Chapter 5 Sections 1-2
Why are lines of cleavage clinically significant?
a cut parallel to a cleavage line will remain closed
Sagging and wrinkling of the integument are due to __________.
a decrease in the elastic fiber network of the dermis
When ruptured dermal blood vessels leak into the dermis, a __________ may form.
bruise
Which of the following is an orange-yellow pigment that is found in certain food items, such as carrots and squash?
carotene
What are the two basic factors that interact to produce skin color?
circulatory supply and pigment concentration
The reticular layer of the dermis is composed of what kind of tissue?
dense irregular connective tissue
What are the two layers of the cutaneous membrane (skin)?
dermis and epidermis
Which of the following is not an accessory structure in the integumentary system?
epidermis
Which structure is an accessory structure rather than part of the cutaneous membrane?
exocrine glands
Where is epidermal growth factor produced?
glands of the duodenum
Accessory structures of the skin include the __________.
hair follicles and sebaceous and sweat glands
What is the water-resistant, fibrous protein that fills the cells of the outer layers of the epidermis and helps slow dehydration?
keratin
Which type of cell is the most abundant epithelial cell in the body and dominates the cellular composition of the epidermis?
keratinocyte
Which of the following does the integument not synthesize or produce?
lipids
Which of the following is a dark brown, yellow-brown, or black pigment produced by pigment cells in the stratum basale?
melanin
What are the two layers of the dermis?
papillary and reticular layers
The integumentary system has a protective function. From which of the following does the skin not protect us?
pressure and pain stimuli
Which of the following is not an effect of epidermal growth factor (EGF) on the epidermis?
simulating the synthesis of melanin
In which layers of the epidermis do mitotic divisions occur?
stratum basale and stratum spinosum
What is the correct order of strata from the basement membrane to the free surface of the epidermis?
stratum basale, stratum spinosum, stratum granulosum, stratum lucidum, stratum corneum
In thick skin, what is the thickest (most cell layers) stratum of the epidermis?
stratum corneum
What is the most superficial layer of the epidermis?
stratum corneum
Which epidermal stratum is the most superficial and is composed of 15-30 layers of dead, keratinized cells that eventually are shed from its surface?
stratum corneum
Which epidermal layer is found only in thick skin?
stratum lucidum
Which of the following functions is NOT associated with the skin?
synthesis B vitamins
Differences in skin color among individuals are the result of __________.
the different levels of melanin synthesis