Chapter 6: The Integumentary System

Which of the following describe functions of skin?

- It begins the process of vitamin D synthesis. - Skin is considered a sense organ. - It acts as an important barrier to water and UV radiation.

The skin functions as an important barrier to which of the following?

- Microorganisms - Ultraviolet radiation - Water

Which type of tissue comprises the papillary layer of the dermis?

Areolar connective tissue

Which of the following are found in the dermis?

-Blood vessels -Fibers -Nerve endings -Glands

Identify the components of the integumentary system.

-Hair -Dermis -Epidermis -Cutaneous glands

Which of the following are factors in determining whether individuals have darker or lighter skin?

-In darker skin, the melanocytes produce more melanin. -In darker skin, the melanin breaks down more slowly.

The stratum basale contains which of the following?

-Macrophages to protect the body -Actively dividing cells -The colored pigment melanin

List the features of skin that minimize bacterial and fungal growth during an infection.

-The acid mantle inhibits microbial growth. -The dryness of the skin inhibits microbial growth.

Arrange the layers of the integumentary system in order, starting with the most superficial layer on top of the list and ending with the deepest layer at the bottom.

1. Epidermis 2. Dermis 3. Hypodermis

The following events occur in the life of a keratinocyte. Place them in chronological order starting with what happens first (top box) and ending with what happens last (bottom box).

1. Stem cells divide to produce new keratinocytes. 2. Mitosis ceases as epidermal cells are pushed upward. 3. Keratinocytes flatten and produce waterproof bundles of keratin filaments 4. Keratinocytes die. 5. Dead keratinocytes flake off the sureface of the skin as dander.

Place these epidermal layers in order, starting with the most superficial layer at the top of the list and ending with the deepest layer at the bottom.

1. stratum corneum 2. stratum lucidum 3. stratum granulosum 4. stratum spinosum 5. stratum basale

The pH of the skin surface is between which of the following values?

4-6

The skin makes up what percentage of the body weight?

8

Which describes keratin?

A protein produced in cells of the epidermis

Which of the following describes the stratum basale?

A single layer of cuboidal stem cells and melanocytes resting on a basement membrane

The _____ mantle is a thin, protective film on the skin that has a pH between 4-6.

Acid

Which term refers to the protective film found on skin that is involved in bacterial protection?

Acid mantle

The hypodermis primarily consists of which type of tissue?

Adipose tissue

Mechanical stress from manual labor accelerates keratinocyte multiplication. This results in formation of ______ or corns on the hands or feet.

Callus

Melanocytes

Cells that produce the dark pigments that act as a UV shield

Keratinocytes exfoliate from the epidermal surface as tiny specks called ______ .

Dander

Stratum corneum

Dead keratinocytes exfoliate from the skin surface.

Which term refers to the wavy upward projections at the boundary of the dermis and epidermis?

Dermal papillae

Name the branch of medicine that deals with the integumentary system.

Dermatology

The branch of medicine that deals with the integumentary system is called .

Dermatology

Cells in the epidermis are nourished by blood vessels located in which of the following?

Dermis

Hair follicles and nail roots are embedded in which of the following layers of the skin?

Dermis

Sensory receptors in the dermis and epidermis contribute to which function of the skin?

Detecting changes in the environment

Why are the cells in the stratum corneum dead?

Epidermal cells die as they move away from their nutrient supply in the dermis.

Keratinocytes

Epidermal cells that produce keratin

Keratinocytes are the most numerous type of skin cells. Where are they located?

Epidermis

Which two distinct layers make up the skin?

Epidermis and dermis

The skin is composed of which of the following?

Epidermis and dermis only

Which cools the skin?

Evaporation of sweat

Which term refers to the shedding of skin cells?

Exfoliation

True or false: Dendritic cells originate in the stratum basale.

False

True or false: The epidermis is highly vascular.

False

True or false: The stratum corneum is the thickest epidermal layer in thin skin.

False

Which of the following are located in the dermis?

Fibers, glands, blood vessels and nerve endings

Which of these structures is covered by thin skin?

Forearm

Which are accessory organs of the integumentary system?

Hair, nails, and cutaneous glands

Name the connective tissue layer that lies between the skin and the deeper muscle or other tissue.

Hypodermis

Subcutaneous injections are administered into which highly vascular tissue layer?

Hypodermis

The ______ is located deep to the dermis and is not part of the skin.

Hypodermis

Dendritic cells

Immune cells that guards against pathogens that penetrate into the skin

The _______ system consists of the skin and its accessory organs.

