Chapter 5 Book
foreign head small sensory neuron
***Functions of hair*** -hair provides protection by preventing the entrance of ___ objects (eyes, nose) -hair on the __ protects the body from UV radiation and mechanical trauma -Hair as associated with a ____ that plays a role in sensing the environment by participating in sensation
protection sensation thermoregulation
***Functions of the skin*** 1) mechanical (physical) trauma--> stretching, pressure, or abrasion; disease-causing microbes known as pathogens; and environmental hazards such as chemicals and radiation 2) sensory receptors enable the nervous system to perceive such changes, a process called ___ 3) the maintenance of a stable internal body temp through negative feedback loops
lanugo terminal hair vellus hair
***Hair color and texture vary with different types of hair*** -covers nearly the entire body. Typically falls out about the time of birth and is replace with one of the following -thicker, coarser, and pigmented. We find this on the scalp and around the eyes -thinner and non pigmented and is found over the remainder of the body
basale (germinativum) D
***Keratinocytes are organized from deep to superficial into 5 structurally distance strata (layers) Identify the layers of the epidermis*** Stratum ___ is a single layer of stem cells resting on the basement membrane. Being the closest cell to the blood supply in dermis makes these the most metabolically and mitotically active cells in the epidermis. These cells are involved in vitamin ___ synthesis and replacement of dead keratinocytes lost from more superficial layers
lacidum thick
***Keratinocytes are organized from deep to superficial into 5 structurally distance strata (layers) Identify the layers of the epidermis*** stratum ___ is a narrow layer of clear dead keratinocytes found only in ___ skin
granulosum keratin bundles lipid-based substances
***Keratinocytes are organized from deep to superficial into 5 structurally distance strata (layers) Identify the layers of the epidermis*** stratum ___ makes up the middle three to five layers of cells filled. Cells have prominent cytoplasmic granules filled with one of the following: ______ or a _______ which are both secreted by exocytosis. The hydrophobic nature of lipids provide a waterproofing that is critical for maintaining internal fluid and electrolyte homeostasis
corneum desmosomes
***Keratinocytes are organized from deep to superficial into 5 structurally distance strata (layers) Identify the layers of the epidermis*** stratum ___, the outermost layer of the epidermis, consist of several layers of dead flattened keratinocytes with thickened plasma membranes filled mostly with keratin bundles and little else. These cells are sloughed off or exfoliated mechanically as the ___ holding neighboring cells together are lost
spinosum
***Keratinocytes are organized from deep to superficial into 5 structurally distance strata (layers) Identify the layers of the epidermis*** stratum ____, the thickest layer, sits on top of the stratum basal so it still close to the blood supply. The cells in this layers are also metabolically and mitotically active
reticular
***Layers of dermis*** the ___ layer, the deep thicker layer that separates the dermis from hypodermic, is mostly dense irregular connective tissue that consists largely or irregular arranged collagen bundles as well as elastic fibers, proteoglycans, and lamellated (Pacinian) corpuscles
apocrine sweat glands sex
***The body has 4 types of sweat glands*** found in specific regions of the body such as the axillae, anal area, and areola, are large glands that release a protein-rich secretion into a hair follicle. Secretions can become odiferous once skin bacteria metabolize their contents. These glands are influenced by __ hormones and become active after puberty
eccrine sweat glands thermoregulation
***The body has 4 types of sweat glands*** the most prevalent type, are simple coiled tubular glands found in the dermis. Sweat, containing mostly water, waster products, and electrolytes, exist in ducts through a sweat pore onto the epidermal surface. The primary function of sweat from this gland is ___
malignant melanoma
***The following 3 cancers affect the skin and are linked to UV radiation exposure.*** is a cancer of the melanocytes and can be distinguished from other skin cancers and normal moles using the ABCDE rule
basal cell carcinoma keratinoyctes basale
***The following 3 cancers affect the skin and are linked to UV radiation exposure.*** the most common of all cancer types including skin cancer, arises from ____ in the stratum ___ of the epidermis. Skin that is regularly exposed to UV radiation is at risk for developing these tumors that appear was a nodule with a central crater. These tumors rarely metastasize to other tissues so they can be resolved successfully with surgical removal
squamous cell carcinoma keratinocytes spinosum
