skin

Place the steps in the production of vitamin D as they occur, starting at the top.

-Production of dehydrocholesterol in skin cell -production of cholecalciferol with the help of sunlight -production of calcittiol in liver and kidney cells

How is melanin protective?

Absorbs UV radiation from sunlight

The dermis consists of two layers: the superficial_____ layer and the deep _____ layer.

Blank 1: papillary Blank 2: reticular

In most areas of the body, the epidermis contains four layers called stratum. basale, stratum ______, stratum________ , and stratum corneum.

Blank 1: spinosum Blank 2: granulosum

Why do the cells of the epidermis die as they are pushed towards the surface of the skin?

They are too far from their nutrient supply.

What is the function of a keratinocyte

To produce a waterproofing protein.

How is melanin protective?

absorbs UV radiation from sunlight

Cancer called cutaneous carcinoma originates with what cell type?

basal

Cell division by cells of the stratum _________replaces the shedding skin cells of the stratum corneum.

basale

Cell division by cells of the stratum _____replaces the shedding skin cells of the stratum corneum.

basale

Within the epidermis, cell division and growth occur in the stratum

basale

Melanocytes are found within the stratum

basale epidermis

In the epidermis of thin skin, where is the stratum spinosum found?

between the stratum basale and stratum granulosum

Lack of a blood supply within the epidermis is the cause for what characteristic of epidermal cells? Multiple choice question.

cells near the skin surface are dead

What are the two protective functions of sebum?

contains an anti-microbial compound prevents water loss

The outermost layers of the epidermis are called the stratum

corneum

Sweat glands consist of coiled tubes that originate in what layer of the skin?

deep dermis

Which of the following are cells found within the stratum spinosum that are responsible for protecting the skin from pathogens?

dendritic cells

The epidermis is avascular (lacks blood vessels). Therefore, oxygen, nutrients, and wastes must diffuse to and from blood vessels found in what region of the skin?

dermis

The papillary and reticular layers are the two layers of the

dermis

Within the skin, the ______ is the thicker layer composed primarily of connective tissue, while the ______ layer is composed of stratified squamous epithelium

dermis; epidermal

Within the skin, the ______ is the thicker layer composed primarily of connective tissue, while the ______ layer is composed of stratified squamous epithelium.

dermis; epidermal

What variation in melanin accounts for the differences in skin tone between individuals?

differences in the amount of melanin produced

What layer of the skin lacks blood vessels?

epidermal layer

Patches of oxidized sweat gland secretion commonly called "age spots" or "liver spots", occur in the ______ as a person ages.

epidermis

The layer of the skin called __________the lacks blood vessels.

epidermis

The skin contains two distinct layers,

epidermis and dermis

List three of the functions of the skin.

excretion of waste materials protective covering regulation of body temperature

Indicate the factors that stimulate melanin production.

exposure to sunlight exposure to X-rays exposure to ultraviolet light

True or false: Skin color is primarily due to a protein in skin cells called keratin.

false

True or false: The number of melanocytes in a person's skin determines how dark their skin tone will be.

false

The secretion released by sebaceous glands are ______ secretions.

fatty

A hair ______ is a tubelike depression from which a hair develops.

follicle

a hair ____is a tubelike depression from which a hair develops.

follicle

What is the tubelike depression from which a hair grows and emerges at the skin surface?

hair follicle

Which of the following are included in the integumentary system?

hair, skin, nails, and sebaceous and sweat glads

Cellular metabolism results in the production of ______ as energy is lost.

heat

The skin and its accessory organs form the

integumentary system

Which statement describes the stratum basale of the epidermis?

it contains cells that are dividing

The scaly appearance of the skin of older individuals results from changes in the protein called ______, found within epidermal cells.

keratin

The process by which epidermal cells begin to harden due to the accumulation of the protein keratin is called

keratinization

Cells in the epidermis that produce keratin are called

keratinocyte

What type of epidermal cell produces the protein keratin?

keratinocyte

Merkel cells in the epidermis respond to _____

light touch

The epidermis of thick skin contains an extra layer called the stratum _________ . This layer is typically lacking in thin skin.

lucidum

The stratum corneum of the epidermis is made of ______.

many layers of tough, tightly packed, dead cells

The primary determinant of skin color is a pigment-protein called

melanin

The substance called is produced in specialized skin cells. It absorbs ultraviolet radiation from sunlight, preventing it from causing mutations in the DNA of skin cells.

melanin

Cutaneous melanomas, a type of skin cancer, originate from specialized epithelial cells called

melanocytes

Specialized epidermal cells called ______produce the pigment melanin.

melanocytes

The pigment melanin is produced by ______ and contributes to the color that is observed in the skin.

melanocytes

Where on the body is thin skin (with four epidermal layers) found?

most body areas except palms and soles

A nail consists of two parts: a visible nail _____ that overlies a nail_____ .

nail plate and nail bed

The ends of fingers and toes are protected by structures called

nails

Where in the body is thick skin, with five epidermal layers, found?

palms of hands and soles of feet

Identify the two layers of the dermis.

papillary layer reticular layer

What are the two protective functions of sebum?

prevents water loss contains an anti-microbial compound

What is the function of dendritic cells found within the stratum spinosum of the epidermis?

protection from pathogens

The oily mixture secreted by sebaceous glands is called

sebum

Which organ protects, regulates body temperature, and excretes wastes?

skin

What effect can exposure to sunlight, UV radiation, and X-rays have on the skin?

stimulate melanin production

The epidermis only contains one type of tissue, namely

stratified squamous epithelium

What class of tissue forms the epidermis of the skin? Multiple choice question.

stratified squamous epithelium

In what layer of the epidermis are the melanocytes found?

stratum basale

The deepest layer of cells in the epidermis, which is nourished by dermal blood vessels, is called the

stratum basale

The production of new skin cells in what layer typically keeps pace with the loss of cells from the stratum corneum?

stratum basale

Where are tactile cells located in the epidermis?

stratum basale

What epidermal layer is found in thick skin, but not in thin skin?

stratum lucidum

What type of gland in the skin consist of coiled tubes that originate in the deeper dermis or superficial subcutaneous layer?

sweat glands

What is keratinization?

the process by which epidermal cells begin to harden

The palms of the hands and the soles of the feet are covered with ______ skin.

thick

Body areas such as the arms and the legs are covered with ______ skin.

thin

True or false: Body heat is a by-product of cellular metabolism.

true

The synthesis of which vitamin begins in the skin?

vitamin D