Connect 6
What causes "goose bumps"?
Contraction of the piloerector muscles
stratum corneum
Dead keratinocytes exfoliate from the skin surface.
Which of the following describes thick skin?
It has sweat glands but no hair follicles or sebaceous glands.
stratum granulosum
Keratin filaments are bound together to form waterproof bundles. Keratinocytes die.
stratum spinosum
Mitosis ceases. Keratinocytes are pushed upward as new cells are added below them.
What is the function of melanin in the skin?
Protection from UV light
stratum basale
Stem cells divide and new keratinocytes are produced.
Which of the following best describes the dermal papillae?
The upward projections of the dermis at the dermis-epidermis boundary
the hair, nails, and cutaneous glands are known as
accessory organs
Name the stage in which scalp follicles spend 90% of the time.
anagen
Programmed cell death is ______.
apoptosis
Name the muscle that extends from dermal collagen fibers to the connective tissue root sheath of a hair follicle.
arrector pili
What is the shrinkage of a tissue called?
atrophy
stage of the hair growth cycle, mitosis ceases and the sheath cells below the bulge die.
catagen
Cells in the epidermis are nourished by blood vessels located in which of the following?
dermis
Most cells undergoing apoptosis are ______.
destroyed by macrophages
Keratinocytes are the most numerous type of skin cells. Where are they located?
epidermis
Growth of a tissue due to an increase in cell number is called
hyperplasia
Growth of a tissue through cellular enlargement is called
hypertrophy
Name the connective tissue layer that lies between the skin and the deeper muscle or other tissue.
hypodermis
is located deep to the dermis and is not part of the skin.
hypodermis
Thermoregulation, sensory reception, vitamin D production and protection are all functions of the
integumentary system
Flat or concave nails are a clinical sign of which of the following?
iron deficiency
Stem cells have various degrees of developmental _________, or diversity of mature cell types to which they can give rise.
plasticity
Tight junctions located between keratinocytes in the skin play an important role in which of the following?
preventing water loss
Pheomelanin is a form of melanin that has which of the following colors?
reddish yellow
Identify the two ways that tissue can be repaired.
regeneration and fibrosis
What are cells that have the potential to differentiate into one or more types of mature functional cells called?
stem cells
deepest layer of epidermis
stratum basale
Skin is classified as thick or thin based on the thickness of which layer?
stratum corneum
most superficial layer of epidermis
stratum corneum
third most superficial layer of epidermis
stratum granulosum
Second most superficial layer of epidermis
stratum lucidum
second deepest layer of epidermis
stratum spinosum
Name the stage of the hair growth cycle that occurs when hair goes into a resting period.
telogen