***The following 3 cancers affect the skin and are linked to UV radiation exposure.*** the second most common skin cancer, is a caner of the ____ of the stratum ___. Scaly plaques that may ulcerate and bleed are usually found on the head and neck. These tumors are more likely to metastasize than basal cell carcinoma but surgical removal is still useful
stimulus receptor effector/response homestasis
***explain the events that occur when the body temp drop below the normal range due to cold environmental conditions*** 1) body temp decreases below normal range 2) thermoreceptors detect decrease in skin and body temp 3) thfemoregulatory center in brain receives info from receptors 4) blood vessels in dermis constrict to conserve heat 5) as body temp returns to normal, feedback stops effector responses ***main difference: comes with the response that the hypothalamus triggers: it causes the blood vessels in the dermis to narrow, or constrict, a change called vasoconstriction. This decreases blood flow through the skin and redirects it to deeper tissues, which helps conserve heat***
stimulus receptor control center effector/response homeostasis and negative feedback
***explain the events that occur when the body temp rises above the normal range, due to weather extremes or abnormal conditions that cause a fever*** 1) body temp increases above normal range 2) thermoreceptors detect increase in temperature 3) thermoreceptory center in brain receives info from receptors 4) the control center stimulates effectors to respond with cooling mechanisms 5) body temp return to normal range and negative feedback stops cooling mechanisms *thermoreceptors detect when the temperature returns to normal and the responses decreases by negative feedback*
papillary repetitive
***layers of dermis*** the ___ layer, the thinner most superficial of the two layers, is composed of loose connective tissue there are special college fibers located at the dermis-epidermal junction that extends into the epidermal basement membrane for ___ trauma, such as rubbing a pair of illl-fitted shoes, which can disrupt collegen fibers and separate the epidermis from the dermis causing blisters
melanocytes basale
***other cells in the epidermis*** ____,located in the stratum ___ produce melanin which is a protein skin pigment ranging from orange-red to brown-black
merkel cells
***other cells in the epidermis*** found scattered throughout the stratum basale, detect light touch and discriminate shapes and textures. They are found in regions that are specialized for touch, such as the fingertips, lips and the base of hairs
dendrite (langerhans) cells
***other cells in the epidermis*** located in the stratum spinosum, are phagocytes that protect the skin and deeper tissues from pathogens
tactile (Meissner) corpuscles
***part of the papillae layer of the dermis*** are also found in the dermal papillae, are sensory receptors that respond to light tough stimuli and are more numerous in regions of body where sensation is a primary function such as the skin of the fingertips, lips, face, and external genitalia
dermal loops
***part of the papillary layer of the dermis*** the __ papillae are tiny projections found at the surface of the papillary layer where it comes into contact with the epidermis these contain tiny blood vessels called capillaries arranged in loops that extend up into the most superficial part of the dermal papillae. The ___ extend up into the superficial part of the dermis and up into the cells of the avascular epidermis
tumor cancerous organs
-unchecked cell division eventually leads to the formation of a large population of undifferentiated cells known as a ____ -___ tumors are able to metastasize where tumor cells spread, through the blood or lymphatic vessels to other tissues and continue to divide -damage caused by metastatic tumor cells alters the function of the invaded ___
carotene hemoglobin
2 minor pigments that have an effect on skin pigmentation
medulla cortex cuticle
A strand of hair has the following 3 regions 1) the inner ____, a soft core only found in thick hair like those found on the head, is composed of a soft keratin 2) The middle ___ is highly structured and organized with several layers of keratinocytes containing hard keratin, which provides strength to the strand 3) the outermost ___ consist of a single layer of overlapping keratinocytes containing hard keratin, which provides mechanical strength
asymmetrical border color diameter evolving
ABCDE rule: A- ____ shape (the two sides don't match) B- ____ irregularity C- ___, usually blue-black or a variety of colors D- ___, generally larger than 6mm (size of a pencil eraser) E- ____, or changing shape or size
pressure reticular
Laminated (pacinian) corpuscles repsond to sensations mainily to changes in ___ and vibration applied to the skin blood vessels, sweat glands, hair, sebaceous glands, and adipose tissue are founded embedded in the __ layer
cancer
Other factors that increase the risk for the development of ___ include: cancer-causing chemicals, toxins, or agents called carcinogens and forms of radiation
arrector pili muscle
causes a hair to stand erect when contracted. When a hair stands up, it's known as piloerection
