Chapter 5: integumentary system

the subcutaneous layers function is to?

attach skin to underlying tissues or organs

the dermal papillae contain what 3 things?

capillaries free nerve endings Meissner corpuscle

freckles/moles are?

concentrations of melanin

Apocrine glands empty into hair ______, they are found in skin of axilla and _____, they function at beginning of ______

follicles groin puberty (prior to puberty, sweat is odourless, it is the bacteria on skin that produces the smell - kinds don't have to worry about being smell)

what layer do cells in epidermis begin to die?

granulosum

what are the 3 stage in hair growth?

growth regression resting

what are the 5 functions of skin?

1. protect body against dehydration, impact/frcition injuries, mold/bacteria invasion, UV light damage 2. receptor organs for sensory input 3. regulate body temperature 4. secrete waste 5. synthesize vitamin D

stratum corneum contains _____ layers of flat, dead keratinocytes, the ________ secretion acts as a _______ agent between cells, it is the layer we see and that interacts with the external environment, it protects us from friction by creating ______, it is eventually sheds off

25-30 lamellar waterproofing calluses

stratum granulosum contains ______ layers of flattened keratinocytes, _______: programmed cell death occurs, because they are ____ from blood supply, they contain what 2 cells

3-5 apoptosis far keratohyalin and lamellated granules

stratum lucidium contains ______ layers of clear, flat, dead keratinocytes, and is found in what kind of skin?

3-5 thick

skin accounts for what % of body weight

7

stratum spinsoum contains _______ layers of keratinocytes and contain ________ filaments, they are joined together by ________ and contain what 2 cells?

8-10 intermediate desmonsomes langerhan cells and melanocyte cells

hemoglobin is located in _______ and gives skin a ______ colour, as blood moves through _______

RBC pink capillaries

sebaceous glands are branched _____ glands connected to air follicles, they are activated by ______ hormone, they produce an oily substance _____, which softens and lubricates hair, to prevent ______ and inhibit growth of certain bacteria

alveolar androgen sebum dehydration

skin is an important indicator of what goes on in the body what are 3 conditions skin can let us know something is wrong?

anemic juandice edema

acne is a _______ inflammation of what glads?

bacterial sebaceous

which 2 layers of the epidermis contain living cells?

basal spinosum

special functions of the skin include (2)

body temperature regulation vitamin D synthesis

the hair ______ is at the base of the hair follicle, the hair _______ protrudes into the hair _____ and contains capillaries that provide blood, nutrients and gas exchange

bulb papilla bulb

vitamin D is important for absorption of ______ in the GIT?

calcium

what are two ways skin regulates body temperature?

capillaries (increase blood flow = bring heat, decrease blood flow = retain heat) sweat glands (evaporative cooling, helps skin cool, blood that is near skin brings down body temp)

vitamin d synthesis beings in skin with formation of precursors molecule _________, increasing in calcium from the food we eat

cholecalciferol

the skin synthesizes vitamin D from what molecules under action of sunlight?

cholesterol

stratum basale is the ______ layer and is attached to the ______ via wavy borders, it has _____ layer of columnar/cubodial __________, cells divide by _______

deepest dermis one keratinocytes mitosis

Cerminous glands (modified apocrine glands) are found in skin of the external ______ ____, they secrete a sticky _______ (cerum) which is a waterproofing agent and prevents foreign objects from entering

ear canal ear wax

composed of keratinized stratified squamous epithelium contains 4 majors types of cells and 5 layers renewed every 30-40 days basal layer always undergoing mitosis are characteristic of what skin layer?

epidermis

skin has two layers called?

epidermis (above) dermis (below)

dermis is full of CT which contains what 5 cells?

fibroblast adipocyte macrophages mast cells fibers (it also contains blood vessels, hair follicles, glands and nerves)

the ____________ layer is below the dermis but is not actually considered to be part of the skin?

hypodermis

dandruff is an excess of _____ shed from scalp

keratin

keratinocytes compose 90% of cells in the epidermis and produce ________, they act to __________ skin and underlying tissues from heat, microbes, chemicals and surface cells often _________ and only contain ________

keratin protect die keratin

accumulation of more protective keratin occurs as cells move from deepest layer to surface layer is a process called?

