L15-L16 Integument I and II Flashcards
1
Q
What things make up appendages?
A
Nails, claws, hair, sweat glands, sebaceous glands
2
Q
What are characteristics about the integument? (3)
A
- Largest organ
- Invests entire body
- Continuous with epithelial linings of mouth, anus ,urethra, ear & earlids
3
Q
What are the main functions of integument? (5)
A
- Barrier for protection
- Provides immunologic information
- Conveys sensory information
- Excretion of waste products
- Thermoregulation (blood flow, sweating/panting)
4
Q
What are the skin layers? (3)
A
- Epidermis
- Dermis
- Hypodermis
5
Q
What are the skin layers that the integument is made out of?*****
A
Epidermis + dermis and NOT hypodermis
6
Q
What is the hypodermis? (4)
A
-Loose connective tissue with fat
-Not a part of skin layers
-Fat storage
-Contains large blood vessels
= superficial fascia
7
Q
What is the rete apparatus?
A
Means by which epidermis and dermis are attached;
- Interdigitations of epidermal ridges & dermal ridges (papillae)
- Attach epidermis to dermis
8
Q
What are three characterstics of epidermis?
A
- Stratified squamous kertinized epithelium
- Avascular
- continuously renewed by mitosis (20-30 day cycle)
9
Q
Thick skin epidermis characteristics? (3)
A
- Glabrous, smooth, non-hairy
- All five layers of epidermis; 400-600 nanometers thick
- Lacks hair follicles/ sebaceous glands
10
Q
Where on the body is thick skin found? (few examples)
A
Palms, soles
11
Q
Characteristics of thin skin? (5)
A
- Hairy
- 3-4 layers of epidermis
- 75-150 nanometers thick
- Found on most of body
- Thin skin includes hair follicles, sebaceous and sweat glands
12
Q
What are arranged in layers of the epidermis?
A
Keratinocytes
13
Q
What are the layers and what are some random characteristics of them? (5 starting from bottom to top)
A
- Stratum basale: closest to dermis/blood vessels
- Stratum spinosum: can include many layers
- Stratum granulosum: always stains dark
- Stratum lucidum: pale
- Stratum corneum: most external layer
14
Q
As one is being born, all keratinocytes are being pushed up and eventually gets _________?
A
Sloughed off
15
Q
What is the stratum basale also known as? What are they constantly doing?
A
Stratum germanitivum- making new cells
16
Q
What are four characterstics of stratum basale?
A
- Basophilic cytoplasm
- Cells lie on basement membrane
- Actively diving cells (renewed every 15-30 days)
- Large nucleus w/ abundance free ribosomes
17
Q
What do the stratum basale produce?
A
Produce intermediate filaments (keratin) = tonofilaments
18
Q
What are stratum basale bundled into?
A
Tonofibrils in stratum basale and stratum spinosum
19
Q
What does the stratum basale contain?
A
Contain desmosomes (between cells) and hemidesmosomes (between cell & basal lamina)
20
Q
What is the stratum basale location?
A
Location of melanocytes, associated with skin color
21
Q
What is unique about skin color?**
A
Vertebrates “thing”**
22
Q
What is the stratum spinosum also called?
A
Prickle cell layer
23
Q
The prickle cell layer can also be______ ? *
A
Artifacts!
24
Q
What is unique about the stratum spinosum?
A
Cell layer adjacent to s. basale mitotically active
25
Stratum spinosum- what does the histology look like (describe)? (2)
- Cuboidal or slightly flattened cells with central nucleus
| - Cells bound together by filament-filled cytoplasmic spines & desmosomes
26
What are the Nodes of Bizzozero?**
Desmosomes in the stratum spinosum that appear as thickenings in the spines where they attach on adjacent cells ("spine-studded" appearance)
27
The stratum spinosum's cytoplasm contains?
Processes filled with numerous bundles of intermediate filaments (keratin) (=tonofibrils)
28
What is unique about the desmosomes in teh stratum spinosum?
They are sideways because of the artifacts or becoming squished as they move up
29
What kinds of cells do the stratum spinosum contain?
Langerhands cells, which is party of the immune system
30
What are 4 features of the stratum granulosum?
1. 3-5 layers cells
2. Last layer with nuclei
3. Lysosomal enzymes digest organelles
4. Named for 2 types of granules: keratohyalin and lamellar granules (=bodies)
31
What is significant about stratum granulosum?***(test q)
Last place we cells that are alive
32
What do the stratum granulosum contain?
Keratinocytes from the stratum spinosum that are flattening
33
What are the keratohyalin granules and what are they produced by?
Intensely basophilic and not surrounded by a membrane, produced by ribosomes
34
Keratohyalin grandules (K) are associated with __________ to help strengthen them
Tonofibrils Act
35
The Lamellar bodies in stratum granulosum do what three things? Where are they produced? ** (test q)
1. Lamellar bodies discharge a lipid-rich content
2. Acts to serve as a barrier of foreign materials
3. Water-proofs the skin- produced in the Golgi apparatus
36
What are two charactertics about stratum granulosum? (important to remember)
- Lamellar bodies
| - Adaptation to terrestrial life
37
Where is stratum lucidum "housed"?
