Bio 227 LS 6
migration of a keratinocyte from the stratum basale to the stratum corneum takes about ____ weeks.. The dead keratinized cells usually remain in the exposed stratum corneum layer for an additional ____ weeks. Overall, keratinocytes are present for about ____ month following their formation
2, 2, 1
healing of second degree burns take approximately ___ weeks, and slight scarring may occur
2-4 weeks
keratinocytes of the epidermis are usually present for about ___ weeks
4
Match the letter with the structure or layer of the dermis
A: reticular layer B: dermal papillae C: papillary layer D: epidermis E: dermis
scientifically, thinning of the hair on the scalp is called
alopecia
the subcutaneous layer or hypodermis is made up of two types
areolar, adipose connective tissue
what are functions of the skin
barrier to water loss, heat regulation
In the development of embryonic skin, the ___ layer gives rise to the epidermis and the ___ gives rise to the dermis
basal, mesenchyme
in the second step of wound healing, a ___ forms
blood clot
a hemangioma is a congenital anomaly that results in skin discoloration due to ___ that proliferate and form a benign tumor
blood vessels
____ hemangiomas or 'strawberry-colored birthmarks' appear in the skin as bright red to deep purple nodules that usually disappear in childhood
capillary
in the first step of wound healing, blood brings ___ proteins, numerous white blood cells, and antibodies to the site
clotting
lines of cleavage in the skin relate to the predominant orientation of ___ fiber bundles
collagen
three main variations in the epidermis
colorations, skin markings, thickness
in thick skin, the layers of epidermis that contain dead keratinocytes are the stratum lucidum and stratum
corneum
people most likely to develop skin cancer are those with
fair skin
in what two ways are damaged skin tissues normally repaired
fibrosis and regeneration
friction ridges are used as forensic tools because they can leave noticeable prints on touched surfaces, commonly called
fingerprints
potential complications of a wound under repair include ____ loss and _____
fluid loss and infection
the vascular connective tissue that initially forms in a healing wound is called
granulation tissue
when skin has been damaged, which integumentary system components are not repaired
hair follicles, nerves, exocrine glands
the subcutaneous layer is also known as the ___ or superficial fascia
hypodermis
the most numerous cells of the epidermis are ____ and the protein they produce is called ____
keratinocytes, keratin
which organs are involved in making calcitrol, the active form of vitamin D
kidney, skin, liver
tactile cells are described best by which of the following
large epithelial cells also called merkel cells can be stimulated by light pressure can be stimulated by light touch
which organ are involved in making calcitriol, the active form of vitamin D
liver, kidney, skin
the color of hair is the result of
melanin production
a nevus is commonly referred to as a ____. it is a harmless, localized growth of _____ forming cells
mole, melanin
when skin has been damaged, which integumentary system components are not repaired
nerves, hair follicles, exocrine glands
during the process of keratinization, the cell's ___ and organelles of the cells disintegrate and the cells start to die
nucleus
the ___ layer of the dermis contains areolar connective tissues and dermal papillae
papillary
match the terms with their function
periderm: layer of cells covering the developing embryonic epithelium vernix caseous: waterproof protective covering composed of sebum and sloughed off cells mesenchyme: layer of embryonic cells that develop into the dermis
mammary glands only becomes functional in which of the following conditions
pregnant females lactating females
among the stimuli detected by the sensory receptors of the skin are ____
pressure, cold, vibration
match the structure of hair to their specific functions
protection: scalp hair covers the scalp and shields it from sunburn and injury Heat retention: blanket of thick hair on scalp Sensory reception: hair roo plexuses visual identification: color and density of hairs on scalp
the ___ layer of the dermis consists primarily of dense irregular connective tissue with large bundles of collagen fibers
reticular
the hair follicle is an oblique tube that surrounds the hair
root
terminal hair is the type of hair that grows on the ____
scalp
sebaceous glands are activated primarily by ___ during puberty in both sexes
sex hormones
epidermal dendritic cells are found in which of the following strata
spinosum and granulosum
epidermal dendritic cells are found in which of the following strata?
spinosum and granulosum
as a result of the aging process, hair follicles can actually ___ production of hairs
stop
skin is classified as either thick or thin based on two parameters: the number of epidermal ___ in the epidermis and the relative ___ of the epidermis rather than the thickness of the entire integement
strata, thickness
___ glands are also called sweat glands
sudoriferous
On many parts of the body, the components of the dermis include blood vessels, ___ glands, ___ glands, hair follicles, nail roots, sensory nerve endings, and smooth muscle tissues
sweat and sebaceous glands
major function of merocrine sweat gland is
thermoregulation
the major function of merocrine sweat glands is
thermoregulation
skin grafting is normally necessary for
third-degree burns
the release of water vapor from sweat glands when we are not sweating is a process called
transpiration
True or false: skin cancer can develop in people of any age
true