Human Anatomy Module 2: CH. 5
The continual life cycle of keratinocytes being sloughed and replaced by cells undergoing mitosis takes about _________.
40-50 days
What does cyanosis signify?
A person has oxygen-starved skin.
What is the medical term used for baldness?
Alopecia
What stands hairs on end, causing piloerection?
Arrector pili muscle
What is the most common type of skin cancer that results in the formation of a nodule with a central "crater" that ulcerates?
Basal cell carcinoma
Which of the following characteristics is not part of the ABCDE rule?
Border regularity
Which of the following molecules is responsible for yellow-orange skin pigment?
Carotene
What modified apocrine glands secrete ear wax?
Ceruminous glands
What cells of the epidermis function as phagocytes of the immune system?
Dendritic cells
What tissue composes the reticular layer of the dermis?
Dense irregular connective tissue
Where are blood vessels housed that nourish the epidermis?
Dermal papillae
What are the main components of the cutaneous membrane?
Epidermis and dermis
Which of the following sensations is not detected by the skin?
Equilibrium
Which of the following characteristics is typical of a first-degree burn?
Erythema
Which of the following cells is associated with the dermis?
Fibroblast
Which of the following cells are associated with the dermis?
Fibroblasts
Which of the following structures is not found in thick skin?
Hair follicles
In which of the following locations are dead keratinized cells found?
Hair shaft
What type of secretion do sebaceous glands use?
Holocrine secretion
What is the main tissue of the epidermis?
Keratinized stratified squamous epithelium
What is the most numerous cell type in the epidermis?
Keratinocyte
What type of hair does a fetus have?
Lanugo
The __________ is the opaque crescent-shaped area near the proximal nail fold.
Lunula
What is the primary pigment found in skin?
Melanin
Which of the following components do vellus hairs lack?
Pigment
What is the oily waxy substance secreted by sebaceous glands called?
Sebum
What stimulates the secretion of sebum?
Sex hormones
Where are melanocytes located?
Stratum basale of the epidermis
From superficial to deep, what is the correct order of the layers of the epidermis in thick skin?
Stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, and stratum basale
Which layer of the epidermis is not present in thin skin?
Stratum lucidum
What is the thickest layer of the epidermis?
Stratum spinosum
What are the sensory receptors in the dermal papillae that respond to light touch stimuli called?
Tactile (Meissner) corpuscles
What is the thicker, coarser, more pigmented hair found on the scalp?
Terminal hair
Why do keratinocytes in the superficial strata of the epidermis die?
They are too far away from the blood supply in the dermis.
What is the primary function of melanin?
To protect the DNA of keratinocytes from mutations induced by ultraviolet (UV) radiation
What enzyme plays a major role in skin color?
Tyrosinase
Which of the following functions is not associated with the skin?
Vitamin A synthesis
What is the primary function of vitamin D?
Vitamin D is required for calcium absorption from the small intestine.
Glands that secrete products into hair follicles are called __________.
apocrine glands
Humans often purchase antiperspirants and deodorants to suppress and mask the odors of secretions from the __________.
apocrine glands
Keratinocytes in the stratum corneum __________.
are dead and filled with keratin
The majority of cells in the epidermis arise from mitotic activity in stratum __________.
basale
The rule of nines is used to estimate the percentage of body surface area affected by __________.
burns
We have unique patterns on our fingers, toes, palms, and soles created by __________.
epidermal ridges
The most superficial component of the skin is the __________.
epidermis
Tommy fell and skinned his knee. The scrape did not bleed. He must have only damaged the __________.
epidermis
The cuticle around a nail is the __________.
eponychium
Squamous cell carcinoma arises from __________.
keratinocytes in stratum spinosum
The ABCDE rule is used to distinguish normal moles from ____________________.
melanomas
The nail body covers the __________.
nail bed
The __________ is the part of the nail root that contains actively dividing cells.
nail matrix
The most superficial layer of the dermis is the __________.
papillary layer
Extreme stretching of the reticular layer of the dermis results in_______________.
permanent stretch marks
The ____________ is the largest organ in the body.
skin
The _______________ is a location of thick skin.
sole of the foot
The most superficial layer of the epidermis is called the __________.
stratum corneum
Eccrine glands produce __________.
sweat containing mostly water
Mammary glands are specialized __________.
sweat glands
Skin without keratin would be more likely to __________.
tear upon being mechanically stressed
Melanin is produced upon exposure to __________.
ultraviolet (UV) radiation