chapter 4: integumentary system. entry task1/7 brainstorm and record 3 possible functions of the...
Post on 18-Dec-2015
222 views
TRANSCRIPT
Chapter 4: Integumentary System
Entry Task 1/7
Brainstorm AND record 3 possible functions of the integumentary (skin) system…
Wednesday 1/7
Mini-Quiz: Body Tissues
Begin CH 4: Skin & Body Membranes– Worksheet: Skin Structure
Take notes from PowerPoint– Integumentary System
Function Melanin p.108-114
Skin & Body Membranes
Epithelial tissue membrane (3 types)– Cutaneous
Stratified squamous on a layer of dense fibrous connective tissue
– MucousStratified squamous on simple
columnar– Serous
Simple squamous on areolar tissue
A Closer Look at the Serosa…
Parietal layer– lines ventral cavity, folds on itself to form visceral
layer
Visceral layer– covers outside of organs in cavity– Serous fluid fills the pocket
The Serosa
Skin & Body Membranes, cont…
Connective tissue membranes– Synovial
Soft areolar connective tissue
NO epithelial cells
Functions of I.S.
Protects from:– Mechanical, chemical, bacterial, UV, thermal, &
dessication
Heat loss/retention Excretion of urea/uric acid Makes Vitamin D Tells us about external environment
Structure
Epidermis– Stratified squamous
Dermis– Dense fibrous conn. tissue
Hypodermis– Adipose tissue
Firmly connected together!
Skin Structure
Epidermis
5 layers called “strata” (deep to superficial)– stratum basale – stratum spinosum– stratum granulosum – stratum lucidum– stratum corneum
Avascular—no blood supply Keratinocytes—produce keratin
Epidermis of Thick Skin
A Closer Look at the Strata…
Stratum basale– deepest layer– receives nutrients– constantly dividing
Stratum spinosum Stratum granulosum
– Cells become flatter, full of keratin Stratum lucidum
– Cells beginning to die, extra thick, hairless skin Stratum corneum
– DEAD!!!– 20-30 cell layers thick
Fun Facts
Every 25-45 days, you have a completely NEW epidermis!
Everything you see when you look at someone else is DEAD! Gross!
Melanin
Melanin is a pigment– yellow to brown to black– Melanocytes make the pigment
Freckles/moles – Melanin is concentrated in 1 area
Dermis
Your dermis is your “hide”– Strong, stretchy envelope– Dense fibrous conn. tissue
Collagen Elastic fibers
– 2 Regions: Papillary layer—upper dermis
– House pain receptors/free nerve endings & touch receptors (Meissner’s corpuscles)
Reticular layer—deepest skin layer– Pressure receptors (Pacinian corpuscles)
Dermis, continued…
Blood Vessels—maintain homeostasis Rich nerve supply
Entry Task 1/8
1. Explain the function of the stratum basale of the epidermal layer.
2. Why do we get wrinkled, saggy skin as we age? Be sure to identify the layer of skin involved in your answer.
3. What part of skin do you think pain receptors are found in? Touch receptors?
Tuesday 3/25
Explore the function of cutaneous receptors through a series of lab activities!
Review Entry Task Complete Cutaneous Receptors lab activity!
HW: Read p. 116-124
Wednesday 3/26
Finish “Cutaneous Receptors” Activity
Activity: Make a Sweat Map!
PowerPoint covering p.116-124– Take notes!!!
Skin Color
3 Pigments– Melanin– Carotene– Oxygen-rich hemoglobin
Alterations in skin color– redness/erythema– pallor/blanching– jaundice– bruises
Appendages of the Skin
Includes:– cutaneous glands, hair, hair follicles, and nails
Exocrine glands—release secretions through ducts– 2 Types
Sebaceous glands (oil) Sudoriferous glands (sweat)
Sebaceous Glands (Oil)
All over skin (not on palms/feet) Empties into hair follicles Secretes sebum—oil & fragmented cells
– Keeps skin soft– Has chemicals that kill bacteria– Clogged duct = whitehead
Sudoriferous Glands (sweat)
2.5 million/person 2 Types: Eccrine & Apocrine
Eccrine– More common, produces sweat– Heat regulation– 7L sweat on a hot day!
