dermis and hypodermis
Describe a hair follicle and hair bulb
- Down growth from epidermis
- Terminal dilation with matrix cells
- Attachment of erector pili muscle also keratinised outgrowth
Describe sweat glands
- Eccrine, apocrine
- Areola, axilla, anal and genital
Describe sebaceous glands
- Produce waterproof sebum
- Associated with hair follicles
Describe nails
- Nail plate- compacted dead cells
- Nail bed- dermis, epidermis, vessels and nerves
Describe non-encapsulated sensory nerve endings
Epidermis between keratinocytes or attached to Merkel cells to detect pain/heat.
Dermis- around hair follicles to detect hair displacement
Describe encapsulated sensory nerve endings
Pacinian corpuscles (pressure) and Meissner’s corpuscles (light touch)
Describe motor nerve endings
Sympathetic motor efferent nerve endings supply
Vascular smooth muscle, erector pilli muscles and sweat glands
