Topic 9 Integumentary System Flashcards
(67 cards)
List the components of the integumentary system
Skin, Hair, nails, glands,
Sensory receptors (telling you about the world around you) and
Muscles
What are the different Skin layers
Epidermis (upper) = Superifical
Dermis (lower) = deep
Describe the epidermis of the skin, listing the five strata in order from deepest to most superifical
Epidermis of the skin is stratified squamous epithelium , avascular and it is separated into 4-5 strata (layers)
4-5 strata from deepest to superficial
1) stratum basale (2 cell types keratinocytes and melanocytes)
2) stratum spinosum
3) stratum granulosum
4) stratum lucidum
5) stratum corneum
Describe the structure of the five strata of the epidermis
Stratum basale: single row of cells (next to CT deepest layer of epithelial) - single row of cells
contains 2 cell types
1) keratinocytes (90%)
- undergo mitosis, make keratin (tough protein)
- migrate to surface as new cells are produced in basale
**2) melanocytes (10%) **
- produce pigment (melanin - for uv light protection)
- e.g against sunburns, wrinkles, collagen damage, cancer (DNA damage)
- skin colour: we all have the same relative number of melanocytes but cells produce diff amounts/shades of melanin (e.g freckles - melanin in eyes too
Albinism/achromia = no melanin - in areas of thin skin, blood (hemoglobin) from dermis is visible giving pinkish tinge - nail beds, lips
Stratum spinosum: limited cell division (look like they have spines = “spinosum”)
Stratum granulosum: contains dark-staining granules (very thin, really dark and skinny)
stratum lucidum: flat, dead cells ( grey appearance, too far from blood supply)
- only visible in thick skin
stratum corneum: 20-30 layers of flat,dead cells filled with keratin (tough protein), surrounded by waterproofing glycolipid (prevents water loss from leaking out)
- shed and replaced from below
What’s located in the dermis layer?
Contains blood vessels, nerves, glands, hair follicles
What is areolar CT (review question) what part of the integumentary system is this a part of?
A type of Loose connective tissue proper
* cells are fibroblast/fibrocytes
* Contains loosely arranged collagen and elastic fibres surrounded by a ground substance hyaluronic acid
* Highly vascular
This is a part of the papillary layer of the dermis
What is dense irregular CT (review question) where is this found in the integumentary system
A type of Dense CT
* it contains Collagen fibers arranged iregularly
* e.g dermis of skin
Found in the dermis of skin which is a part of the reticular layer (makes up most of the dermis)
What is adipose CT (review question)
Where is it found in the integumentary system?
A type of loose CT
- has very little matrix
cells are large adiposecytes which stores triglycerides (tissue look like chicken wire
- highly vascular
In skin this is a part of the hypodermis (aka superficial fascia, or subcutaneous layer)
- stores 1/2 of bodys adipose tissue used for insulation
What are the 2 sublayers of the dermis layer? name the tissues in these layers
2 sub layers CT from mesoderm
**1) Papillary layer **
- areolar CT
- Vascular
- Dermal papillae = has projections into the epidermis
- In thick skin, these form epidermal ridges (finger prints = imrpove grip)
**2) Reticular later **
- Most of dermis
- dense irregular CT (look at skin)
Hypodermis characteristics
Not part of the skin
Subcutaneous layer or Superficial fascia (any terms work)
Adipose CT below the skin
store 1/2 of body’s adipose tissue (acts as insulation) - layer of fat under skin
Stratum Basale
next to connective tissue and is the deepest layer of Epithelial which is a single row of cells
contain two cells, keratinocytes and melaninocytes
Keratinocytes
(90% of cells in layer, stratum basale)
A cell type thats a part of the stratum basale
Undergo mitosis
Make keratin (tough protein)
Migrate to surface as new cells produced in basale
Melanocytes
take up 10% of the layer, stratum basale
Produce pigment (melanin) (for uv light protection)
Explain the source of the colour of skin
Melanocytes (take up 10% of the layer, stratum basale)
produces pigment (melanin) for uv light protection
e.g against sunburns, wrinkles (collagen damage), and cancer (DNA damage)
- we all have the same relative number of melanocytes, but cells produce diff amounts/sahdes of melanin (e.g freckles or the melanin in our eyes)
What is Albinism/achromia?
no melanin
in areas of thin skin, blood (hemoglobin)
for demis it is visible giving pinkish tinge - nail beds, lips
Stratum spinosum
Limited cell dviision
Stratum granulosum
contains dark-staining granules
Stratum lucidum
Flat, deadells (too far from blood supply)
visible only in thick skin
Stratum corneum
20-30 layers of flat, dead cells filled with keratin (tough protein) surrounded by waterproofing glycolipid (prevents water loss)
Shed and replaced from below
What is located in the dermis and describe the two layers of the dermis
the dermis contains blood vessels, nerse, gland and hair follicles (THESE ARE JUST LOCATED HERE THEY ARE NOT THE DERMIS)
2 sublayers (Both are from CT and arise from the mesoderm)
1) papillary layer
- areolar CT
- vascular
- has projections into the epidermis = dermal papillae
- in thick skin, these form epidermal ridges = finger prints (improve grip)
2) reticular layer
- most of dermis
- dense irregular CT (look at skin e.g if stretched too much to quickly = stretch marks = little damage to reticular layer of dermis)
Papillary layer
Contains Areolar CT
vascular
has projections into the epidermis = Dermal papillae
Dermal papillae
A part of the papillary layer of the dermis
Dermal papillae are projections into the epidermis of the dermis
Epidermal ridges
- a part of the papillary layer of the dermis
contain dermal papillae (projections into the epidermis) and in thick skin these are finger prints (improve grip)
Reticular layer
Most of the dermis
dense irregular CT
look at skin ex) if stretched too much too quickly = stretch marks = little damage to reticular layer of dermis
