groups of tissues working together to perform a common function
2 DIFFERENT TYPES OF TISSUES:
4 DIFFERENT KINDS OF MEMBRANES IN THE BODY:
What is mucous and its function?
Mucous- lines passages that opens to the exterior of body. Ex: squamous, or columnar epithelium
Functions: traps particles; coats olfactory receptors; lubricate foods in mouth; protects lining of stomach & intestine from digestive juice.
What is serous & its functions?
Serous- lines closed cavities of the body. Ex: simple squamous epithelium
- Functions: secretes serous fluid for lubriation
What is synovial & its functions?
Synovial- lines joint cavities. Ex: connective tissues only
- Functions: secretes fluid=synovial fluid- reduces friction at moveable joints
- Also forms fluid filled sacs around joints=bursae-reduces friction of mucles, tendon and legaments moving
What is cutaneous & its functions?
- Cutaneous- is the integumentary systems also called the skin.
- The largest organ in our body.
- Covers outer layer and surface of the body.
Integumentary System (Skin)
- considered an organ or an organ system.
- body's largest organ.
General function of Integumentary system (Skin)
- Acts as a protective barrier
- Temperature homeostasis
- Excretion of metabolic wastes
- Sense of touch
- Synthesis of Vitamin D
Layers of Skin
- Avascular-no direct blood supply
- Stratified squamous epithelium
- Lower layer living cells; upper layer dead filled with keratin
- Subdivided into 5 identifiable layer
- Stratum Basale- lowermost layer of epidermis; single cell layer thick
- Stratum Corneum- thickest of all layers; thickness of epidermis; dead cells completed filled with keratin; water resistant; main protection against biological and chemical assult
- Thickest layer in skin.
- Strong, flexible, connective tissues
- Gives skin its strength and resilience
- Gel-like matrix
- Rich in nerves, receptor, blood vessels, lymph vessels
- Hair follicles and sweat glands
- 2 layers:
- papillary layer (upper)
- reticular layer (lower)
- Due to combination of 3 different pigments
- 1. melanin- yellow, orange, brown or black pigments; racial shades due mainly to kinds and amount of melanin pigments
- 2. carotene- in stratum corneum and hypodermis layer
- 3. hemoglobin- blood of skin capillaries
Skin colors and textures in diagnosis:
- Cyanosis= bluish cast--> poor oxygenation
- erythema= redness--> emotional, hypertension, inflammation
- Jaundice= yellowing--> liver disorder, bile pigments in blood.
Derivitives of Skin:
- Hair- heavily keratinixed; consist of shaft, root, follicle, papillae, arrector pili, oil glands, hair receptor; color of hair depends on kinds of and amount of melanin
- Nails- scale like modification of epidermis
- Skin glands- oil gland, sweat gland, mammary gland (milk) ceruminous gland (ear wax)
Skin Imblances and Aging
- Burn- too much sunlight or heat. 1st degree-surface layer of skin is shed; 2nd degree-deep injury, blisters form as fluid builds up; 3rd degree- full thickness of skin is destroyed, dehydration, susceptible to infections, extend of burn damage estimated by rule of 9's
- Skin cancer - caused by UV, xray or radiaiton
- Types of cancer: actinic keratosis; basal cell carcinoma; squamous cell carcinoma; maliganant melanoma