Biol Test 2
The tympanic membrane is protected from the entry of dirt and small insects into the ear canal by the presence of ___and hairs
cerumen
The _______ forms the bulk of a hair.
cortex
The largest region of a hair is the
cortex
statements that describe calluses.
-Develop in areas subject to heavy friction or pressure -Are localized thickenings in the stratum corneum
the factors that influence hair color.
-genetic -melanocyte activity -melanin deposition
all of the components of the dermis.
-nerve fibers -blood vessels -glands -fibers
In humans, what locations do not typically have hair?
-nipples -palms of hands and soles of feet -lips
The dermis contains receptors that detect ______.
-pain -touch -variations in temperature -changes in pressure
statements that describe the function of sebum.
-prevents the drying of the skin surface -protects against some bacteria
Identify the functions of the integumentary system.
-resistance to infection -thermoregulation -sensation of environmental stimuli
terms that describe the major regions of a hair.
-shaft -root -bulb
The functions of vitamin D include ______
-stimulating the uptake of calcium and phosphate from the intestines -promoting calcium and phosphate release from bones -reducing calcium loss from kidneys
Variations in skin color are determined by
-the amount of melanin produced -the distribution of melanosomes
properties that help the skin prevent microorganisms and other foreign substances from entering the body.
-the lack of blood vessels in the epidermis limits access to central circulation -multiple layers of dead cells make it difficult for pathogens to enter -secretions from skin glands produce an environment unsuitable for some microorganisms
The subcutaneous tissue is largely composed of adipose tissue and _____ tissue
loose connective
The two major glands of the skin are the
oil and sweat glands
The medulla contains
soft keratin
Muscle contraction during exercise increases body temperature which leads to the release of body heat via ______.
the dilation of blood vessels in the dermis
Near the time of birth, lanugo hair is replaced by _____ hairs which are short, fine, and usually unpigmented, and _____ hairs which are typically long, coarse, and pigmented.
vellus, terminal