Integumentary

Thermoregulation, sensory reception, vitamin D production and protection are all functions of which body system?

Integumentary

Which of the following is true about the most superficial layer of the skin?

It contains abundant keratin.

Which of the following describes thick skin?

It has sweat glands but no hair follicles or sebaceous glands.

Stratum granulosum

Keratin filaments are bound together to form waterproof bundles. Keratinocytes die.

Name the coarse dark-staining granules found in the stratum granulosum.

Keratohyalin granules

The acid ______ is the protective film that gives skin its slight acidity.

Mantle

Which feature of the skin protects the body from UV damage?

Melanin deposited in keratinocytes

The five types of cells found in the epidermis are stem cells, keratinocytes, tactile cells, dendritic cells, and ______ .

Melanocytes

Which cells produce the brown to black pigment found in skin?

Melanocytes

Stratum spinosum

Mitosis ceases. Keratinocytes are pushed upward as new cells are added below them.

Which of these is covered by thick skin?

Palms

In which areas of the body is the dermis the thickest?

Palms and soles

The dermis consists of two zones. The more superficial of the two is called the _____ layer.

Papillary

Tight junctions located between keratinocytes in the skin play an important role in which of the following?

Preventing water loss

Which of the following is an example of the non-verbal communication function of the skin?

Reddening of the skin (blushing) when embarrassed

The deepest layer of the dermis is called the _____ layer.

Reticular

Which of the following is one of the important functions of the skin?

Sensing changes in the environment

Tactile cells are responsible for which of the following?

Sensing touch

Tactile cells

Sensory receptors for touch

What is the body's largest and heaviest organ?

Skin

Stratum basale

Stem cells divide and new keratinocytes are produced.

A splinter penetrates to the deepest layer of the epidermis on your hand. What is this layer called?

Stratum basale

Actively mitotic cells are found in which layer of the epidermis?

Stratum basale

Skin is classified as thick or thin based on the thickness of which layer?

Stratum corneum

Which epidermal layer is structured to resist abrasion, penetration, and water loss?

Stratum corneum

Which layer of the epidermis is no longer mitotic and contains dark staining clusters of keratohyalin?

Stratum granulosum

Cells in which epidermal layer contain the protein eleiden?

Stratum lucidum

Which epidermal stratum is the thickest layer in thin skin?

Stratum spinosum

The epidermal water barrier is a layer of lipids located between which two layers?

Stratum spinosum and stratum granulosum

The stratum lucidum contains which of the following?

The clear protein eleidin

John clenches his pen firmly against his finger when he takes notes in class. This repeated pressure on his finger has resulted in which of the following?

The formation of a callus

Why are injections frequently administered into the hypodermis?

The subcutaneous tissue is highly vascular.

Which of the following best describes the dermal papillae?

The upward projections of the dermis at the dermis-epidermis boundary

Which skin type covers the palms, soles, and surfaces of the fingers and toes?

Thick skin

Tactile cells are receptors for which of the following?

Touch

True or false: The skin, its accessory glands, and hair are all part of the integumentary system

True

True or false: Vasoconstriction of blood vessels in the skin is one mechanism used by the body to conserve heat.

True

Stem cells

Undifferentiated cells that divide and give rise to keratinocytes

What happens when the body is chilled?

Vasoconstriction of blood vessels in the skin

Which of the following describes blushing?

Vasodilation of blood vessels

The skin plays an important role in the synthesis of which of the following?

Vitamin D

Which of these functions are impaired in burn patients?

Vitamin D production

The presence of a layer of lipids between the stratum spinosum and stratum granulosum facilitates which of the following?

Water retention

Where is the hypodermis located?

beneath the dermis

The papillary layer of the dermis is especially rich in ______.

blood vessels

_______ is composed of clumps of dander stuck together by sebum and is usually found on the scalp.

dandruff

The skin layer that has the hair follicles and nail roots embedded in it is the ______ .

dermis

Dead keratinocytes flake off from the surface of the epidermis as small white specks called dander. This process is called _____ .

exfoliation

Keratinocytes synthesize ______.

keratin

The epidermis is a barrier to ultraviolet rays, blocking much of the cancer-causing radiation from reaching the nuclei of cells called ______.

keratinocytes

_____ cells are found in two of the epidermal layers and serve an immune function.

langerhans

The most superficial layer of the epidermis is the ______.

stratum corneum

In the process of thermoregulation, cutaneous nerve endings monitor the _____ of the body surface.

temperature