hair
__ is too sparse to play a significant ole in thermoregulation as it does in other mammals.
hair pili
__ or __ are small filamentous structures that protrude from the surface of the skin over the entire body except in the region with thick shin, the lips, and parts of the external genitalia
skin color freckle mole
___ depends on the number of melanocytes found in a particular body region leading to uneven distribution of melanin. Fewer melanocytes are found on the palms of the hand and the soles of the feet. For example, the following of common variations in pigmentation 1) a ___ is a small area of increased pigmentation resulting from a local increase in melanin production concentrated in one spot 2) a ____ or nevus is another area of increased pigmentation that is due to a local proliferation of melanocytes instead of an increase in melanin production
keratinocytes keratin desmosomes
___ make up about 95% of the epidermis. The two structural features that keratinocytes have that make the epidermis stronger and less susceptible to mechanical trauma are: 1) are cells that manufacture ___ 2) are linked by numerous __, intercellular junctions that make the epidermis stronger
terminal hair hair color melanocytes melanocytes
___ replaces much of the vellus hair after puberty, which varies by gender with more hair replacement occuring in males than females ___ is largely determined by the melanin produced in the matrix by melanocytes. ___ produce a range of colors from blond hair, which has little melanin, to black hair, which has lots of melanin, while red hair has a special reddish pigment containing iron. ____ produce less melanin with aging so hair eventually turns gray or white
thick thin thin
___ skin contains all 5 epidermal strata and a very thick stratum corneum ___ skin has more abundant hairs, sebaceous glands, and sweat glands ___ skin lacks the stratum lucidum and so has only 4 epidermal strata. and its stratum corneum and other strata are much thinner than those in thick skin
keratinocyte life cycle corneum 40-50
___: the location and functions of the epidermis subjects it to both physical and environmental stress. The stratum ___ is continuously shedding dead cells that must be replaced from the deeper layers to maintain the integrity of the epidermis. The migration from the deepest strata to the stratum takes a cell between ___ days to complete
proteoglycans
____ are present in the reticular layer to draw water into the ground substances, which hydrates the skin and makes it appear firm
elastic fibers
____ in the reticular layer enables the dermis to return to its original shape and size after being stretched
wound
a common skin pathology, is defined as any disruption in the skins integrity and include the following specific injuries: lacerations or cuts, burns, and skin cancers
cyanosis blusih
a sign that someone needs immediate attention, occurs when hemoglobin has less bound oxygen; less oxidized iron reduces the reddish color of blood to a faint ___ hue. This happens when an individual has breathing problems, when hemoglobin and red blood cell levels are too low, or when hemoglobin is unable to bind to oxygen sing that a persons in trouble
burn
a wound caused by agents such as heat, extreme cold, electricity, chemicals and radiation
carotene corneum corneum
a yellow-orange pigment found in food items such as egg yolks and orange vegetables This lipid soluble pigment accumulates in the stratum ___ This imparts a slight yellow-orange color that is particularly visible in the stratum __ of thick skin
ceruminous glands cerumen
are modified apocrine glands that release a thick secretion called ____ (ear wax) into hair follicles found in the ears.
epidermis hypodermis hypodermis
about 50% of the cells in the ___ are too far from adequate blood supply to sustain life; the superficial layers are made up entirely of dead cells The ___ also known as the superficial fascia or subcutaneous fat, is deep to the dermis. Although not part of the skin, it does anchor hi skin deeper structures like muscle and bone. The ___ is made of loose connective and adipose tissues and has an abundant blood supply
sweat sebaceous hair nails
accessory structures of the skin are embedded in the cutaneous membrane and include ___ glands, ___ glands, __ and ___
skin markings epidermal ridges reticular
are visible lines in the epidermis created by the interaction between the dermis and epidermis. These are best seen in the thick skin of the palmar surfaces of the hands and fingers and the plantar surface of the feet/toes Dermal ridges are found in these areas where the dermal papillae are more prominent due to the presence of the thick collagen bundles. Dermal ridges indent the overlying epidermis to create ___. which enhances the gripping ability of the hands and feet the ___ layer is also respobsible for skin markings associated with tension or lines, cleavage lines and flexure lines
hair growth
averages between 1-1.5cm per month but varies between individuals. Growth is not continuous but occurs in a cycle with the following two main phases: growth stage and resting stage
reticular
collagen fibers in the ___ layer of the dermis strengthen the dermis and help prevent traumatic injuries from reaching deeper tissues
sebum
contains cell fragments and debris in addition to lipids
UV radiation
damages the DNA of the melanocytes, which causes the melanin to rapidly darken
melanoma
early detection of __ is critical due to its tendency to metastasize to other tissues. These are treated with surgical removal and possibly other options such as radiation therapy and chemotherapy
hemoglobin
found in red blood cells, is an iron-containing protein that binds to and transports oxygen throughout the body
shaft root