Thick skin
38
What are three characteristics of stratum lucidum?
1. No nuclei or organelles
2. Contain densely packed keratin
3. Clear, thin eosinophilic layer of extremely flattened cells
39
What do the stratum corneum look like histologically?
15-20 layers of flattened, non-nucleated, keratinized cells with thick membranes and no organelles
40
What are 3 characteristics associated with stratum corneum? ***
1. More layers in thick skin
2. Deep layers: cells held together by desmosomes (as move up layers)
3. Superficial layers: cells lose desmosomes and undergo dequamation
41
The epidermis also contains _______.
Non-keratinocytes
42
What are the two non-keratinocytes (and what do they do) in the epidermis?
1. Melanocytes: partially responsible for skin color
| 2. Langerhans cells: work with the immune system
43
Where are the melanocytes and what is special about them?
Primary located in stratum basale and do not have desmosomes (they need to move and not be attached)
44
What are melanocytes?
1. Rounded cell bodies
| 2. Long, irregular extensions between cells of stratum basale & stratum spinosum
45
What is a fact about melanocytes (pigment/color)?
Number of melanocytes is same in all groups, but the amount and distribution of melanin varies
46
How does UV light play a role in melanocytes?
- Exposure increase size and activity of melanocytes
| - Total number of melanocytes can increase with prolonged exposure
47
What do the Langerhands cell look like?
Apostrophe
48
Where are Langerhands cells located?
Stratum spinosum
49
What do the Langerhans cell look like?
Irregularly-shaped nuclei
50
What color does the Langerhands cells stain?
Pale
51
Where do LAngerhands cell originate from?
Precursor cells in bone marrow
52
What do the Langerhans cells function as?
Antigen presenting cells
53
What do Langerhans cell NOT have?
Desmosomes
54
What are characteristics of the dermis? (5)
- Connective tissue layer deep to epidermis
- Separated from stratum basale by a basement membrane
- Vascularized
- Nourishes epidermis
- Ranges from .6 mm to 3mm
55
What are tension lines/ cleavage lines/ Langer lines? (3)
1. Pattern of distribution of Type I collage fibers
2. Determines tension and wrinkle lines in skin
3. Determines pace and nature of would healing
56
What are the two layers of the dermis?
1. Papillary layer
| 2. Reticular layer
57
What are characteristics of the papillary layer of the dermis? (4)
- Loose connective tissue
- Contains collagen fibers (Types I & III), elastic fibers, anchoring fibrils that extend from basal lamin into papillary layer
- Interdigitates with epidermis (separated by basement membrane)
- Rete apparatus
58
What is the reticular layer? (6)
- Dense irregular connective tissue
- NOT an abundance of reticular fibers
- Type I collage fibers w/ thick elastic fibers
- Smooth muscle (arrector pilli)
- Epidermally derived glands
- Hair follicles
59
What is hair?
Elongated keratinized structures derived from invaginations of epidermal epithelium
60
What are sebaceous glands? (3)
- Produce sebum (waxy texture)
- Located all over body (except palms, soles, side of feet)
- Most abundant on face, forehead, & scalp
61
What do sebaceous glands secrete?
1. Secretes sebum (cholesterol, triglycerides, and cell debris)
2. Iolocrine secretion (as a secretory cell matures, it dies and becomes part of the secretory product)
3. Holocrine secretion: destruction of the cell
62
What is acinus?
Acinus: basal layer of undifferentiated flattened epithelial cells resting on basal lamina
(Packed with lipid filled vacuoles)
63
What do sweat glands help with?
Temperature regulation
64
There are 2 types of sweat glands:
1. Eccrine sweat glands (temperature regulation)
| 2. Apocrine sweat glands (other functions too)
65
What are characteristics of eccrine sweat glands?
- Simple coiled tubular glands
| - Ducts open on skin surface (=sweat pores: not assoc with hairs)
66
What do the eccrine sweat glands look like?
Invaginations of epithelium into dermis/ hypodermis
67
Where are eccrine sweat glands located?
Species-specific (numerous on pams and soles)
68
What are merocrine secretions?*
Another name for Exocytosis, cells not damaged during secretion
69
Features of apocrine sweat glands?
- Open into canals of the hair follicles just superficial to the entry of the sebaceous gland ducts
- Contain pheromones at axilla: secrete milky product, odorless until metab by bacteria
70
What is the vitally important thing in non-human animals regarding the apocrin sweat gland?!
Sebaceous gland ducts
71
Apocrine sweat gland vs Eccrine sweat gland?
- Larger lumen than eccrine sweat glands
| - Secretory product stored in lumen
72
Merocrine mode of secretion, NOT _____
Apocrine
73
What two things is the integument composed of?W
Skin and appendanges
