Another name for the skin is the ______ membrane.

Cutaneous

Reticular layer of Dermis

Dense irregular connective tissue surrounding blood vessels, hair follicles, nerves, sweat glands, and sebaceous glands

Papillary layer of Dermis

Composed of areolar connective tissue; contains dermal papillae

subcutaneous layer (hypodermis)

Beneath dermis; insulating layer
mainly adipose connective tissue
Not considered part of the skin

Many cells in the epidermis produce cholecalciferol when exposed to ______.

UV light

TRUE or FALSE: Metabolic regulation is a function of the integument.

TRUE

Integumentary Functions

Protection
Prevent water loss/gain
Temperature regulation
mMetabolic regulation
Immune Defense
Sensory reception
Secretion

layers of epidermis (deep to superficial)

1. stratum basale
2. stratum spinosum
3. stratum granulosum
4. stratum lucidum (only in thick skin)
5. stratum corneum

Transepidermal Water Loss (TEWL)

when interstitial fluids slowly escape through the epidermis to the surface, where they evaporate into the surrounding air

Langerhans cells (dendritic cells)

- Star shaped cells
- specialized phagocytes and become antigen processing cells after capturing and processing things like microbial antigens in skin
-Found in the stratum spinosum of the epidermis

Body temperature is influenced by two structures located in the dermis, ______ and ______.

blood vessels, sweat glands

tactile cells (merkel cells)

Large specialized epithelial cells that stimulate sensory nerve endings when distorted by touch or pressure
- Found in the stratum basale of the epidermis

The integument accounts for about _____% of the body weight.

8

The substances that make sweat feel gritty are ______.

Waste substances

Some cells in the epidermis produce cholecalciferol. This substance travels to the kidneys where it is transformed into ______, also known as Vitamin D.

Calcitrol

There are no blood vessels in the epidermis. The term for lack of blood vessels is ______.

Avascular

The skin is said to be ______ because some materials are able to pass through it.

selectively permeable

______ cells are derived from white blood cells that phagocytize pathogens in the epidermis.

Dendritic/ langerhans cells

Which describes the tissue type of the epidermis?

Keratinized stratified squamous epithelium

When compressed, tactile cells release chemicals that stimulate ______ endings in the dermis.

Sensory Nerve endings

The spiny appearance of stratum spinosum cells is primarily due to the tenacious nature of _____, which function to hold these non-dividing cells together.

Desmosomes

In the layer of the epidermis called the stratum ______, the process of keratinization begins.

Granulosum

What layer of the epidermis is only found in thick skin?

stratum lucidum

what layer of the epidermis has dividing keratinocytes?

stratum basale

PIgment producing cells of the epidermis are ______.

Melanocytes

Most cells of the stratum spinosum are ______.

Keratinocytes

Keratinocytes of the epidermis are usually present for about ____ week(s).

4

The stratum granulosum is just superficial to the ______.

Stratum spinosum

True or false: The epidermis exhibits variations among different body regions within a single individual, as well as differences between individuals.

TRUE

During the process of keratinization, ______ disintegrate and the cells start to die. Also their membranes become thicker and less permeable.

Organelles

The epidermis of thick skin ranges from 0.4mm to ______ mm thick.

0.6mm

Melanosomes are transferred to keratinocytes in the stratum basale via the process of ______ or exocytosis.

Phagocytosis

The epidermis of thin skin ranges in thickness from ______ millimeters to ______ millimeters thick

.075, 0.150

The keratinocytes within stratum lucidum are flattened and filled with the protein ______, an intermediate product in the process of keratin maturation.

Eleidin

Which pigments contribute to skin color?

melanin, carotene, hemoglobin

The cells of the stratum corneum contain large amounts of the protein called ______.

Keratin

Melanin is transferred in membrane-bound vesicles from _____ to keratinocytes in the stratum basale.

malanocytes

There are three main variations in the epidermis. These variations are ______, ______, and skin markings.

thickness, coloration

All people, of all skin tones, have about the same number of melanocytes.

True

Skin is classified as either thick or thin based on two parameters. These are the number of ______ in the epidermis and the relative thickness of the epidermis, rather than the thickness of the entire integument.

Layers

The two types of connective tissue in the dermis are ______.

areolar and dense irregular

______ skin contains the following accessories: nails, hair follicles, sweat glands, and sebaceous glands.

Thin

The ______ layer of the dermis contains areolar connective tissue and dermal papillae.

Papillary

There are two types of melanin, _________ and pheomelanin, together they produce various ratios of yellow, reddish, tan, brown, and black shades.

Eumelanin

The amount of melanin in the skin is determined by _____.

heredity and ultraviolet light exposure

The specific orientation of ______ fiber bundles in the dermis is a result of the direction of applied ______ during routine movements.

Collagen, Stress

The predominant type of protein fiber found in the dermis is ______.