keratinization

nails are hard, __________, epidermal cells, the hair structure consists of _____ _______ that extends over the digits, the visible portion is called the ______ ______ and the part that is embedded in the skin fold is called the ______ _______

keratinized free edge nail body nail root

the hair shaft consists of 3 concentric rings of dead ______ cells, the ______ is the core, the cotex is several layers of flattened cells, and the ________ is a _____ layer of cells that overlap each other

keratinized medulla cortex cuticle single

the 4 epidermal cell types are?

keratinocytes melanocytes langerhan cells (dendritic cells) merkel cells (tactile cells)

lamellated granules reales what kind of secretion?

lipid rich (H2O repellent)

reticular region is in the _____ 4/5 of the dermis, and is comprised of _____ ______ CT running in all directions, it has _____ fibres to give ____, resiliency and to bind H2O, _____ fibres provide ____-______ property, and what occurs if skin is stretched too much?

lower dense irregular collage strength (extensibility = ability to stretch) elastic stretch-recoil stretch marks

what 2 layers of the epidermis contain dead cells?

lucidium corneum

in the growth stage, cells of the _____ divide, and push cells ____ from _______, in the regression stage, cells of _______ stop dividing, and hair growth ______, in the resting stage ______ happens, old hair _____ falls out of ______ and new hair grows in

matrix up bottom matrix stop nothing roots follicle

vitiligo is a partial or complete loss of _______ from patches of skin

melanin

albinism is an inherited inability to produce?

melanin (skin is pale, hair is white)

hair pigment is made by ________ at the base of the hair ______ and transferred to the cortex and medulla cells, hair colour is a genetic trait

melanocytes follicle

melanin is produced by ______, UV light exposure ______ melanin production to _____ Cells, it also helps to _____ UV light by forming a tan/sheild, we lose the an when skin _______ _____, moles are _____ localized over growth of melanocytes

melanocytes (we all have the same number but the amount they produce is different = range of skin colours) increases protect absorb flakes off benign

the stratum basal contains what cells?

melanocytes and merkle cells (basale)

there are two types of skin glands, what are they?

merrocrine (eccrine) apocrine

dermis consists of what 2 regions?

papillary reticular

the function of nails is to _____ the distal finger, help in ________, the deep layer of the ____ forms the nail ____ under the nail, the proximal portion of the nail bed (matrix) is responsible for allowing nails to ____, the _________ is thick and we therefore cannot see blood vessels in dermis underneath

protect grasping epidermis bed grow lunule

langerhan cells arise from ______ ______ ______ and migrate to the epidermis, they are involved in ______ responses and act as ____ to alert presence of foreign material

red bone marrow immune scouts

merle cells contact ________ neurons and function in _______ sensation, they are located deep in the epidermis

sensory touch

hair is present on most skin surfaces, the hair ____ protrudes from the skin, the hair _____ is embedded in skin, hair provides ____ in areas because of nerve endings associated with them (e.g. we feel a bug crawling on our arm)

shaft root sensation

melanin is a dark pigment in the form of granules that help to ______ skin against?

shield uv light (which is damaging to skin)

Merrocrine glands are _____ coiled tubular glands, that empty to _____ in palms, soles and _______, they ________ from ________

simple pores forehead function birth

the integumentary system confers the entire surface of the body and includes (5)

skin nails hair glands sensory receptors

melanin carotene hemoglobin determine what?

skin colour

arrestor pili muscle is made out of ________ muscle and attaches to hair _____, it contracts and ______ hair causing _____ ______, it has sensory nerve endings around the hair bulb

smooth follicle raises goose bumps

melanocytes compose 8% of the cells in the epidermis and are ________ shaped cells that extend into ________, they _______ and ______ pigment melanin to ________

spider keratinocytes secrete transfer keratinocytes

what are the 5 layers of the epidermis? (from deep to superficial)

stratum basale (germinativum) stratum spinosum stratum granulosum stratum lucidium stratum corneum

the follicle is a ______-like in-pocketing of the _______, which extends into the ______

tube epidermis dermis

the papillary region is in the ______ 1/5 of the dermis, and is comprised of ______ CT attaching skin to underlying tissue, _____ ______ at the junction w/ epidermis is a way to increase surface area, ______ ______ push up on the ____ and create _________ which function allows us to?

upper areolar dermal papillae epidermal ridges up finger prints (allow us to grasp better)

_____ makes up 99% of sweat composition, sweat has a pH of?

water 4-6

carotene is a ______-______ pigment, found in stratum _____, adipose tissue and the ______ layer, it is a precursor for vitamin _, and helps with vision

yellow-orange corneum subcutaneous A