Chapter 5 - Integumentary System

Identify the cell layer indicated by the arrow in this figure of a hair.

Stratum basale

Identify the epidermal layer indicated by the arrow.

Stratum spinosum

In humans, which of the following locations do not typically have hair? Select all that apply.

Lips Nipples Palms of hands and soles of feet

The layers of the skin include the ______ which is the most superficial and the ______ which is deeper.

epidermis and dermis

Describe a hair bulb.

The swollen base of a hair found in the dermis or cutaneous tissue

The highest rate of cell division in the epidermis occurs within the stratum - .

basale

The layer of the epidermis resting directly upon the dermis is the stratum

basale, basal, or germinativum

Select the terms that describe the major regions of a hair. Select all that apply.

bulb, root, shaft

Name the three parts of a hair.

bulb, shaft, root

In skin subjected to friction or pressure, the number of layers in the stratum corneum greatly increases to produce a thickened area called a(n) - .

callus

The cells in the most superficial layer of the skin are dead because _______.

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

The _______ forms the bulk of a hair.

cortex

The largest region of a hair is the _____.

cortex

What are the three concentric regions of the hair from the outside to the inside?

cuticle, cortex, medulla

Cells in the stratum spinosum are nourished by blood vessels located in the ______.

dermis

In humans, palmar and plantar surfaces of the hands and feet typically ______.

do not have hair

Keratinocytes are the most numerous cells found in the ______.

epidermis

The most superficial layer of skin is the _____.

epidermis

Thermoregulation, sensory reception, vitamin D production and protection are all functions of the ______.

integumentary system

Keratin, a protein associated with the skin, is produced by ______.

keratinocytes

The epidermal cells that produce a protein that increases the durability of the skin are ______.

keratinocytes

The majority of cells found in the epidermis are ______.

keratinocytes

All of the following structures provide support or strength to the stratum basale EXCEPT ______.

lamellar bodies

By the fifth or sixth month of fetal development, delicate, unpigmented hair called - has developed and covers the fetus.

lanugo

Select all of the components of the dermis.

-Glands -Blood vessels -Nerve fibers -Fibers

Select the statements that are true of the stratum basale but not of any other layer of the epidermis.

-Melanin is produced only in this layer -The cells of the stratum basale are bound to the basement membrane with hemidesmosomes. -The keratinocytes of the stratum basale have the highest rate of mitotic division when compared to any other layer of the epidermis.

Select the factors that influence hair color.

-Melanocyte activity -Melanin deposition -Genetics

Select the regions that are composed of loose connective tissue.

-Papillary layer of dermis -Subcutaneous tissue or hypodermis

Indicate the statements that describe the function of sebum.

-Prevents the drying of the skin surface -Protects against some bacteria

Select the statements that describe calluses.

Are localized thickenings in the stratum corneum Develop in areas subject to heavy friction or pressure

Consider both vellus and terminal hair. Name a characteristic they share.

Both are present on adults.

Which label (A-E) indicates the stratum spinosum?

D

Describe lanugo.

Delicate, unpigmented hair that covers the fetus during development

Which label (A-E) indicates the stratum basale?

E

Choose the components of the dermis.

Fibers, glands, blood vessels and nerve endings

Identify the components of the integumentary system. Select all that apply.

Hair Cutaneous glands Nail Skin

Select the statements that describe melanocytes?

Irregularly shaped cells that produce melanin Cells with long processes that extend between the keratinocytes of the stratum basale and the stratum spinosum

John's parents both have black hair and brown eyes. John has white hair and light blue eyes. What can you conclude?

John is an albino.

Identify the functions of the integumentary system.

Sensation of environmental stimuli Thermoregulation Resistance to infection

The sweat glands are considered _______ skin structures.

accessory

A genetic lack of melanin production causes a condition called

albinism

The primary determinant for skin color is the _______, not the _______.

amount of melanin, number of melanocytes

The skin, its accessory glands, and hair are all part of the ______ system.

integumentary

The medulla contains ______.

flexible soft keratin

The swollen portion at the base of a hair is called the ______.

hair bulb

An individual that has a higher deposition of melanin in the skin would most likely ____.

have darker skin

The structures that anchor the epidermis to the basement membrane, providing structural support, are _______.

hemidesmosomes

The subcutaneous tissue is largely composed of adipose tissue and _____ tissue

loose connective

At the center of each hair is a loosely arranged core of cells and air spaces. This region is called the ______.

medulla

The center of the hair is called the _____.

medulla

The deposition of which of the following substances is primarily responsible for the color of the skin, hair and eyes?

melanin

The group of pigments known collectively as - is responsible for protecting the genetic material of skin cells from UV damage.

melanin

The cells contributing to skin color are the ______.

melanocytes

Sebaceous glands produce secretion that is characterized as which of the following?

oily

One of the most important functions of melanin is to ______.

provide protection against ultraviolet light from the sun

Select the major glands of the skin

sebaceous glands and sweat glands

Ultimately, all of the epidermal cells originate from ______.

stem cells in the stratum basale

The epidermis is comprised of layers called _______.

strata

All epidermal cells originate from stem cells located within the _______.

stratum basale

Indicate the layer of the epidermis with the highest rate of mitotic division.

stratum basale

The deepest layer of the epidermis is the ______.

stratum basale

Which of the layers of the epidermis produces new keratinocytes and melanin?

stratum basale

List the strata of the epidermis from the deepest layer to the most superficial.

stratum basale, stratum spinosum, stratum granulosum, stratum lucidum, stratum corneum

The most superficial layer of the epidermis is the ______.

stratum corneum

Identify the accessory skin structures. Select all that apply.

sweat glands, nails, hair

Variations in skin color are determined by ______.

the amount of melanin produced the distribution of melanosomes

Near the time of birth, lanugo hair is replaced by _____ hairs which are short, fine, and usually unpigmented, and _____ hairs which are typically long, coarse, and pigmented.

vellus and terminal