Sudoriferous Glands, cont…
Apocrine– Mainly in axillary & genital area– Larger than eccrine glands– Secretes fatty acid/protein along with other
components– Bacteria have a hay day!!!
Hair & Hair Follicles
Components:– Follicle: produces hair– Shaft: part of hair exposed to environment– Root: part of hair enclosed in the follicle– Medulla: central core– Cortex: area between medulla & cuticle– Cuticle: heavily keratinized; shingles– Arrector pili: smooth muscle, connects follicle to
tissue– Matrix: growth zone– Hair bulb: contain melanocytes
Nails
Components:– Free edge– Body– Root: embedded in skin– Nail folds: sides of nails, connected to skin– Cuticle: thick proximal nail fold– Lanula: crescent– Nail bed: extends beneath the nail– Nail matrix: thick part of nail bed; growth
Homeostatic Imbalances
Over 1000 ailments of the skin!– Mostly allergies, fungus, burns, & cancer
Athlete’s foot—fungus Boils/carbuncles—inflamed oil glands Cold sores—herpes virus Contact dermatitis—chemical contact Impetigo—bacterial infection Psoriasis—autoimmune disorder
Burns
Def: Tissue damage/cell death caused by intense heat
Skin = thick as a paper towel Almost all body systems suffer when skin is
burned
2 life threatening problems: fluid loss & kidney shutdown/circulatory shock
Burns, cont…
Rule of Nines:– Body divided into 11 areas, each covering 9%
surface area– Helps determine volume of fluid lost
Infection is leading cause of death Burns are sterile 24 hours after
– Then pathogens invade
Burn Classification
1° Burn– Epidermis damaged– Red, swollen– Lasts 2-3 days– EX: sunburn
Burn Classification
2° Burn– Epidermis & Upper
Dermis damaged– Red, painful blisters– Regrowth can occur– No permanent
scarring if taken care of
Burn Classification
3° Burn– Entire thickness of
skin destroyed– Blanched/Black– No pain—nerves
destroyed– Regeneration not
possible– Skin grafting
Burn Classification
CRITICAL burns meet this criteria:
– 25+% of the body has 2° burns– 10% has 3° burns– 3° burns on the face, hands, and/or feet
Skin Cancer
Most common of all cancers 1 in 5 people will have skin cancer in their
lifetime
3 Types– Basal cell carcinoma– Squamous cell carcinoma– Malignant melanoma
Basal Cell Carcinoma
Least malignant, most common
No keratin/boundary formed by stratum basale
Invades dermis/hypodermis
On face, shiny, slow-growing
Full cure @ 99% in most cases
Squamous Cell Carcinoma
Stratum spinosum Scaly, reddened papule Shallow ulcer, raised
border Scalp, ears, hands, lips Fast growing If caught early full
recovery can be made
Malignant Melanoma
Cancer of melanocytes 5+% cases are
melanoma Appears
spontaneously, develops from pigmented moles
brown to black patches 50% survival rate
ABCD Rule
Asymmetry– 2 sides of mole/spot don’t match
Border irregularity– Borders not smooth, have indents
Color– Different colors, range from black/brown/tan,
blues/reds
Diameter– 6+ mm
Thursday 3/27
Finish PowerPoint Notes Begin Review assignment
– P.127 MC: #1-2, 4, 6-7; SA: #1-4, 6-11, 13;
At the Clinic: #1-4
Identify different types of burns and skin cancers
Friday 3/28
Correct Review
Play Flyswatter Review game
Test over all of CH 4 on Monday after break!
Have a Great Spring Break!