ch 2.1 Flashcards
T/F?
bc of the hypodermics skin is able to slide over muscles
true
when we wear leather shoes or jackets, we are wearing the hide of an animal. this corresponds the ___ in humans
dermis
the reticular later of the dermis is made of ______ connective tissue
dense irregular
sensory receptors in the dermal papillae are the primary sensors for pain, heat, and cold are called ___
nerve endings
T/F?
like the reticular later, the papillary layer also includes collagen and elastin
true
t/f?
the hypodermics is not technically a layer of the skin
true
T/F?
flexure lines can be found in the wrists, fingers, toes, and soles
true
which layer of the dermis has its collagen and elastin fibers arranged in a loosely woven mat with many blood vessels running through it?
papillary
t/f?
flexible lines in the palm can provide reliable information about a persons expected lifespan
false
stretch marks are white or red lines caused by rapid weight gain such as that during pregnancy. the marks exist in areas where the ___ has been torn
dermis
t/f?
skin cells produce enzymes that can disarm cancer causing chemicals that penetrate the epidermis and also activate the steroid hormones
true
failing body temperature will cause blood vessels near the skin to ___ in an attempt to conserve heat and warm the body
constrict
sensory receptors that respond to stimuli from outside the body are called ___.
exteroreceptors
t/f?
cutaneous sensory receptors are part of the nervous system
true
t/f?
most nitrogen containing waste products are excreted from the body through the skin
false
what is known as a “bed sore”?
decubitous
separations between collagen bundles in the reticular later of the dermis give surgeons lines to follow when making incisions. these are called ___ lines
cleavage
areas where the dermis is more tightly secured to deeper structures from folds more commonly known as ___ lines
flexure
which skin later anchors the skin to the muscles beneath it?
hypodermis
fingerprints arise from epidermal ridges which are cause by underlying projections from the ___ layer of the dermis
papillary
t/f?
epidermal ridge patterns caused by underlying dermal papillae do not change with growth and aging
true
the sensory receptors found in the papillary layer in the dermis that are sensitive to light and touch are called___ corpuscles.
meissners
t/f?
like the reticular layer, the papillary layer also includes collagen and elastin
true
t/f?
surgical incisions made along cleavage lines are more likely to leave a scar than incisions made at an angle to those lines
false
when sweat on the surface of the skin evaporates, body temperature will___
fall
skin cells produce an enzyme called ___, which aids the natural turnover of collagen in the skin, thus deterring the formation of wrinkles
collagenase
in which layer of the dermis are phagocytes able to freely wander and patrol the area for invaders that may have penetrated the skin?
reticular
what does the dermis have a rich supply of?
veins , arteries , nerves , and lymphatic vessels
the network of blood vessels deep in the reticular layer that nourishes the entire dermis is called the ___
cutaneous plexus
which layer of the dermis had collagen fibers running mostly parallel to the skins surface?
reticular
the bumps in the upper layer of the dermis that are responsible for the formation of fingerprints are called____
dermal papillae
rising body temperature will cause blood vessels near the skin surface to ___ in an attempt to release heat to the environment and cool the body
dilate
the hypodermis is made mostly of ___ tissue
fat
the dermal sublayer that is immediately superficial to the hypodermis is the ___ layer
reticular
the dermal layer of skin has __ sublayers and the epidermal layer has __ sublayers
2 & 5
“superficial fascia” is another term for the ___
hypodermis
t/f?
if blood is needed in a particular part of the body, it can be diverted from other areas such as the skin.
true
t/f?
laser tattoo removal can target pigments of several different colors simultaneously
false
long term risks are associated with the quantity and type of pigment left in the skin producing the tattoo. for example, degradation products of ___ compounds have been found to be carcinogenic (cancer-causing)
azo
t/f?
tattoos have been around for at least 5000 years?
true
into which layer of the skin are pigment particles injected during the tattooing process?
dermis
although pigment particles in tattoo ink are recognized as foreign invaders, the ink remains in the skin because the pigment particles are too ___ for ___ in the papillary layer of the dermis to destroy
large, macrophages
as keratinocytes in the epidermis are born and move upward, they undergo a controlled cell death. this process is called___
apoptosis
blisters form between the ___ (below) and ___ (above)
dermis & epidermis
in the stratum basale, new keratinocyte cells are born through the process of ___.
mitosis
a fluid filled pocket between the dermis and epidermis cause by burns or repeated friction is called a ___
blisters
the tough, fibrous protein that is the main component of epidermal cells is ___.
