HLSC 2416 Exam 3 Questions and Answers
largest; 20 - Answer- The skin is the __________ organ system in the body -- it covers _____ square feet of surface area in the average adult.
epidermis (outer) and dermis (inner0 - Answer- What are the two layers of the skin?
a subcutaneous layer of adipose tissue - Answer- What lies beneath the two layers of skin?
a thin but tough protective outer layer - Answer- Explain the epidermis.
they are bound tightly together in sheets that form a rugged protective barrier - Answer- How are cells organized in the epidermis?
the inner layer of the epidermis that forms new skin cells - Answer- Explain the basal cell layer.
keratin - Answer- What is the major ingredient in skin cells formed in the basal cell layer?
melanocytes; melanin - Answer- The ______________ interspersed along the basal cell
layer produce the pigment __________, which gives brown tones to the skin and hair.
True: only the amount of melanin they produce varies with genetic, hormonal, and environmental influences. - Answer- T/F: People of all skin colors have the same number of melanocytes.
the layer above the basal layer where new cells migrate to and flatten; consists of dead keratinized cells that are interwoven and closely packed (cells are constantly being shed, or desquamated, and are replaced with new cells) - Answer- Explain the horny cell layer.
every 4 weeks - Answer- How often is the epidermis completely replaced?
palms and soles - Answer- Where is the skin thicker because of work and weight bearing? 1. melanin (brown)
2. carotene (yellow-orange)
3. red-purple tones in underlying vascular bed - Answer- Where is skin color derived from?
the inner supportive layer consisting mostly of connective tissue/ collagen - Answer- Explain the dermis.
a tough, fibrous protein that enables the skin to resist tearing - Answer- What is collagen?
dermis - Answer- The nerves, sensory receptors, blood vessels, and lymphatics lie in the _________.
hair follicles, sebaceous glands, and sweat glands - Answer- What are some appendages from the epidermis that are embedded in the dermis?
adipose tissue (lobules of fat cells) that stores fat for energy, provides insulation for temperature control, and aids in protection
also gives skin increased mobility - Answer- Explain the subcutaneous layer's structure and functions.
keratin - Answer- Hairs are threads of __________.
shaft; root - Answer- The hair ________ is the visible projecting part, and the _______ is below the surface embedded in the follicle.
the expanded area at the root where new cells are produced at a high rate - Answer- What is the bulb matrix?
independently (some are resting and some are growing) - Answer- Each follicle functions ________________.
muscles that contract and elevate the hair so it resembles "goose flesh" when the skin is exposed to cold or in emotional states - Answer- What are arrector pili muscles?
vellus and terminal hair - Answer- What are the two types of hair?
Fine, faint hair that covers most of the body - Answer- What are vellus hairs?
darker, thicker hair that grows on the scalp and eyebrows and, after puberty, on the axillae, the pubic area, and the face and chest in the male - Answer- What are terminal hairs?
glands that produce a protective lipid substance, sebum, which is secreted through the hair follicles - Answer- What are sebaceous glands? sebum - Answer- ________ oils and lubricates the skin and hair and forms an emulsion with water that retards water loss from the skin
everywhere except the palms and soles; most abundant on the scalp, forehead, face, and chin - Answer- Where are sebaceous glands located?
eccrine and apocrine - Answer- What are the two types of sweat glands?
-coiled tubules that open directly onto the skin surface and produce a dilute saline solution called sweat
-widely distributed
-mature in 2-month old infant - Answer- What are eccrine glands?
-glands that produce a thick, milky secretion and open into the hair follicles
-mainly in axillae, anogenital area, nipples, and navel
-become active during puberty - Answer- What are apocrine glands?
bacterial flora residing on the skin surface reacts with apocrine sweat - Answer- What produces the characteristic musky body odor?
hard plates of keratin on the dorsal edges of the fingers and toes - Answer- Describe nails.
lunula - Answer- The _________ is the white, opaque, semilunar area at the proximal end of the nail.
covers and protects the nail matrix - Answer- What is the function of the cuticle?
protection
prevents penetration
perception
temperature regulation
identification
communication
wound repair
absorption and excretion
production of vitamin d - Answer- Name some functions of the skim.
at 3 months gestation - Answer- When do hair follicles develop in the fetus?
the fine downy hair of the newborn infant (replaced by vellus hair in the first few months after birth) - Answer- What is lanugo?
a thick, cheesy substance made up of sebum and shed epithelial cells (present at birth) - Answer- What is vernix caseosa? -thin, smooth, elastic, more permeable (greater risk of fluid loss)
-decreased size and production of sebaceous glands until puberty
-temp regulation not as effective (eccrine glands do not secrete to heat until first few months; cannot contract and shiver)
-pigment system inefficient at birth - Answer- What are some ways newborn's skin differs from adults?
-epidermis thickens, toughens, and darkens
-becomes better lubricated
-accelerated hair growth
-apocrine gland secretion increases at puberty
-sebaceous glands become more active (oily skin and acne)
-subcutaneous fat deposits (especially in females) - Answer- How does the skin change as the child grows?
-females: areola enlarges and darkens, breast tissue develops
-males: course facial hair
-both: pubic hair develops then axillary hair - Answer- What are some secondary sex characteristics that appear during adolescence and are evident in the skin?
-peripheral vasculature dilates
-sweat and sebaceous glands increase secretion
-fat deposits on buttocks and hips - Answer- How does the skin change in pregnant women?
-loses elasticity, folds and sags
-thin, dry, lax, wrinkled
-epidermis thins and flattens
-loss of elastin, collagen, and subcutaneous fat and muscle tone
-sweat and sebaceous glands decrease (dry skin) - Answer- How does skin change in aging adults?
the dermis thins and flattens - Answer- Why does wrinkling occur?
collagen - Answer- The loss of ___________ increases the risk for shearing, tearing injuries.
dark red discolored areas (caused from minor traumas in aging adults) - Answer- What is senile purpura?
aka razor bumps or ingrown hairs - Answer- What is pseudofolliculitis?
the "mask of pregnancy" a patchy tan-to-dark brown discoloration of the face - Answer- What is melasma?