skin & body membranes Flashcards
what does the integumentary system cover?
entire body
how many lbs is the integumentary system?
9 lbs
what percent of the integumentary system makes up the total body weight?
7%
in every sq cm the skin contains how many cm of blood vessels in the pinkie finger alone?
70 cm
in every sq cm the skin contains how many cm if nerves?
55 cm
how many sensory receptors are in the body?
230 sensory receptors
how many sweat glands are there in the integumentary system?
100
how many oil glands are in the integumentary system?
15
what is another term for oil glands?
sebaceous glands which waterproofs and protects the skin
how many cells are dying and constantly being replaced
1/2 million
what are the main 5 types of membranes found in the body?
- epithelial
- cutaneous
- mucous
- serous
- connective tissue membrane
is the epithelial membrane layer superficial or deep?
superficial, near the surface
what is the underlying deep layer of the epithelial membrane?
connective tissue
what is the cutaneous membrane also known as?
the skin
what are the 2 functions of the cutaneous membrane?
- protection
- keratinizing stratified squamous epithelium
what is the cutaneous membrane held down by?
dense irregular fibrous connective tissue
mucous membranes are the underlying what?
loose connective tissue
where is the mucous membrane located?
lining cavities that are open to the environment like the digestive and respiratory tracts
what are goblet cells and what membrane are they apart of?
goblet cells are apart of the mucous membrane and they secrete mucus to line the surface epithelial for protection
what 2 types of tissue make up 2 layers of the serous membrane?
- simple squamous
- areolar connective tissue
where is the serous fluid between in the serous membrane?
between parietal and visceral peritoneum
what 2 layers of tissue make up the serous membrane (scientific names) and why?
- parietal peritoneum
- visceral peritoneum
to decrease friction
where is the serous membrane found?
lining body cavities, specifically pericardial, abdominal, and pleural cavities
what are synovial membranes?
soft areolar connective tissue
does synovial/connective tissue have epithelial cells?
no
where is the synovial membrane ofund?
lining fibrous capsules surrounding the joints like shoulder and elbow
what are the 2 functions of the synovial/connective membrane?
- for smooth surface
- secrete synovial fluid to lubricate
what are the 4 types of damages the skin protects you from?
- mechanical
- chemical
- bacterial
- thermal
what are the remaining 6 things the skin protects you from (not including the 4 damages)?
- ultraviolet radiation
- desiccation
- heat loss
- heat retention
- excretion of urea & uric acid through sweat
- cholesterol molecules in skin convert vitamin D from sunlight
what is mechanical damage (the thing skin protects you from)?
pressure receptors alert nervous system from upcoming damaging movement and friction
what is chemical damage (the thing skin protects you from)?
stops chemicals from getting into underlying tissues by activating pain receptors to alert nervous system
what is bacterial damage (the thing skin protects you from)?
phagocytes ingest foreign substances and pathogens
what is ultraviolet radiation?
melanin made by melanocytes are for protection
what is thermal damage (the thing skin protects you from)?
heat, cold, and pain receptors
what is desiccation?
keratin in cells to reduce evaporation
what does heat loss do?
activates sweat glands to allow blood to go into skin capillaries
what are keratinocytes?
cells make keratin, a protein that makes the epidermis tough and protective
what is melanocytes?
make melanin, a pigment protecting DNA from UV light damage
what are dendritic cells?
alerts immune system of bacterial threat
what are merkel cells?
sensory nerve endings that are touch receptors
what type of tissue is the dermis made of?
connective tissue
what are the 3 made things found in the dermis?
- blood
- nerves
- lymph vessels
what are the cell types mostly found in the dermis?
- macrophages
- fibroblasts
what are the 2 major layers of the dermis?
- papillary
- reticualr
what are the 2 functions of the papillary layer of the dermis?
- connects epidermis to dermis
- is the place where finger and foot prints are found
what is in the papillary layer of the dermis?
blood vessels
what is the tissue type of the reticular layer of the dermis?
dense irregular connective tissue
what is the function of the reticular layer of the dermis?
for strength and flexibility, the dense irregular part gives flexibility
what is the percentage distribution for how much of the dermis reticular and papillary layer make up?
reticular: 80% of dermis
papillary: 20% of dermis
where is the reticular layer of the dermis most commonly found?
in cleavage lines where skin heals better if an incision is made along this area
what layer is found under the dermis?
hypodermis or subcutaneous layer
what is the subcutaneous layer made of?
adipose tissue, or fat
is the subcutaneous layer considered a skin layer?
no
what are the 5 functions of the hypodermis layer of the skin?
- stores energy
- body temp regulation
- protection
- hormone making
- cushioning
