BSC 2085 Exam 2
What are Decubitus ulcers? - ✔️✔️-bedsores caused by problems with dermal
circulation
-Caused by compression of superficial blood vessels
-Sores most common on skin covering joints or bony prominences
-Affects epidermis and dermis: Kills epithelial cells (easier for bacteria to invade) and
Erodes dermal tissues
What is the Stratum Basale? - ✔️✔️-Is attached to basement membrane by
hemidesmosomes
-Forms a strong bond between epidermis and dermis
-Forms epidermal ridges (basis of fingerprints)
-Dermal papillae (tiny mounds)- projections from the dermis-Increase the area of
basement membrane and ttrengthen attachment between epidermis and dermis
-Has many basal cells, or germinative cells
Describe the Cutaneous Membrane - ✔️✔️consist of two components:
Outer epidermis
Superficial epithelium (epithelial tissues)
Inner dermis
Connective tissues
What Systems are connected to the Integumentary system? - ✔️✔️Cardiovascular
system- By blood vessels in the dermis
Nervous system- By sensory receptors that detect stimuli for pain, touch, and
temperature
How many parts makeup the integumentary system? - ✔️✔️The integument is made
up of two parts
1. Cutaneous membrane (skin)
2. Accessory structures
Accessory Structure - ✔️✔️Originate in the dermis
Extend through the epidermis to skin surface. Includes:
Hair, Nails, Multicellular exocrine glands
Is the hypodermis part of the Integumentary system? - ✔️✔️No, Located below the
dermis
-Composed of loose connective tissue: separates integument from the deep fascia
around organs
- Location of hypodermic injections
,5 main functions of the Integumentary System? - ✔️✔️1. Protection of underlying
tissues and organs
2. Excretion of salts, water, and organic wastes (glands)
3. Maintenance of body temperature (insulation and evaporation)
4. Production of melanin, keratin, vitamin D3, and storage of lipids
5. Detection of touch, pressure, pain, and temperature
PEMPD
Describe the Epidermis - ✔️✔️Is avascular stratified squamous epithelium
Nutrients and oxygen diffuse from capillaries in the dermis
Dominated by keratinocytes (most abundant type of epithelial cells) -contain large
amounts of the protein keratin
Thin skin: location and layers - ✔️✔️Covers most of the body
Has four layers of keratinocytes
Thick skin: location and layers - ✔️✔️Covers the palms of the hands and soles of the
feet
Has five layers of keratinocytes
What are the 5 strata of keratinocytes in thick skin - ✔️✔️1. Stratum basale
2. Stratum spinosum
3.Stratum granulosum
4. Stratum lucidum (missing in thin skin)
5.Stratum corneum
Bottom to top
Integumentary System- weight and area - ✔️✔️Is the largest system of the body
16% of body weight
1.5 to 2 m2 in area
What determines fingerprints? - ✔️✔️Determined by genetics and
uterine environment during fetal development.
Do identical twins have the same fingerprints? - ✔️✔️No
What are specialized cells of Stratum Basale? - ✔️✔️1. Merkel cells- specialized
epithelial tactile cells
Found in hairless skin
Respond to touch (trigger nervous system)
2. Melanocytes
Contain the pigment melanin
Scattered throughout stratum basale
, What is the Stratum Spinosum? - ✔️✔️"the "spiny layer"
-Produced by division of stratum basale
-Eight to ten layers of keratinocytes bound by desmosomes
-Cells shrink until cytoskeletons stick out (looks spiny) - under normal histological
preperations
-Continue to divide, increasing thickness of epithelium
-Contain dendritic (Langerhans) cells, active in immune response - defend against
microorganisms that get past superficial layers of epidermis and defend against
superficial skin cancers
Describe the Stratum Lucidum - ✔️✔️the "clear layer"
-Found only in thick skin
-Covers stratum granulosum
-Cells here are flattened, densely packed with keratin and are devoid of organelles
Stratum Cornuem - ✔️✔️-the "horn layer" (latin cornu=horn)
-Exposed surface of skin (15 to 30 layers of keratinized cells) lasts about 2 weeks
-Water resistant, not water proof!
