Lecture 2 Material (Integumentary System) Flashcards
What are the 3 Layers of the skin?
1) Epidermis (top)
2) Dermis (middle)
3) Subcutaneous layer/Hypodermis (bottom)
Accessory structures of the skin (glands, hair, hair follicles, etc.) are part of WHICH layer of the skin?
The Dermis.
Which layer of the skin has the arteries and veins?
The Subcutaneous Layer/Hypodermis
What are the two layers of the Dermis?
The Papillary layer and the Reticular layer
On the topic of sweat glands, where does the oil come from?
The oil comes from the sebaceous gland which is ALWAYS associated with a hair follicle
What is the name of another structure that is associated with a hair follicle? (It also causes goosebumps)
Arrector pili muscle
What are the 4 cell types in the Epidermis layer of the skin?
1) Keratinocytes
2) Melanocytes
3) Tactile cells
4) Dendritic cells
What layers is the Epidermis made out of?
Stratified Squamous Epithelium
How many layers are there in the Epidermis?
- It depends what type of skin it is. In thin skin there are 4 layers.
- In thick skin there are 5 layers.
Where on our body do we have thick skin? Where do we have thin skin?
We have thick skin on the soles of our feet and the palms of our hands. Everywhere else, we have thin skin.
Why is the palms of our hands or soles of our feet lighter or “shiny”?
Because it contains the stratum lucidum (which is a layer thick skin has and thin skin doesn’t)
What is Keratin? What does it do?
- Keratin is a hard protein seen in the skin and hair
- Keratins keep some moisture out and in our body to protect the skin
a) What do Melanocytes do?
b) Where are they found?
a) Melanocytes produce melanosomes, which are a type of lysosome that produces and stores melanin (a skin pigment)
b) They are found in the Basal layer, the Basal lamina
a) What do Tactile cells do?
b) Where are they found?
a) The Tactile epithelial cells function as sensory receptors and stimulate sensory nerves that result in your sense of touch
b) They are found in the stratum basale
a) What are epidermal Dendritic cells and what is their function?
b) How do they carry out their function?
a) Epidermal dendritic cells are immune cells that serve as a defense against potentially infectious microorganisms on the skin
b) They carry out phagocytosis of pathogens that infiltrate the more superficial layers of the epidermis (i.e. closer to the surface)
Where are Dendritic cells located?
They are most prominently located in the superficial portion of the Stratum spinosum
What layer has the blood supply?
The Basal lamina.
a) Where do the keratinocyte cells start to die in the epidermis?
b) Why does it happen there (how does it happen)?
a) They start to die in the Stratum granulosum.
b) - Because the keratinocytes are pushed up through the stratum granulosum and (in thick skin) the stratum lucidum.
- As the cells move further towards the superficial layer of the epidermis, a protein found in cytoplasmic granules of the keratinocytes called keratohyalin forms granules that dehydrate the cell and causes them to die as they get bigger and flatter coming closer to the surface.
What does bluish colour from the blood supply in the Dermis lead to?
Cyanosis
a) What does the papillary layer consist of?
b) What does the reticular layer consist of?
a) Loose connective tissue and blood supply
b) Sensory structures and collagen
What is sebum and what produces it?
Sebum is a waxy, oily secretion produced by the sebaceous glands and follicles