Ch5 Review

Which of these structures is properly matched with its mode of secretion?

A; holocrine

__________ glands are found primarily in the genital and axillary areas.

Apocrine

What is the structure indicated by label E?

a dermal papilla Dermal papillae are projections of the dermis that form indentations in the overlying epidermis.

Layer B is composed primarily of __________.

areolar connective tissue The loose connective tissue within the papillary layer of the dermis is rich in blood vessels and cells that function in the body's defenses.

The hypodermis is ________.

composed primarily of adipose tissue

Pressure receptors, called lamellar (Pacinian) corpuscles, are located in this layer of the integument.

dermal reticular layer

Layers B and C collectively form the __________.

dermis

These are the most abundant epidermal cells.

keratinocytes

A freckle is a concentrated spot of this pigment.

melanin

Name the substance that protects the DNA of rapidly dividing skin cells from the damage caused by ultraviolet rays from the sun.

melanin

Which of the following is not a function of the skin?

synthesizing vitamin C

Which of the following pigments is not involved in determining skin color?

white pigments in skin cells

Which layer is composed primarily of dense irregular connective tissue?

C -

__________ is a yellow-orange pigment found in the stratum corneum and the hypodermis.

Carotene

What is true about the blood supply to the skin?

Epidermis is avascular and dermis is richly vascularized.

This accessory organ of the skin is composed primarily of dead, keratinized cells.

Hair

What is the most common cell type in the epidermis?

Keratinocytes are the primary cells that form the stratified layers of the epidermis.

Vitiligo is a disorder in which the pigmentation of the skin is uneven, resulting in white patches. Recent research suggests that vitiligo might be an autoimmune disorder. Which cells would you expect to be most affected?

Melanocytes

This region of the nail is responsible for nail growth.

Nail Matrix

What is true about both the epidermis and the dermis?

Sensory receptors are present in each. Submit

The portion of a hair that projects from the scalp surface is known as the __________.

Shaft

Keratinase is an enzyme produced by dermatophytes. Which organ and/or structure in the body would these pathogenic fungi tend to proliferate in?

Skin, hair, and nails

Which of these is NOT a function of the layer at D?

The hypodermis does not perform this function. Cells to replace those lost in the epidermis are provided by the basal cells of the epidermis itself.

What is true about apocrine sweat glands?

They are located predominantly in axillary and genital areas.

What is not true about cutaneous glands, hair, and nails?

They are made up entirely of dead cells.

Which of the statements below is true for both eccrine and apocrine glands?

They produce sweat.

All the following are functions of the skin EXCEPT __________.

Vitamin A

The ________ is the structure responsible for goose bumps.

arrector pili

What is the function of structure B?

detection of pressure stimulus The dermis is not associated with fat storage. Note that structure B is connected to a nerve fiber. Structure B is a lamellar (Pacinian) corpuscle that responds to cutaneous contacts involving deep pressure.

The ________ is often referred to as the cuticle of a nail.

eponychium

Skin color can indicate certain disease states. A reddened, flushed face might indicate ________.

hypertension, fever, or embarrassment

Skin color is determined by the degree of oxygenation of the blood and the relative amounts of these two pigments.

melanin and carotene

These cells produce a brown-to-black pigment that colors the skin and protects DNA from ultraviolet radiation damage. The cells are __________.

melanocytes

This layer of the dermis is responsible for fingerprints.

papillary layer

The ducts of __________ glands usually empty into a hair follicle but may also open directly on the skin surface.

sebaceous

These glands are found all over the skin except in the palms of the hands and soles of the feet. They produce an oily substance that lubricates skin and hair.

sebaceous glands

Like all epithelial membranes, the skin has an epithelial layer and a connective tissue layer. The keratinized epithelial and connective tissues are ________.

stratified squamous and dense irregular

From deep to superficial, the layers of the epidermis of thin skin are ________.

stratum basale, stratum spinosum, stratum granulosum, stratum corneum Submit

The cells in this layer of epidermis are dead, and their flat, scale-like remnants are filled with keratin.

stratum corneum

The most superficial layer of the epidermis is the __________.

stratum corneum

This layer of the epidermis contains translucent cells filled with keratin fibrils. It is found only in thick skin.

stratum lucidum

Which of the following terms describes layer D?

subcutaneous The hypodermis ("under the skin") layer is also referred to as the subcutaneous region.

What feature of the prickle cells in layer C causes them to have pointy projections after tissue preparation?

their desmosome attachments Cells typically shrink during tissue preparation, and since these cells are attached by desmosomes, the membranes are pulled slightly outward at the points of cellular attachment.

What is the function of the structure at A?

to lubricate hair and prevent infection Structure A produces sebum, an oily secretion that coats the hairs and prevents infectious agents from penetrating the hair shaft.

Nails originate from the epidermis.

true

Cell division would be most common among cells in which of the labeled layers?

D Cells migrate upwards through the epidermis after being generated by mitosis in the stratum basale.

Which skin-color-associated, pigment-producing cell is located in the labeled layer D?

Melanocytes within the stratum basale produce the pigment melanin, which is deposited within the deeper layers of the epidermis.

Which structure is a type of sweat gland?

Structure C is an eccrine gland, the most abundant type of sweat (sudoriferous) gland.

Which of the following correctly describes a common feature of all structures labeled A through D in the figure?

Structures A, B, C, and D are located in the dermis.