Lab 5: Integument A. Histology   Slide #19 (Scalp) Locate: epidermis --- stratum basale --- stratum spinosum --- stratum granulosum (may be absent) --- stratum corneum --- hair --- hair follicle --- external root sheath --- hair bulb --- matrix ---hair papilla  --- dermis --- arrector pili muscle --- sebaceous (oil) glands --- sudoriferous (sweat) glands.   Slide #20 (Thick skin) Locate five layers of epidermis including --- stratum basale --- stratum spinosum --- stratum granulosum --- stratum corneum; two layers of dermis including: papillary layer --- reticular layer --- epidermal pegs --- dermal papilla --- suderiferous (sweat) glands.   Slide # 21, 22  (Pacinian and Meissner’s corpuscles) The corpuscles of touch (Meissner’s corpuscle) are found in the dermal papillae and look a bit like whirlwinds. Not every papilla has one. Lamellated (Pacinian) corpuscles are found lower in the dermis or in the subcutaneous tissue (hypodermis). Lamellated corpuscles look like onions. B. Models (There are two. Know both!) Simple Skin Model & Composite Skin Model  Videos: Simple Skin Model: Epidermis, Dermis, Hair Follicle, Glands & Sensory Structures Composite Skin Model: Introduction, Epidermis & Dermis, Hair Follicle, Glands, Sensory Structures Between the two different skin models identify: all 4 or 5 strata of the epidermis --- eccrine sweat (sudoriferous) gland --- apocrine sweat gland --- two subdivisions of the dermis (reticular and papillary) --- dermal papilla --- hair root --- hair shaft --- sebaceous (oil) gland ---  hair papilla --- hair follicle --- bulb of hair follicle --- hair medulla --- hair cortex --- hair cuticle --- internal root sheath --- external root sheath --- arrector pili muscle --- subcutaneous layer (hypodermis) --- adipose tissue --- corpuscle of touch (Meissner’s) --- lamellated corpuscle (Pacinian). Note: the largest model of the skin shows skin from three sections of the body.