Lab 9 (Unit 3) Flashcards
What is the epidermis made of?
- stratified squamous epithelium
- avascular
- regenerates ever 35-45 days
- 4 or 5 cell layers
What are the layers of the epidermis from superficial to deep?
- stratum corneum
- stratum lucidum
- stratum granulosum
- stratum spinosum
- stratum basale
keratinization
- process by which cells contents are replaced with keratin
- these cells are dead but strong
Dermis
- underlies epidermis
- strong, flexible connective tissue
- highly vascularized
- innervated
- 2 layers: papillary and reticular
Papillary layer
- superficial
- areolar connective tissue
- provides nutrients to epidermis
- dermal papillae increase surface area for transport of materials into epidermis
Reticular layer
- deep
- mostly dense irregular
- network of collagen and elastic fibers provide stretch and strength
Hair
-comprised of keratinized cells
Hair follicle
- generates the cells forming hair
- located in dermis
Arrector pili muscle
- raises hair
- causes goosebumps
- located in the dermis
Mercorine sweat glands
- sweat in response to heat or stress
- opens onto surface of the skin
- 99% water and 1% salts/wastes
- acidic to help prevent bacteria growth
Apocrine sweat glands
- responsible for body odor
- open onto hair follicles
- produces lipids and proteins
- found in armpits and groin
Hypodermis
- supports skin
- made of areolar and adipose loose connective tissue
- allows movement of skin over muscle and bones
Breakdown of spinal nerves
- 8 cervical: named for vertebra directly below
- 12 thoracic
- 5 lumbar
- 5 sacral
- 1 coccygeal
- all other nerves are named for vertebrae directly above
Ventral roots
- motor axons only
- motor neuron cell bodies are in ventral horn
Dorsal roots
- sensory axons only
- sensory axon cell bodies are in dorsal root ganglion
Spinal nerves: rami
- spinal nerves travel through intervertebral foramen then splits into dorsal and ventral rami
- ventral rami: form plexuses
- dorsal rami: innervate small strip of back
Axillary nerve
- sensory: shoulder joint and skin on part of deltoid
- motor: teres minor and deltoid
Radial nerve
- sensory: skin over dorso-lateral arm, forearm, and hand
- motor: posterior compartment of arm and forearm
Musculocutaneous nerve
- sensory: skin sensation for lateral forearm
- motor: anterior part of arm
Median nerve
- sensory: skin of lateral palm and digits 1-3 and lateral side of 4
- motor: anterior compartment of forearm, intrinsic muscles
Ulnar nerve
- sensory: skin of medial hand, medial digit 4, all of 5
- motor: flexors and intrinsic hand muscles
Fermoral nerve
- sensory: skin of antero-medial thigh and skin of medial leg and foot
- motor: muscles of anterior thigh, thigh flexors and leg extensors
Obturator nerve
- sensory: skin of medial thigh
- motor: muscles of medial thigh, adductors
pudendal nerve
- sensory: skin of external genitalia
- motor: muscles of perineum, external and internal sphincter, external urethral sphincter