A & P 1 Chapter 6
True or false: The reason the cells of the stratum spinosum have a spiny appearance when viewed under a microscope is due to shrinkage of the cytoplasm.
True; This spiny appearance is how the layer got its name.
Sudoriferous glands
sweat glands
In what ways are cleavage lines in the skin clinically significant?
-Stretching of the skin during pregnancy or extreme weight gain will cause stretch marks along these lines. -They are surgically important because any procedure resulting in a cut perpendicular to a cleavage line may gape and delay healing.
Match the hair structure with its description. 1. Protrudes above the surface of the skin 2. Central axis of the hair 3. Portion of the connective tissue that surrounds the epithelial root sheath 4. Contains the hair; consists of epithelial and dermal root sheaths 5. Expanded knob at the base of the hair root 6. The portion of the hair that is below the surface of the skin 7. Forms the bulk of the hair; consists of cells containing hard keratin 8. Outer layer of the hair; single layer of cells containing hard keratin 9. Mass of epithelial cells within the bulb that produce the hair
1. Hair Shaft 2. Medulla 3. Dermal Root Sheath 4. Hair Follicle 5. Hair Bulb 6. Root 7. Cortex 8. Cuticle 9. Matrix
Migration of a keratinocyte from the stratum basale to the stratum corneum takes about ______ weeks. The dead, keratinized cells usually remain in the exposed stratum corneum layer for an additional ________ weeks. Overall, keratinocytes are present for about ________ month following their formation.
2;2;1
______ layers of keratinocytes comprise the stratum granulosum.
3-5
True or false: Regeneration in the skin replaces damaged or dead cells with the same cell type and restores organ function. True false question.
True; This is the general process of tissue repair.
In the development of embryonic skin, the _________ layer gives rise to the epidermis, and the ___________ gives rise to the dermis.
basal; mesenchyme
Components of the dermis
blood vessels, sweat glands, sebaceous glands, hair follicles, nail roots, sensory nerve endings, smooth muscle tissue
Merocrine Sweat Glands
coiled tubular glands that discharge their secretions directly onto the surface of the skin; main function is thermoregulation
The stratum ______ consists of about 20 to 30 layers of dead, scaly, interlocking keratinized cells.
corneum
The subcutaneous layer is ____________ to the dermis.
deep
The dermis is ______ to the epidermis and contains primarily ______.
deep; collagen fibers
Stratum basale
deepest layer of epidermis; contains mitotic keratinocytes, melanocytes, and tactile cells
In addition to keratinocytes, the stratum spinosum also contains another epidermal cell type called epidermal ______ cells that help to fight infection
dendritic
The main function of melanin pigment is to protect the _________ of keratinocytes from UV radiation.
dna
Fingernails ____________ protect the digits from damage.
do
Nails form on the _______ edges of the fingers and the toes.
dorsal
The keratinocytes within stratum lucidum are flattened and filled with the protein ______, an intermediate product in the process of keratin maturation. Multiple choice question.
eledin; The cells in the stratum lucidum do not yet contain fully formed keratin.
The nails, hair, and exocrine glands of the skin are known as ______.
epidermal appendages
Immune cells found in the epidermis are called
epidermal dendritic cells
The most superficial layer of the integument is the ______.
epidermis
The two distinct layers of the integument consist of a layer of stratified squamous epithelium called the ______ and a deeper layer of areolar and dense irregular connective tissue called the ______.
epidermis; dermis
A mild sunburn with no blistering is an example of a ______-degree burn.
first
The subcutaneous layer is also known as
hypodermis or superficial fascia
The connective tissue fibers that extend from the dermis into the subcutaneous layer help ____________ the skin in relation to underlying structures.
insulation
The cells of the stratum corneum contain large amounts of the protein ______.
keratin
Within the stratum, granulosum begins a process called ______.