keratin
a callus that has become cone-shaped and protrudes to the skin, causing pain is called a ___
corn
the ___ layer consists of 3-5 layers of thin, flat, mostly dead keratinocytes
stratum granulosum
what substance accumulates on the “sunny side” of a keratinocyte, protecting the DNA in its nucleus from the suns UV rays?
melanin
when comparing types of epithelial cells, the term that means “one layer” is ___
simple
the receptors that sense light touch and are especially abundant in the stratum basale of the hands and feet are called ___
merkel cells
in the stratum basale, new keratinocyte cells are born through the process of ___
mitosis
cells that make the pigment melanin are called ___
melanocytes
epithelial cells that have a flattened shape are referred to as ___
squamous
___ cells in the stratum spinosum are responsible for engulfing any bacteria, foreign particles, or damaged cells they find in this layer
Langerhans
the ___ consists of 20-30 layers of dry, dead, keratin filled cells with glycolipids acting as the mortar between them
stratum corneum
which layer of the epidermis consists of a single to of activity dividing keratinocyte stem cells?
stratum basale
in the stratum basale, each keratinocyte ___ cell divides, producing two ___ cells. one of these migrates upward and the other remains behind to divide again
stem, daughter
the most superficial layer of the epidermis is called the ___
stratum corneum
“thick skin” does not contain which epidermal layer?
stratum lucidum
“thick skin” is skin that contains the ___, such that of the palms, soles, fingers, and toes
stratum lucidum
___ refers to the shingle like remnants of the stratum corneum sloughed off by the skin on the scalp
Dandruff
in the stratum ___, keratinocytes appear to have prickly borders due to being pulled right at the desmosomes by which they connect with adjacent cells
spinosum
the bumps under the layer of the dermis that are responsible for the formation of fingerprints are called___
dermal papillae
T/F?
modern humans evolved from africa and then migrated throughout the world
true
the birth defects anencephaly and spina bifida are linked to a deficiency of ___ in the diet. this is related to the skin because ___ helps prevent this vitamin from being degraded from UV rays
folate, melanin
the median age at which people are diagnosed with melanoma is 63. this is evidence that skin cancer may not explain the strong selective pressure for dark skin in high UV areas because people of that are past their ___ years and have already passed on their genes to their offspring
childbearing
people with lighter skin have a survival and reproductive advantage in a ___ UV environment
low
inherited traits that provide a survival and reproductive advantage in a particular environment are ___ likely to be passed on to the next generation and thus become ___ common over time
more, more
rockets is a bone disease caused by deficiency of the mineral ___. Production of ___ in the skin is necessary for the absorption of this important mineral
calcium, vitamin D
t/f?
UV intensity predicts skin color for non indigenous populations
false
bronzing of the skin is characteristic of Addison’s disease, a condition in which the adrenal cortex fails to produce which two steroid hormones?
aldosterone & cortisol
on which side of the keratinocyte does melanin accumulate?
on the side most directly hit by the suns UV rays
the yellowish red form of the melanin pigment is called ___
pheomelanin
t/f?
jaundice is a common condition for both pre term and full term newborns
true
The deepest epidermal layer in which melanocytes are found is the stratum ___ , followed by the stratum ___
basale, spinosum
melanosomes full of ___ are transported to surrounding ___ where melanin acts to protect the nucleus and the DNA it contains
melanin, kertinocytes
the brownish -black form of the melanin pigment is called ___
eumelanin
t/f?
whether you be tan or burn in the sun is determined by your skin type
true
blood loss, low blood pressure, anemia, or emotional stress can cause a whitening of the skin called ___
blanching
t/f?
melanocytes of darker skinned people produce more eumelanin and their keratinocytes retain it longer
true
excessive UV exposure causes ___ fibers in the skin to clump which leads to the appearance of wrinkles
elastin
in a person with jaundice, the ___ is unable to recycle red blood cells and break down bilirubin quickly enough
liver
in the ABCDE rule for evaluating moles, the A stands for ___
Asymmetry
there is not a significant increase in UV protection for sunscreens beyond an SPF rating of ___
30
t/f?
UV exposure can come from tanning beds
true
t/f?
a single use of tanning bed increases the risk for developing skin cancer by 20%
true
skin cancer is an abnormal growth of ___ cells
epithelial
the ABCDE rule is used to evaluate __ to determine whether or not they are cancerous
moles
most sunscreens are effective for up to ___ hours
2
t/f?
epithelial cells divide quickly and many skin cancers develop quickly
true
t/f?
all sunscreens block both UV-B and UV- A radiation
false
