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