-Shed and replaced every two weeks
-All exposed skin surfaces (except the anterior of the eyes) undergo cornification
(keratinization) - formation of protective, superficial layers of cells filled with keratin
Cells of Stratum Granulosum - ✔️✔️-Produce protein fibers
-Dehydrate and die (organelles disintegrate)
-Create tightly interlocked layer of keratin surrounded by keratohyalin
-Keratohylain cross links keratin and dehydrates cell
Keratinization - ✔️✔️-The formation of a layer of dead, protective cells filled with
keratin
Occurs on all exposed skin surfaces except eyes
What is the skin life cycle? - ✔️✔️Skin life cycle
-It takes 7 to 10 days for a cell to move from stratum basale to stratum corneum
-Once there, cells may remain at stratum corneum for an additional 2 weeks before
shedding off
Two types of perspiration - ✔️✔️Insensible and sensible
What is Insensible perspiration - ✔️✔️-Interstitial fluid lost by evaporation through the
stratum corneum
-Lose approx. 500mL or 1 pint of H2O per day
What is sensible perspiration? - ✔️✔️Water excreted by sweat glands
What are Decubitus ulcers? - ✔️✔️-bedsores caused by problems with dermal
circulation
-Caused by compression of superficial blood vessels
-Sores most common on skin covering joints or bony prominences
-Affects epidermis and dermis: Kills epithelial cells (easier for bacteria to invade) and
Erodes dermal tissues
What is the Stratum Basale? - ✔️✔️-Is attached to basement membrane by
hemidesmosomes
-Forms a strong bond between epidermis and dermis
-Forms epidermal ridges (basis of fingerprints)
-Dermal papillae (tiny mounds)- projections from the dermis-Increase the area of
basement membrane and ttrengthen attachment between epidermis and dermis
-Has many basal cells, or germinative cells
Describe the Cutaneous Membrane - ✔️✔️consist of two components:
Outer epidermis
Superficial epithelium (epithelial tissues)
Inner dermis
Connective tissues
What Systems are connected to the Integumentary system? - ✔️✔️Cardiovascular
system- By blood vessels in the dermis
Nervous system- By sensory receptors that detect stimuli for pain, touch, and
temperature
How many parts makeup the integumentary system? - ✔️✔️The integument is made
up of two parts
1. Cutaneous membrane (skin)
2. Accessory structures
Accessory Structure - ✔️✔️Originate in the dermis
Extend through the epidermis to skin surface. Includes:
Hair, Nails, Multicellular exocrine glands
Is the hypodermis part of the Integumentary system? - ✔️✔️No, Located below the
dermis
-Composed of loose connective tissue: separates integument from the deep fascia
around organs
- Location of hypodermic injections
,5 main functions of the Integumentary System? - ✔️✔️1. Protection of underlying
tissues and organs
2. Excretion of salts, water, and organic wastes (glands)
3. Maintenance of body temperature (insulation and evaporation)
4. Production of melanin, keratin, vitamin D3, and storage of lipids
5. Detection of touch, pressure, pain, and temperature
PEMPD
Describe the Epidermis - ✔️✔️Is avascular stratified squamous epithelium
Nutrients and oxygen diffuse from capillaries in the dermis
Dominated by keratinocytes (most abundant type of epithelial cells) -contain large
amounts of the protein keratin
Thin skin: location and layers - ✔️✔️Covers most of the body
Has four layers of keratinocytes
Thick skin: location and layers - ✔️✔️Covers the palms of the hands and soles of the
feet
Has five layers of keratinocytes
What are the 5 strata of keratinocytes in thick skin - ✔️✔️1. Stratum basale
2. Stratum spinosum
3.Stratum granulosum
4. Stratum lucidum (missing in thin skin)
5.Stratum corneum
Bottom to top
Integumentary System- weight and area - ✔️✔️Is the largest system of the body
16% of body weight
1.5 to 2 m2 in area
What determines fingerprints? - ✔️✔️Determined by genetics and
uterine environment during fetal development.
Do identical twins have the same fingerprints? - ✔️✔️No
What are specialized cells of Stratum Basale? - ✔️✔️1. Merkel cells- specialized
epithelial tactile cells
Found in hairless skin
Respond to touch (trigger nervous system)
2. Melanocytes
Contain the pigment melanin
Scattered throughout stratum basale
, What is the Stratum Spinosum? - ✔️✔️"the "spiny layer"
-Produced by division of stratum basale
-Eight to ten layers of keratinocytes bound by desmosomes
-Cells shrink until cytoskeletons stick out (looks spiny) - under normal histological
preperations
-Continue to divide, increasing thickness of epithelium
-Contain dendritic (Langerhans) cells, active in immune response - defend against
microorganisms that get past superficial layers of epidermis and defend against
superficial skin cancers
Describe the Stratum Lucidum - ✔️✔️the "clear layer"
-Found only in thick skin
-Covers stratum granulosum
-Cells here are flattened, densely packed with keratin and are devoid of organelles
Stratum Cornuem - ✔️✔️-the "horn layer" (latin cornu=horn)
-Exposed surface of skin (15 to 30 layers of keratinized cells) lasts about 2 weeks
-Water resistant, not water proof!
-Shed and replaced every two weeks
-All exposed skin surfaces (except the anterior of the eyes) undergo cornification
(keratinization) - formation of protective, superficial layers of cells filled with keratin
Cells of Stratum Granulosum - ✔️✔️-Produce protein fibers
-Dehydrate and die (organelles disintegrate)
-Create tightly interlocked layer of keratin surrounded by keratohyalin
-Keratohylain cross links keratin and dehydrates cell
Keratinization - ✔️✔️-The formation of a layer of dead, protective cells filled with
keratin
Occurs on all exposed skin surfaces except eyes
What is the skin life cycle? - ✔️✔️Skin life cycle
-It takes 7 to 10 days for a cell to move from stratum basale to stratum corneum
-Once there, cells may remain at stratum corneum for an additional 2 weeks before
shedding off
Two types of perspiration - ✔️✔️Insensible and sensible
What is Insensible perspiration - ✔️✔️-Interstitial fluid lost by evaporation through the
stratum corneum
-Lose approx. 500mL or 1 pint of H2O per day
What is sensible perspiration? - ✔️✔️Water excreted by sweat glands
