Chapter 5 Flashcards
Integumentary System
macrophages
part of the body’s defenses
engulfs large pathogens or damaged cells
microphages
smaller phagocytic cells that engulf small pathogens or debris
adipocytes
- “fat cells”
- provides energy, storage, and cushion
- many connective tissues need the energy reserves
mesenchymal cells
cal ultimately differentiate into other needed connective tissue cells especially after an injury
melanocytes
produce the pigment melanin
mast cells
produces a histamine that stimulates inflammation and heparin which prevents blood from clotting.
Both are released after an injury or infection
lymphocytes
helps with body defense and may develop into plasma cells which produce antibodies
What are the steps of tissue repair?
- inflammation
- organization
3 regeneration and fibrosis
What types of tissues are highly regenerative?
- epithelial tissue
- bone tissue
- blood (made in red bone marrow)
- areolar connective tissue
What types of tissues are only slightly regenerative?
- cartilage (all types)
2. skeletal muscles
What types of tissues are nonregenerative?
- cardiac muscle
2. nervous tissue
What two regions make up the skin?
- epidermis - outermost layer - epithelial tissue
2. dermis - makes up majority of skin - vascuralized
keratinocytes
stratified squamous epithelial cells that produce the protein keratin
makes up majority of the epidermis
Langerhans’ cells
originate in the epidermis; act as macrophages
Merkel cells
found in the deepest layer of the epidermis; function as receptors to sense gentle light touch
What are the layers of the epidermis?
- Stratum Corneum
- Stratum Lucidem
- Stratum Granulosum
- Stratum Spinosum
- Stratum Basale
Stratum Basale
- stratum germinativum
- deepest layer of the epidermis
- Usually only 1-2 cells thick
- contains keratinocytes, melanocytes, and merkel cells
- layer has many cells that are actively dividing
stratum spinosum
- “prickly layer”
- cells of this layer have a spiny appearance
- several cell layers thick
- cells contain pre-keratin filaments
- contains majority of the melanin and Langerhans’ cells
stratum granulosum
- “granular layer”
- appears grainy and is only 3-5 cells thick
- keratinocytes in this layer contain lamellated granules (important for water proofing)
- last layer of epidermis where diffusion of nutrients and oxygen from the capillaries can reach the cells (outer 2 layers cells are dying or already dead)
stratum lucidum
- “clear layer”
- clear layer only few cells thick
- dying cells start to line up the keratin fibers parallel to one another
stratum corneum
- “horny layer”
- 20-30 cells thick
- acts as an overcoat to protect underlying layers
- cells are dead
What are the layers of the dermis?
- papillary layer
- reticular layer
papillary layer
mostly composed of areolar connective tissue and contains many capillaries and sensory neurons
reticular layer
makes up majority of dermis and is mostly composed of dense irregular connective tissue
What 3 pigments determine skin color?
melanin (only one made in skin)
corotene (obtained in diet)
hemoglobin (pinkish-red pigment)
melanin
- not everyones melanocytes produce the same amount of melanin
- If melanocytes do not produce any melanin the person is considered albino
- protects from UV rays
corotene
- obtained from carrots and summer squash
- stored in skin/adipose tissue
- piled up in sections of skin thicker than normal
- converted to vitamin A (used as maintenance of epithelial cells and to maintain photoreceptors in retina of eye)
hemoglobin
- pinkish-red pigment
- carries O2 in red blood cells
- vermillion- pink part of lips, lips have no melanin
Name some properties of light
- behaves both like a wave and a particle
- light energy pack into particles (photons)
- shorter the wavelength, the greater energy that particle carries
- UV radiation is part of the electromagnetic spectrum
Describe the cause of skin cancer
When light travels through cells undergoing mitosis, it disrupts the process. Dividing is then out of control or cells make bad copies which causes skin cancer
What does a tan alert us to?
A tan is the body’s alert system to get out of the sun
Why can skin cancer be transferred to other organs?
Because the skin is vascularized.
sebaceous gland
produces sebum (oil) which lubricates the skin and is bacteriacidal
sweat glands
sudoriferous glands produce sweat which allows for evaporative cooling
What is sweat made of?
mostly water, salts (NaCl), vitamin C, antibodies, lactic acid, and uric acid (from urea)
What are the 2 types of sweat glands?
- merocrine sweat glands
- apocrine sweat glands
merocrine sweat glands
we have this more and it is found on palms, soles, and forehead. Produces large amounts of water for evaporative cooling.
apocrine sweat glands
produces product that is partially water soluble. Found in public regions, axillary region, and hair follicles. Secretes sweat with all of the above and a lipid rich substance. This lipid substance lubricates the hairs to reduce chaffing and is energy rich that attracts bacteria to those regions
Name two specialized apocrine sweat glands
ceruminous glands and mammary glands
cerumenous glands
produces cerumen (ear wax) which lubricates and traps particles from entering the ear
mammary glands
modified sweat glands to form breast milk which is really rich in lipids
What is another name for hair?
philus (s)
phili (p)
What produces hair?
Hair is produced by hair follicles which are dead keratinized cells
What is the function of hair?
- protects against UV radiation
- prevents particles getting into openings
- protects against the glare from the sun
What is wrapped around the outside of the hair follicle?
The root plexus. These are nerves which sense hair vibrations
What causes hair to stand?
Arrector pili muscle
Name the types of hair.
vellus hair (found mostly on kids and female adults terminal hair (found on scalp, eyebrows, public, and axillary regions. thicker, courser, and has darker color. males can have ti on vace as it grows in response to testosterone.
Name conditions involving hair loss
- alopecia : gradual thinning that occurs as we age in both males and females
- male pattern baldness: true baldness
Burn
tissue damage caused by heat, electricity, radiation, or chemicals. This denatures cell proteins and kills the cell.
What are the categories of burns and what layers of the skin does it affect?
1st degree burn - epidermis
2nd degree burn - epidermis and upper dermis (blister)
3rd degree burn - destruction of epidermis and dermis
What issues are caused by burns?
loss of protection from fluid loss
Loss of protection against protection
What are the percentages for the rule of nines?
Arms - 4.5% each side Legs - 9% each side Head - 9% total Torso - 18% each side Genitals - 1%
What are the 3 forms of skin cancer from least dangerous to most dangerous?
- basal cell carcinoma
- squamous cell carcinoma
- melanoma
basal cell carcinoma
cells of the stratum basale grow/divide and invade into the dermis and hypodermis
squamous cell carcinoma
arises from keratinocytes of the stratum spinosum and more common on head and hands
melanoma
most dangerous type, occurs where ever there is pigment. Can metastasize rapidly to nearby blood and lymph vessels