Term 1 Exam: Chapter 5 Integumentary System (from slides) Flashcards
What are the organs of the integumentary system?
The skin and its accessory structures including hair, nails, and glands as well as blood vessels, muscles and nerves
What are some common skin diseases?
Skin cancer Viral infections such as chicken pox or measles
What is another name for the skin?
Cutaneous Membrane
What are 6 functions of the Skin?
- Temp regulation 2. Blood reservoir 3. Protection from external environnment 4. Cutaneous sensations (touch, pressure, vibrations) nerve endings 5. Excretion: (urea and ammonia) and aborption (vit D) 6. Synthesis of Vitamin D
What is the structure of the skin?
Skin consists of two layers: 1. epidermis - Outer, thinner layer that consists of epithelial tissue 2. Dermis - Inner, thicker layer that consists of connective tissue
What is the subcutaneous layer (SubQ layer)?
Lies beneath the dermis Attaches the skin to the underlying tissues and organs
What forms the integument?
Skin and subQ layer
Label 1; 2; 3; 4
- Epidermis
- Dermis
- Subcutaneous layer
- Sebaceous (oil) gland
The Skin contains 4 principle types of cells what are they?
- Keratinocytes (~90%) 2. Melanocytes (~8%) 3. Langerhans cells (aka intraepidermal macrophage cells) 4. Merkel cells
What are keratinocytes?
skin cells that produce keratin and lamellar granules to provide a waterproof environment for skin
What are Melanocytes?
Produce melanin pigments that protect against UV
What are Langerhans Cells
Involved in immune response
What are Merkel Cells?
Skin cells that function in the sensation of touch along with the adjacent tactile (Merkel) discs
How many layers does thin skin have? What are they from deepest?
4 1. Stratum Basale 2. Stratum Spinosum 3. Stratum Granulosum 4. Stratum Corneum
How many layers does Thick Skin have? What are they (from deepest)?
5 1. Stratum Basale 2. Stratum Spinosum 3. Stratum granulosum 4. Stratum Lucidum ( only in fingertips, palms and soles) 5. Stratum Corneum
What are 6 features of the stratum basale?
- Deepest layer where continuous cell division occurs (produces all the other layers) 2. Where stem cells are located 3. Composed of a single row of cuboidal or columnar keratinocytes 4. Nuclei of keratinocytes are large with abundant ribosomes, a small golgi complex and few mitochondria 5. Presence of keratin intermediate filaments (aka tonofilaments) protects deeper layers from injury 6. Melanocytes and Merkel cells are found in this layer
What are 4 features of the Stratum Spinosum?
- 8-10 layers of keratinocytes from the stem cells 2. Cells are rounder and larger, but flatten at more superficial layers 3. Bundles of tonofilaments insert into desmosomes 4. Layer also contain projections from intraepidermal macrophages (langerhans cells) and melanocytes
What are four features of the Stratum Granulosum?
- 3-5 layers of flattened keratinocytes 2. Keratinocytes contain keratohyalin and lamellar granules 3. Keratohyalin converts keratin intermediate filaments into keratin 4. Lamellar granules release lipid-rich water repellent - prevents loss of body fluids and entry of foreign materials
What are three features of the Stratum Lucidum?
- Present only in THICK skin (fingertips, palms, soles) 2. 4-6 layers of clear, flat, dead keratinocytes with large amount of keratin and thickened plasma membrane 3. Keratin arranged parallel to skin surface - provides an additional level of toughness
What are three features of the Stratum Corneum?
- Surface layer 2. 23-50 rows of dead, flat keratinocytes called corneocytes or squames (scale) - continuously shed and replaced by cells from deeper strata 3. Constant friction to the skin cases formation of a callus (abnormal thickening of the corneum)
ADD IMAGES
LABEL
What are two important characteristics of the Dermis?
- Composed of Connective Tissue 2. Contains Collagen and elastic fibres
What are the two layers of the Dermis?
- Papillary region 2. Reticular Region
What are 2 features of the Papillary region of the dermis?
- Most Superficial layer (represent 1/5 of thickness of dermis) 2. Consists of areolar connective tissue with thin collagen and elastic fibres