Transcript Exercise 5 -- Skin - People Server at UNCW

HISTOLOGY REVIEW
The Skin
Dr. Tim Ballard
Department of Biology and Marine Biology
Skin – general features
Human skin – H&E – 10x objective
epidermis
dermis
The arrowheads indicate the position of the basement membrane, separating
the keratinized stratified squamous epithelium from the dermis below.
Skin (thin) - epidermis
Human skin – H&E – 40x objective
stratum corneum
stratum granulosum
stratum spinosum
stratum basale
This is a section of thin skin, so the stratum lucidum is not present.
Skin (thin) - epidermis
Human skin – H&E – 40x objective
stratum corneum – multiple layers of dead
squamous cells filled with keratin
stratum granulosum – several layers of living
cells accumulating granules of keratohyaline
stratum spinosum – cells receiving
melanin from melanocytes and
moving towards the surface
stratum basale – mitotic cells giving rise to the
keratinizing system with melanocytes scattered
about
To identify a melanocyte in the stratum basale, look for granules of brownblack pigments in and around cells in this layer.
Skin - dermis
Pig skin – H&E – 10x objective
epidermis
dermal papilla
papillary dermis
dermis
reticular dermis
The reticular dermis has a looser arrangement of fibers than does the papillary
dermis.
Skin – dermis
Human skin – H&E – 4x objective
epidermis
papillary dermis
dermal papilla
reticular dermis
dermis
sweat glands
In this section the coiled tubular portions of eccrine sweat glands are seen in
the reticular dermis.
Skin – eccrine sweat glands
Human skin – H&E – 4x objective
sweat gland duct moving
towards the surface
secretory portions
of sweat glands
Eccrine sweat glands are simple coiled tubular glands. The secretory portion
lies deep in the dermis. The duct is a straight tube that opens on the surface.
Skin – sebaceous glands
Lip – H&E – 4x objective
epidermis
hair follicles
sebaceous glands
Sebaceous glands are oil (sebum) glands of mammalian skin, always associated
with hair follicles.
Skin – sebaceous glands
Lip – H&E – 20x objective
hair follicles
sebaceous gland
The gland is formed as a sac of cells that opens into a hair follicle. The
secretion is called sebum.
end