hair is composed of two main parts, the __ and the __. Both are made up of stratified squamous keratinized epithelial cells in various stages of development, first the shaft followed by the root
nails
hard accessory structures that are located at the ends of the digits, are composed of stratified squamous epithelium filled with hard keratin
integumentary system
has the following function that are critical for protecting the underlying organs or for maintaining homeostasis
immediate response to UV radiation
immediate action is to oxidize the melanin already formed within the keratinocytes, which causes the melanin to rapidly darken
roots papilla bulb matrix
is a segment of hair that is embedded in the dermis where it is surrounded by a small sensory neuron. The root is indented at its base by a projection of blood vessels from the dermis called a hair ____. The root and their papilla are collectively known as the hair ___. Many epithelial cells in the root are still alive, having not completed the keratization process. A small number of keratinocytes called the ___, found at the base of the root, actively divide mitosis
avascular
lacks a blood supply
cerumem
lines the canal leading into the ear, where it lubricates the tympanic membrane and traps incoming particles before they reach the membrane
melanosomes
melanin is composed of two molecules of the amino acid tyrosine that are chemically bonded by a series of reactions catalyzed by the enzyme tyrosinase. These reactions occur in a stepwise fashion within a special vesicle called a _____
UV radiation (sun or sunlamps)
melanin synthesis increases with exposure to natural or artificial ___, which leads to tanning or darkening of the skin pigmentation. This has both immediate and delayed effects of skin pigmentation
growth stage
mitosis occurs within the cells of the matrix in the root. As the cells divide, those above them are pushed away from the blood supply, keratinized, and die, in a similar manner to what takes place in the epidermis. This stage last anywhere from about a month in the eyelashes to 6 years in the scalp
sebaceous glands
most numerous in the face and scalp. Also found throughout the body with the exception of the palms and soles
matrix
nail growth occurs at the nail ____ where actively dividing cells push neighboring keratinocytes distally, which die once they have completed keratinization and have been cut off from the blood supply. Fingernails grow an average of 0.5mm per week while toenails grow more slowly
lunula
nails dont contain melanocytes so are mostly translucent expect at a region called the ___. The ___ is a half-moon shaped region of the proximal nail plate that represents an accumulation of keratin
pallor
occurs when the blood flow in the dermis decreases, resulting in loss of the normal pinkish hue most visible in fair-skinned individuals. The epidermis may take on whitish color of collagen in dermis. This happens when the body is trying to conserve heat; in extreme cases, so little blood is flowing through the skin that collagen in the dermis is visible the color also depends on how much oxygen is bound to it. When high oxygen, brighter red because its iron becomes more visible
erythema
occurs when the blood flow in the dermis increases, causing a color change that makes the skin more red This happens when body is injured by trauma (breaking bone) infection (as blood flow increases to the injured area) and when the body is trying to release heat while exercising
cancer
one of the most common diseases in the world, is caused by mutations in the DNA that induce a cell to lose control of the cell cycle
third-degree burns
or full thickness burns are the most damaging wounds, which involve the epidermis, dermis, and hypodermic and potentially even deeper tissue like muscles and bones
second-degree burns
or partial thickness burns, involve the epidermis and part of the dermis, which can result in pain, blistering, and scarring
first-degree burns
or superficial burns, are minor wounds that only damage the epidermis. Skin may develop erythema or a red appearance and some mild pain without any permanent damage
hemoglobin hemoglobins dermis
oxygen binds to the iron found in ___ in an oxidation reaction, which is the same reaction that causes iron to rust. Oxidized iron changes color to a bright orange-red, which gives blood its color __ affect on skin color is an indirect result of blood flow in the dermis. Light-skinned individuals have little pigment in their epidermis, rendering it somewhat translucent the color of blood in the deeper __ is visible through the epidermis
melanin melanocytes
responsible for much of the pigmentation of the skin, hair, and irises of the irisies ___ have several arms or extensions of plasma membrane that are in contact with neighboring keratinocytes in the stratum basal and spinosum
sebum
sebaceous glands empty into a hair follicle or a small pore that makes and secretes ___
melanin
skin color, mostly determined by various amounts of the orange-red to black protein pigment ___, is produced by melanocytes in the stratum basal of the epidermis
dermis
skin contains sensory receptors and arrector pili muscles, which are small bands of smooth muscle associated with ___
epidermis dermis
skin is also known as the cutaneous membrane and has 2 main components: 1)____-consist of keratinized stratified squamous epithelium that rests on top of a basesment membrane 2)___-consist of loose connective tissue and dense irregular connective tissue
D
skin plays a critical role in vitamin ___ synthesis. This is a hormone that relies on cells found deep in the epidermis for converting vitamin D from an inactive form or precursor, known as cholecalciferol, to its active form, called calcitriol.
