Bios 251 Final Exam: Questions & Detailed Answers
Functions of the skin Right Ans - Protection, Thermoregulation, Cutaneous
Sensation, Vitamin D synthesis, Blood Reservoir, Excretion and Absorption.
Layers of skin Right Ans - epidermis and dermis
What are the major cell types in the epidermis? Right Ans - keratinocytes
and melanocytes, langerhans, merkel cells
What are keratinocytes? Right Ans - Epidermal cells composed of keratin,
lipids, and other proteins.
Produce keratin, help waterproof the skin.
What are melanocytes? Right Ans - Cells that produce skin pigment
granules in the basal layer and produce melanin
What are Langerhans cells? Right Ans - Specialized dendritic cells found in
the skin. participate in immune response against microbes. they also help
alert cells of the immune system of microbes that are invading
What are Merkel cells? Right Ans - attach to sensory neurons. in the
deepest layer
thick skin vs thin skin Right Ans - Thick: palms of hands and soles of feet,
has all five stratum
Thin: Covers rest of the body, does not have visible stratum lucidum, only has
4 stratum
thick skin Right Ans - 5 layers- come lets get sun burnt
Layers of the epidermis (superficial to deep) thick skin Right Ans - stratum
corneum, stratum lucidum, stratum granulosum, stratum spinosum, stratum
basale
stratum corneum Right Ans - outermost layer of the epidermis, which
consists of flattened, keratinized cells. no longer contain a nucleus
,stratum lucidum Right Ans - a layer of the epidermis found only in the thick
skin of the fingers, palms, and soles
clear flat dead keratinocyters that contain large amounts of kertain and
thickened plasma membranes
stratum granulosum Right Ans - keratinocytes are undergoing apoptosis
distinctive feature of keratohyalin
stratum spinosum Right Ans - a layer of the epidermis that provides
strength and flexibility to the skin
startum basale Right Ans - A single layer of columnar cells (base layer)
undergo cell division
structure include scattered intermediate filaments called keratin intermediate
filaments
regions of dermis Right Ans - papillary and reticular
papillary layer Right Ans - outer layer of the dermis, directly beneath the
epidermis
recticular layer Right Ans - deepest skin layer; contains blood vessels,
sweat and oil glands, and deep pressure receptors called Pacinian corpuscles
accessory structures of the skin Right Ans - hair, skin glands, and nails
Anatomy of Hair Right Ans - shaft, root, follicle, bulb
composed of columns of dead, keratinized epidermal cells bonded together by
extracellular proteins
hair shaft Right Ans - the portion of the hair that projects beyond the skin
hair root Right Ans - The part of the hair contained within the follicle,
below the surface of the scalp.
shaft and root both contain three layers of cells: medulla, cortex, cuticle
hair follicle Right Ans - sac within which each hair grows
, Lanugo Right Ans - fine, soft hair, especially that which covers the body and
limbs of a human fetus or newborn.
vellus hair Right Ans - pale, fine hair; found as children's and adult
women's body hair
hair matrix Right Ans - a germinal layer of cells responsible for the growth
of existing hairs and the production of new hairs when old hairs are shed
hair color is determined by Right Ans - amount and type of melanin
Dark colored hair contains Right Ans - eumelanin (brown and black)
blond hair contains Right Ans - pheomelanin
what glands are associated with the skin Right Ans - sweat glands:
eccrine- temperature control
apocrine- scent gland located in pits, and groin
sebaceous glands: secrete oil or sebum
mammary glands: modified sweat glands that secrete milk
ceruminous glands: produce ear wax, cerumen
sebaceous glands Right Ans - secrete sebum (oil) into the hair follicles
where the hair shafts pass through the dermis
sebum (oil) Right Ans - Gives protection from external factors such as
invasion by certain bacteria
sudoriferous glands Right Ans - glands that secrete sweat to the outside of
the body; also assist in body temperature regulation
eccrine glands Right Ans - glands that produce sweat; found over most of
the body- emotional sweating
Functions of the skin Right Ans - Protection, Thermoregulation, Cutaneous
Sensation, Vitamin D synthesis, Blood Reservoir, Excretion and Absorption.
