Anatomy and Physiology Integumentary System

List the five parts of the integumentary system

skin

hair

oil and sweat glands

nails

sensory receptors

What are the six functions of the

integumentary systems

regulated body temperature

stores blood

protects body from external environment

detects cutaneous sensations

excretes and absorbs substances

synthesizes vitamin D

medical specialty that deals with the

diagnosis and treatment of

integumentary system disorders

dermatology

A

Epidermal Ridges

B

Hair shaft

C

Papillary Plexus

D

Free Nerve Ending

E

Epidermis

F

Papillary Region

G

Reticular Region

H

Dermis

I

Subcutaneous layer

J

Vein

K

Artery

L

Cutaneous plexus

M

Adipose Tissue

N

Sensory Nerve

O

Pacinian Corpuscle

(Lamellated Corpuscle)

P

Apocrine Sweat Gland

Q

Eccrine Sweat Gland

R

Hair Root

S

Hair Follicle

T

Arrector Pili Muscle

U

Meissner Corpuscle

(Corpuscle of Touch)

V

Sebaceous Gland

(oil gland)

W

Sweat Pore

X

Capillary Loop

Meissner corpuscle

Y

Dermal Papillae

Pacinian Corpuscle (Lamellated corpuscle)

Dermis

1

Pores

3

Papillary Region

4

Eccrine Sweat Duct

6

Sebaceous Gland

(oil gland)

7

Hair Root

8

Hair Follicle

9

Eccrine Sweat Gland

10

Epidermis

11

Papillary Region

12

Reticular Region

The yellow box

Epidermal Ridge

1

2

1. Epidermal Ridge

2. Corpuscle of touch (Meissner)

another name for skin

cutaneous membrane

how does the weight of the skin

compare to the weight of an entire adult human body?

7% of an adult body weight

what are the two main parts of the skin?

epidermis

dermis

dermis is composed of what kind of

tissue?

connective tissue

epidermis is composed of what kind of tissue?

epithelial tissue

why does a paper cut usually not bleed?

The epidermis is avascular

fibers from the dermis anchor skin to which layer?

is that layer part of the skin?

the layer is composed of what kind of tissue?

hypodermis or subcutaneous layer (subQ layer)

it is not part of the skin

areolar and adipose tissue

the hypodermis is connected to what tissue?

fascia (connective tissue around

muscles and bones)

what three things can be found in the subcutaneous layer?

adipose tissue

large blood vessels

pacinian corpuscles

epidermis is composed of what kind of tissue?

keratinized stratified squamous

epithelium

what four types of cells make up the epidermis?

keratinocytes

melanocytes

Langerhans cells

Merkel cells

what two things are produced by

keratinocytes?

what are their functions?

the protein keratin provides strength

lamellar granules provides a

water-repellant sealant

what is produced by melanocytes?

what is its function?

melanin

it gives skin its color and prevents

damage from UV light

what is the function of Langerhans cells?

activate immune responses against

microbes that invade the skin

what is the least common epidermal cell?

what is its function

Merkel cells

make up Merkel discs that sense touch

what are the four layers of the

epidermis in thin skin?

stratum basale

stratum spinosum

stratum granulosum

stratum corneum

what additional layer is found in the epidermis in thick skin?

stratum lucidium

describe the stratum basal

a single layer of cuboidal or columnar

keratinocytes including stem cells

located deepest

melanocytes and merkel cells are scattered throughout

what are the three types of skin graft and where does the tissue come from for each?

autograft - skin comes from the person

receiving the graft

isograft - skin comes from a twin

autologous skin transplant - keratinocytes from the person

receiving the graft are cultured and the

produced skin is used

describe the stratum spinosum

keratinocytes arranged in 8 - 10 layers, becoming more flattened as they become more superficial, the keratin proteins are coarser and tightly join

adjacent cells in desmosomes.

Langerhans cells and projections of melanocytes are also present in this layer

describe the stratum granulosum

3 - 5 layers of flattened keratinocytes undergoing apoptosis, having degenerating nuclei and organelles as they move away from the dermal blood vessels

lamellar granules fuse with the plasma membrane and release lipids for water-repellant sealant

describe the stratum lucidum

4 - 6 layers flattened, clear, dead

keratinocytes that contain large amounts of keratin and thickened

plasma membranes

describe the stratum corneum

25 - 30 layers of flattened, dead

keratinocytes. The cells are extremely thin and flat and no longer contain nucleus or organelles; they only contain keratin. The cells overlap like scales on a snake.

an abnormal thickening of the stratum corneum

callus

1

stratum corneum

2

stratum granulosum

3

stratum lucidum

4

stratum spinosum

5

stratum basale

melanocyte

langerhans cell

A

B

C

D

A keratinocyte

B melanocyte

C Langerhans cell

D Merkel cells

the process in which cells mover from one epidermal layer to the next, accumulating more keratin as they go

keratinization

On average, how long does it take cells formed in the stratum basal to rise to the surface and become sloughed off?

4 - 6 weeks

describe the composition of the dermis

dense irregular connective tissue

containing collagen and elastic fibers

which is thicker, the dermis or

epidermis?

dermis

dried, treated dermis

leather

what kind of cells are found in the

dermis?

a few cells, predominantly fibroblasts, some macrophages, and a few adipocytes near the subQ layer

what are the two layers of the dermis?

papillary region (1/5 thickness)

reticular region (4/5 thickness)

what fibers make up the papillary

region?

thin collagen and elastic fibers

small, nipple shaped structures that project into the undersurface of the

epidermis

dermal papillae

what structures can be found in dermal papillae?

all contain capillary plexus

some contain Meissner corpuscles

some contain free nerve endings

what fibers make up the reticular

region?

thick collagen fibers and some coarse elastic fibers

what is different about the collagen fibers in the reticular region when

compared to the papillary region?

In the reticular region, collagen fibers are more course and arranged in a

netlike manner, creating a greater

resistance to stretching

what things can be found in-between the fibers of the reticular region?

blood vessels

nerves

hair folicles

sebaceous glands

sudoriferous glands

the ability to stretch

extensibility

the ability to return to original shape after stretching

elasticity

a series of ridges and grooves on the surfaces of palms, finger, soles, and toes

epidermal ridges

what creates the surface features of the epidermal ridges?

downward projections of the epidermis into the dermis between the dermal papillae of the papillary region

what causes fingerprints?

ducts of sweat glands open o the tops of epidermal ridges as sweat pores and this sweat is what forms fingerprints

what are the two functions of the

epidermal ridges?

1. increases the surface contact between the dermis and epidermis, allowing

nutrition of the dermis

2. strengthens the junction between the

dermis and epidermis

regions of the skin where the collagen fibers have a predominant direction

tension lines

(lines of cleavage)

what ware the two types of melanin and what color do they produce?

pheomelanin (yellow to red)

eumelanin (brown to black)

where are the most melanocytes found in the human body?

epidermis of the penis

nipples of the breast

areolae (area around the nipples)

face

limbs

mucous membranes

what causes the color differences

between people?

the number of melanocytes is

consistent between people

color differences are related to the amount of pigment produced by the melanocytes

melanocyte patches present in young people

freckles

accumulation of melanin due to age

liver spots