Skin (layers, vascularization and nervous receptors)

1.      Match the following

__3__(a) deep region of the dermis composed primarily of dense irregular connective tissue

__4__(b) composed of keratinized stratified squamous epithelial tissue

__1__(c) not considered part of the skin, it contains areolar and adipose tissues and blood vessels; attaches skin to underlying tissues and organs

__2__(d) superficial region of the dermis; composed of areolar connective tissue

(1) subcutaneous layer (hypodermis)

(2) papillary region

(3) reticular region

(4) epidermis

2.      Match the following

__3__(a) produce the protein that helps protect the skin and underlying tissues from light, heat, microbes, and many chemicals

__5__ (b) produce a pigment that contributes to skin color and absorbs ultraviolet light

__4__ (c) cells that arise from red bone marrow, migrate to the epidermis, and participate in immune responses

__1__ (d) cells thought to function in the sensation of touch

___6_ (e) located in the dermis, they function in the sensations of warmth, coolness, pain, itching, and tickling

__7__ (f) smooth muscles associated with the hair follicles; when contracted, they pull the hair shafts perpendicular to the skin’s surface

_2___ (g) an abnormal thickening of the epidermis

__8__ (h) release a lipid-rich secretion that functions as a water-repellent sealant in the stratum granulosum

__9__ (i) pressure-sensitive cells found mostly in the subcutaneous layer

__10__ (j) a fatty substance that covers and protects the skin of the fetus from the constant exposure to amniotic fluid

__11__ (k) associated with hair follicles, these secrete an oily substance that helps prevent hair from becoming brittle, prevents evaporation of water from the

skin’s surface, and inhibits the growth of certain bacteria

(1) Merkel cells

(2) Callus

(3) Keratinocytes

(4) Langerhans cells

(5) Melanocytes

(6) Free nerve endings

(7) Sebaceous glands

(8) Lamellar granules

(9) Pacinian (lamellated) corpuscles

(10) Vernix caseosa

(11) Arrector pili

3.      What of the following layers of the skin is avascular

a)      Epidermis

b)     Dermis

c)      Ultradermis

d)     Adermis

4.      Avascular means

a)      Very rich in blood vessels

b)     Has few blood vessels

c)      Has no blood vessels

d)     Is very vascularized