Layers of skin Right Ans - epidermis and dermis
What are the major cell types in the epidermis? Right Ans - keratinocytes
and melanocytes, langerhans, merkel cells
What are keratinocytes? Right Ans - Epidermal cells composed of keratin,
lipids, and other proteins.
Produce keratin, help waterproof the skin.
What are melanocytes? Right Ans - Cells that produce skin pigment
granules in the basal layer and produce melanin
What are Langerhans cells? Right Ans - Specialized dendritic cells found in
the skin. participate in immune response against microbes. they also help
alert cells of the immune system of microbes that are invading
What are Merkel cells? Right Ans - attach to sensory neurons. in the
deepest layer
thick skin vs thin skin Right Ans - Thick: palms of hands and soles of feet,
has all five stratum
Thin: Covers rest of the body, does not have visible stratum lucidum, only has
4 stratum
thick skin Right Ans - 5 layers- come lets get sun burnt
Layers of the epidermis (superficial to deep) thick skin Right Ans - stratum
corneum, stratum lucidum, stratum granulosum, stratum spinosum, stratum
basale
stratum corneum Right Ans - outermost layer of the epidermis, which
consists of flattened, keratinized cells. no longer contain a nucleus
,stratum lucidum Right Ans - a layer of the epidermis found only in the thick
skin of the fingers, palms, and soles
clear flat dead keratinocyters that contain large amounts of kertain and
thickened plasma membranes
stratum granulosum Right Ans - keratinocytes are undergoing apoptosis
distinctive feature of keratohyalin
stratum spinosum Right Ans - a layer of the epidermis that provides
strength and flexibility to the skin
startum basale Right Ans - A single layer of columnar cells (base layer)
undergo cell division
structure include scattered intermediate filaments called keratin intermediate
filaments
regions of dermis Right Ans - papillary and reticular
papillary layer Right Ans - outer layer of the dermis, directly beneath the
epidermis
recticular layer Right Ans - deepest skin layer; contains blood vessels,
sweat and oil glands, and deep pressure receptors called Pacinian corpuscles
accessory structures of the skin Right Ans - hair, skin glands, and nails
Anatomy of Hair Right Ans - shaft, root, follicle, bulb
composed of columns of dead, keratinized epidermal cells bonded together by
extracellular proteins
hair shaft Right Ans - the portion of the hair that projects beyond the skin
hair root Right Ans - The part of the hair contained within the follicle,
below the surface of the scalp.
shaft and root both contain three layers of cells: medulla, cortex, cuticle
hair follicle Right Ans - sac within which each hair grows
, Lanugo Right Ans - fine, soft hair, especially that which covers the body and
limbs of a human fetus or newborn.
vellus hair Right Ans - pale, fine hair; found as children's and adult
women's body hair
hair matrix Right Ans - a germinal layer of cells responsible for the growth
of existing hairs and the production of new hairs when old hairs are shed
hair color is determined by Right Ans - amount and type of melanin
Dark colored hair contains Right Ans - eumelanin (brown and black)
blond hair contains Right Ans - pheomelanin
what glands are associated with the skin Right Ans - sweat glands:
eccrine- temperature control
apocrine- scent gland located in pits, and groin
sebaceous glands: secrete oil or sebum
mammary glands: modified sweat glands that secrete milk
ceruminous glands: produce ear wax, cerumen
sebaceous glands Right Ans - secrete sebum (oil) into the hair follicles
where the hair shafts pass through the dermis
sebum (oil) Right Ans - Gives protection from external factors such as
invasion by certain bacteria
sudoriferous glands Right Ans - glands that secrete sweat to the outside of
the body; also assist in body temperature regulation
eccrine glands Right Ans - glands that produce sweat; found over most of
the body- emotional sweating
