Ch. 5.5 The Dermis

Question 1

What are the two major components of the dermis?

Answer 1

1. Papillary layer
2. Reticular layer

Question 2

Papillary layer

Answer 2

• Consists of areolar tissue
• Contains capillaries, lymphatics, and sensory neurons that supply skin
• Name derived from dermal papillae that project between epidermal ridges.

Question 3

reticular layer

Answer 3

• Deep to papillary layer
• Interwoven dense irregular connective tissue w/ both collagen and elastic fibers
• Bundles of collagen fibers extend superficially into papillary layer and deep into hypodermis
• indistinct boundary

Question 4

the dermis

Answer 4

• Contains all the cells of connective tissue proper
• Contains accesory organs of epidermal origin - hair follicles, sweat glands,
• contains network of blood vessels and nerve fibers

Question 5

dermatitis

Answer 5

inflammation of the dermis that primarily involves papillary layer. Can be infection or chemical irritation Ex: poison ivy

Question 6

Fibers of the dermis

Answer 6

• Collagen fibers: Provide flexibilty. strong, resist stretching.
• Elastic fibers: Limit flexibility to aboid damage. Permit stretching and recoil.

Question 7

tretinoin (Retin-A)

Answer 7

Increases blood flow to the dermis and stimulates dermal repair. Rate of wrinkle formation decreases, existing wrinkles become smaller.

Question 8

cleavage (tension) lines

Answer 8

• A pattern that results from the parallel orientation of bundles of collagen and elastic fibers to resist forces applied to the skin.
• A cut parallel will heal with less scarring,

Question 9

cutaneous plexus

Answer 9

• the network of ateries in the hypodermis that supply the skin
• tributaries supple adipose tissue of subcutaenous layers and tissues of integument
• Branches supply hair follicles, sweat glands, etc. structures

Question 10

papillary plexus

Answer 10

When arteries reach the papillary layer, form another branched network to provide blood to the capillary loops along the epidermis-dermis boundary.

Question 11

venous plexus

Answer 11

• Blood travels from papillary plexus to capillaries that empty into the venous plexus deep to papillary plexus.
• Continues to larger venous plexus in the hypodermis

Question 12

decubitis ulcers

Answer 12

Result of problems with dermal circulation.

ulcer: Localized shedding of an epithelium

decubitis ulcers (bedsores): affect patients where circulation is restricted. Lying in bed compresses superficial blood vessels.