Extra Terms

Question 1

Dermis

Answer 1

the deeper, thicker connective tissue. Vascular (contains blood vessels) Middle layer of skin.
made of collagen and elastic fibers. contains nerve fibers for sense. thermoregulation. oil and sweat glands.

Question 2

Hypodermis (subcutaneous tissue)

Answer 2

this layer consists of areolar and adipose tissue. serves as storage depot for fat and contains large blood vessels that supply the skin. also contains nerve endings call lamellated corpuscles that are sensititve to pressure.

Question 3

Meissner Corpuscles

Answer 3

(corpuscles of touch) nerve endings that are sensitive to touch. located in the dermal papillae of hairless skin.

Question 3

Pacinian Corpuscles

Answer 3

sensory receptors that detect vibrations, pressure and mechanical deformation. most common in hands and feet. built around nerve endings and surrounded by connective tissue. found between dermis and subcutaneous tissue.

Question 4

Free Nerve Endings

Answer 4

dendrites that lack any apparent structural specialization. Different free nerve endings initiate signals that give rise to sensations of warmth, coolness, pain, tickling, and itching.

Question 5

Melanosome

Answer 5

organelles that produce, store, and transport melanin. found in melanocytes. they protect against UV radiation.

Question 6

Papillary Region

Answer 6

Top layer of the dermis. makes up about 1/5 of the thickness of the total layer. contains thin collagen and fine elastic fibers. its surface area is greatly increased by dermal papillae, (small, nipple shaped projections that project into the undersurface of the epidermis. contain blood vessels, meissner corpuscles, and free nerve endings.)

Question 7

Reticular Region

Answer 7

attached to the subcutaneous layer, contains bundles of thick collagen fibers, scattered fibroblasts, and various wandering cells (such as macrophages) consists of dense irregular connective tissue. spaces between fibers contain some adipose cells, hair follicles, nerves, sebaceous glands, and sudoriferous glands.

Question 8

Thermoregulation

Answer 8

homeostatic regulation of body temperature. the skin does this in 2 ways: 1. by liberating sweat at its surface and by adjusting the flow of blood in the dermis. evaporation of sweat helps to lower body temperature. blood vessels contract (hot temps) 2. production of sweat from eccrine glands is decreased which helps conserve heat, blood vessels constrict limiting heat loss. (cold temps)

Question 9

Inflammation

Answer 9

a vascular and cellular response that helps eliminate microbes, foreign material, and dying tissue in preparation for repair. reaction to an injury or infection.

Question 10

Fibrosis

Answer 10

thickening and scarring of tissue. characterized by excessive buildup of fibrous connective tissue in the extracellular matrix. result of damage.

Question 11

Epidermis

Answer 11

superficial, thinner portion of the skin. protects against pathogens, produces new cells to replace old ones that shed naturally. contains melanin. houses langerhans cells.