Collagen

The connective tissue layers of the dermis contain cells called ______.

Fibroblasts

Nerve fibers in skin control

blood flow
gland secretions
sensory receptors

he dermal papillae interlock with deep projections of the epidermis called ______.

epidermal ridges

The main structural components of the reticular layer is primarily a network of ______ fibers that extend internally from the reticular layer of the dermis into the underlying subcutaneous layer.

Collagen

Which are functions of the subcutaneous layer?

Energy reservoir
Protection
Thermal insulation

______ cuts to the lines of cleavage often results in slow healing and increased scarring.

Perpendicular

Stretch marks are also called ______.

striae

Nails are derived from the same type of cells that produce the stratum ______ layer of the epidermis.

Corneum

Nerve fibers in the skin monitor sensory receptors in the ______.

epidermis and dermis

Extending from the hair follicle to dermal papillae are muscles called _____.

arrector pili

The subcutaneous layer is also known as the ______ or superficial fascia.

hypodermis

In children, ______ is the primary human hair and is found on most of the body.

Vellus

The accessory organs of the epidermis are hair, ______, ______ glands and sweat glands.

nails, sebaceous

Which type of hair is associated with the fetus?

Lanugo

Each nail plate consists of a pinkish nail ______ and a distal whitish free ______.

Body, Edge

_____ hair is the type of hair that grows on the scalp, and is also the hair of eyebrows and pubic region. In men, it also grows on the face.

Terminal

The color of hair is the result of?

melanin production

The three recognizable zones along the length of a hair are

bulb, root, shaft

Sebaceous glands produce (an) ______ material that coats hair shafts and the epidermal surface

Oily

Extending from the dermal papillae to the mid-region of the hair follicles are thin ribbons of smooth muscle that are collectively called the ______ muscles.

arrector pili

In anatomy, a single hair is also called a(n) ______.

Pilus

functions of hair

protection, heat retention, sensory reception, visual identification

Exocrine Glands in Skin

sebaceous glands and sweat glands

exocrine glands

gland that releases its secretions through tubelike structures called ducts

types of sweat glands

apocrine and merocrine

apocrine sweat glands

produce true sweat plus fatty substances and proteins; found in the axillary (armpit) and anogenital areas of the body

merocrine sweat glands

coiled tubular glands that discharge their secretions directly onto the surface of the skin

location of apocrine sweat glands

axillae and external genitalia

location of merocrine sweat glands

Distributed throughout body/ everywhere

location of sebaceous glands

everywhere except palms and soles / associated with hair follicles

location of ceruminous glands

only in external acoustic meatus

ceruminous glands

modified sweat glands, located in external ear canal, secretes cerumen (earwax)

mammary glands

specialized sweat glands that secrete milk

The skin houses two types of general exocrine glands, which are ________ glands and _______ glands.

Sweat and sebaceous

The connective tissue root sheath of hair originates from the ______.

Dermis

The epithelial tissue root sheath of hair originates from the ______.

epidermis

Dermis layers (superficial to deep)

papillary layer and reticular layer

The secretion from merocrine sweat glands are carried to the surface of the epidermis via ______. The secretions of apocrine sweat glands are carried into __________.

sweat ducts/hair follicles

Exocrine glands of skin and their secretion/function

Apocrine: secrete proteins and lipids
Merocrine: function in thermoregulation and excretion
Sebaceous: lipid material called sebum

The most numerous and widely distributed sweat glands in the body are ______.

merocrine sweat glands

The apocrine sweat glands become active and produce secretory product after ______.

puberty

In first degree burns, the healing time averages about _____ days, and typically no scarring results.

3-5 days

The secretion produced by apocrine sweat glands is viscous, cloudy, and composed of ______ that are acted upon by bacteria, producing a distinct, noticeable odor.

Proteins and lipids

Second-degree burns involve the ______ and part of the ______.

epidermis, dermis

Sebaceous glands are classified as ______ glands that discharge an oily, waxy secretion called ______.

Holocrine, sebum

holocrine glands

Exocrine glands whose secretions are made up of disintegrated cells

apocrine glands

Exocrine glands that have cytoplasm in their secretions

merocrine glands

Exocrine glands that secrete without losing cellular material

Repetitive mechanical stresses applied to the integument stimulate mitotic activity in the ______ cells of the stratum ______.

Stem, basale

In what two ways are damaged skin tissues normally repaired?

Regeneration and Fibrosis

Healing of second degree burns takes approximately ______ weeks, and slight scarring may occur.

2-4 weeks

Third-degree burns involve what layers

epidermis, dermis, and subcutaneous layers

Second-degree burns involve what layers

epidermis and part of the dermis layer

First-degree burns involve what layers

epidermis

When regeneration of damaged skin tissue is not possible, ______ occurs.

fibrosis

True or false: Regeneration in the skin replaces damaged or dead cells with the same cell type and restores organ function.

True