keratinization
Classify the tissue type of the epidermis
keratinized stratified squamous epithelium
The most numerous cells of the epidermis are_________, and the protein they produce is called________-
keratinocytes; keratin
Periderm
layer of cells covering the developing embryonic epithelium
Mesenchyme
layer of embryonic cells that develops into the dermis
The first three strata of the epidermis consists of ______ keratinocytes and the most superficial strata contain ______ keratinocytes.
living; dead
In thick skin, there is an extra layer of epidermal cells. This layer is called the stratum ______.
lucidum
Scattered among the keratinocytes of the stratum basale are pigment-producing cells called ______.
melanocytes
The two types of sweat glands in the skin are
merocrine and apocrine
During the process of keratinization, the cell's _____ and organelles disintegrate and the cells start to die.
nucleus
Stratum Corneum
outermost layer of epidermis; contains flat and dead keratinocytes
Papillary Layer of Dermis
outermost layer of the dermis, directly underneath the epidermis; composed of areolar connective tissue
Apocrine Sweat Glands
produce true sweat plus fatty substances and proteins; found in the axillary (armpit) and anogenital areas of the body;
Fibrous tissue is also known as
scar tissue
The subcutaneous layer is usually ________ in women than in men.
thicker
The main functions of the subcutaneous layer
Acts as an energy reservoir. Provides thermal insulation. Protects the body.
Hemangioma
a benign tumor made up of newly formed blood vessels
Stratum lucidum
a layer of the epidermis found only in the thick skin of the fingers, palms, and soles
Stratum granulosum
a layer of the epidermis that marks the transition between the deeper, metabolically active strata and the dead cells of the more superficial strata; keratinization begins
Exocytosis
a process by which the contents of a cell vacuole are released to the exterior through fusion of the vacuole membrane with the cell membrane.
The subcutaneous layer consists of areolar connective tissue and ____________ connective tissue.
adipose
Reticular Layer of Dermis
forms the deeper, major portion of the dermis that extends from the papillary layer to the underlying, subcutaneous layer; consists primarily of dense irregular connective tissue in which fibers surround the main structures of dermis
In the layer of the epidermis called the stratum _________, the process of keratinization begins.
granulosum
Sebaceous Glands
secrete sebum (oil) into the hair follicles where the hair shafts pass through the dermis
Exocrine
secreting externally
Endocrine
secreting internally
When compressed, tactile cells release chemicals that stimulate ______ endings in the dermis.
sensory nerves
Stratum spinosum
several layers of keratinocytes joined by desmosomes; cells contain thick bundles of intermediate filaments made of pre-keratin.
After a stem cell divides in the stratum basale, the resulting daughter cell enters the stratum ______ and it begins to lose its ability to divide.
spinosum
Epidermal dendritic cells are found in which of the following strata?
spinosum granulosum
The connective tissue fibers that extend from the dermis into the subcutaneous layer help ____________ the skin in relation to underlying structures.
stabalize
The layer of the skin from which most new epidermal cells are derived from is the ______.
stratum basale
Nails are derived from the same type of cells that produce the
stratum corneum
The most superficial layer of the epidermis is the ______.
stratum corneum
There are four layers of cells in the epidermis of thin skin. From superficial to deep, these layers are:
stratum corneum stratum granulosum stratum spinosum stratum basale
Nails are a scalelike modification of the ____________ layer of the ____________ .
stratum corneum; epidermis
Which layer of the integument has a small population of immune cells?
stratum spinosum
The skin houses two types of general exocrine glands
sweat and sebaceous
The secretion from merocrine sweat glands is carried to the surface of the epidermis via ______. The secretions of apocrine sweat glands are carried into ______.
sweat ducts; hair follicles
Scattered among the cells of the stratum basale are cells that are sensitive to touch. These sensory cells are called ______.
tactile cells
The delivery of drugs through the skin through the use of an adhesive patch is called _____ administration.
transdermal
The release of water vapor from sweat glands when we are not sweating is a process called______
transpiration
Vernix Caseosa
waterproof protective covering composed of sebum and sloughed off cells
