Integumentary System Flashcards
Epidermis
Outermost protective layer of the skin
Composed of keratinocytes, melanocytes and Langerhan’s cells
Thin layer, 0.1-1.5 mm thick
Dermis
Located beneath epidermis
Contains connective tissue, blood vessels, nerves, sebaceous glands, sweat glands and hair follicles
Thicker layer, 1-4 mm thick
Hypodermis (subcutaneous)
Deepest layer
Consists of loose connective tissue, fat cells and larger blood vessels
Thickest layer but varies in thickness to provide cushioning and energy storage
keratinocytes
Cells that produce keratin
Found in epidermis
melanocyte
Cells that produce melanin
Found in epidermis
Collagen
Most abundant protein in the body
Primary building block of skin, muscles, bones, tendons, ligaments and other connective tissues
Elastin
Stretchy protein that is responsible for the elasticity of tissues and organs
Sebaceous Glands
Organs in the skin that produce sebum, an oily substance that lubricates and protects the skin
Eccrine Sweat Glands
Glands that open directly onto the skin’s surface
Located all over the body
Apocrine Sweat Glands
Glands that open into a hair follicle
Located in armpits and groin
Stratum Corneum
Outermost layer of skin
Contains dead skill cells that protect the skin from UV radiation, heat, pathogens and abrasions (scrapes)
Stratum Lucidum
Second outermost layer of skin
Provide extra protection for palms of hands and soles of feet
Stratum Granulosum
Middle layer of skin
Forms the waterproof barrier and prevents fluid loss from the body
Stratum Spinosum
Second innermost layer of skin
Made of several layers of skin held together by desmosomes (sticky proteins that look like spines)
Stratum Basale
Most inner layer of epidermis
One cell thick
Hair
Made of keratin
Provides protection for skin, increases sensory function and assists in temperature regulation
Arrector Pili
Tiny muscles within hair follicles that pull on the hair causing it to stand up or erect
Nails
Made of Keratin
Provides protection for the sensitive tips of the fingers and toes
Hair Follicle
Produces and supports hair growth and anchors it to the skin
Located in the dermis
Hair Proper
Hair shaft that is visible beyond the skin, provides protection and sensory functions
Stratified Keratinocytes
Form the primary layer of epidermis
Produce keratin and aid in formation of protective barrier
Dermal Papilla/Ridges
Small extensions of dermis that increase surface area and contribute to the formation of fingerprints
Meissner’s Corpuscles
Detect light touch and vibration
Located in the dermis mainly on the fingertips and lips
Pacinian Corpuscles
Detect deep pressure and vibrations
Located deep in the dermis
Merkel’s Discs
Detect pressure and temperature
Located in the epidermis
Nociceptors
Pain receptors that detect tissue damage and send pain signals to the brain
Thermoreceptors
Detect changes in temperature and help regulate body temperature
Afferent Nerve
Carry sensory information AWAY from the body TOWARD the brain
Coiled Gland of Sudoriferous (Sweat) Gland
Produces sweat to regulate body temperature
Duct of Sudoriferous (Sweat) Gland
Transports sweat from gland to the surface of the skin
Dermal Arterioles
Regulate blood flow and contribute to temperature control
Small blood vessels in the dermis
Dermal Venules
Small veins in the dermis that return deoxygenated blood to the heart
Sebaceous Gland
Secretes sebum (oily substance) into hair follicles
provides protective barrier and prevents dryness
Sebum
An oily substance released from sebaceous glands that lubricates skin and hair
Arrector Pili Muscle
Tiny muscle attached to hair follicle that causes hair to stand upright
Creates goosebumps and aids with thermal regulation
Adipose Tissue
Stores energy in the form of fat provides insulation and cushioning
Found in subcutaneous layer
Stratum Basale
Provides the stem cells that make up the layers of the epidermis
Deepest layer of epidermis
Contains keratinocyte stem cells and melanocytes
Stratum Spinosum
Responsible for making skin flexible and strong
Located between stratum basale and stratum grandulosum
Contains keratinocytes and Langerhans cells
Stratum Granulosum
Forms the cell envelope of of cells in the stratum corneum and help form waterproof barrier that prevents fluid loss from the body
Granules within kerotinocytes are visible in this layer
Located between stratum spinosum and stratum lucidum
Stratum Lucidum
Reduce friction between stratum corneum and stratum granulosum
Only seen in thicker regions of skin such as the palms hands or soles of feet
Stratum Corneum
Most superficial layer of epidermis that sheds as new keratinocytes are made
Keratinocytes become corneocytes in this layer
Corneocytes
Strong, dead keratinocytes that protect the skin from harm/damage.
1st Degree Burn
Pain with tissue damage in the epidermis
2nd Degree Burn
Pain with tissue damage in epidermis and part of the dermis, nerves and blood vessels are intact
3rd Degree Burn
Numb or no pain, tissue damage in all three layers, blood vessels and nerves are destroyed, skin is white or blackened/charred
Irritant Contact Dermatitis
A non-allergic reaction of the skin when exposed to chemical or physical irritants that damage the protective layer of the skin
Deep Cut
Affects all three layers of the skin, allows pathogens to enter body causing an infection
Melanoma
Also known as skin cancer, uncontrolled division of cells
Usually presents as an abnormal mole on the body and is usually caused by spending excessive time outside