excretion
small amounts of waste products are eliminated from the body through the skin
continous barrier skin skin
stratified squamous, keratinized epithelium provides a ____ against invasion. Glands also create a slightly acidic pH, which inhibits pathogen growth. The __ protects again UV light; the __ also repels ionic and polar covalent molecules, which is critical to maintain fluid and electrolyte homeostasis
sheath arrector pili
surrounding the epithelial root is a dermal root ___ that consist of connective tissue that supports the follicle and separates it from the dermis Small bands of smooth muscle called ___ muscles attract to the dermal root death on one end and the dermal papillary layer on the other
dermis
the __ is a highly vascular layer deep in the epidermis that serves the following functions: houses the blood supply of the epidermis, contains sensory receptors, and anchors the epidermis in place the ___ is composed of two distinct layers made up of two types of connective tissues: papillary layers, reticular layer
palms soles
the ___ of the hands and the __ of the foot are subjected to a great deal of mechanical stress so these regions of skin have adapted to the added stress
hair nails glands
the accessory structures or appendages of the integument include __, ___, and ___ that are derived from only epithelium that assist in the overall function of the integumentary system
resting stage
the cells in the matrix cease dividing and start to die. The follicle shortens somewhat and hairs pushed up near the surface of the follicle, which remains formant for one to several months. At this point, the hair may fall out on its own, or a new hair may push it out when the growth stage resumes
avascular
the epidermis is ____ and must rely on the diffusion of oxygen and nutrients from blood vessels in the deeper dermis, which limits its thickness
keratinocytes
the epidermis is the most superficial layer of skin and is composed of several cell types, the most numerous of which are the ___
skin
the largest organ in the body. Is more than just an outer covering; it is a complex organ with many vital functions important for hemostasis
plate bed matrix plate
the nail __, the most visible component of the nail, sits on top of an underlying nail __. The nail plate is divided into the nail body and nail root, which lies under the nail ___ actively divides and produces new cells. these flooded region of skin surround and reinforce the nail __: the proximal nail fold, medial nail fold, and lateral nail fold
shaft
the portion projecting from the skins surface composed of columns of keratinized epithelial cells and they are all dead
nail
the primary function of a nail is to protect the underlying tissue, the distal tips of the fingers and toes, from trauma. Nails can be used as tools, enabling more precise gripping of items when they are picked up
follicle sheath
the root is embedded in the hair ___, which is an infolding of the epidermis called the epithelial root health that extends deep into the dermis or even hypodermic The epithelial root ___ has an outer component that is anchored tightly to the hair root.
sweat (sudoriferous) gland sebaceous gland
the skin contains two basic types of glands both derived from epithelial cells in the epidermis but located deeper in the dermis: _____ that produce swear and _____ that produce oily sebum
delayed effect of UV radiation
these become visible about 72 hours after exposure to UV but last longer than melanin oxidation The amount of UV radiation melanin can absorb is limited as is the protection it provides
secondary function of melanin
to decrease the synthesis of vitamin D in reponse to UV radiation
D
vitamin __ is required for calcium ion absorption from the small intestines.
sebum
waxy, oily mixture consisting largely of various lips. Use holocrine secretion, during which the secretory cell accumulates its products until rupture occurs
rule of nines
we can divide the body into 11 areas, each representing 9% of the total body surface area. So if the burn involves the entire right lower limb covering 18% of the body, and a burn involving the entire right upper limb and anterior trunk covers 27% of the body such estimates are important because they predict they complications that can arise from a burn
calcium ions
what is important for nerve function, muscle contraction, building and maintaining bone tissue and other physiological processes