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Outline chapter 5
Test back Corrections tonight after school,
tomorrow at 7:00 am
Outline p. 100-105 due tomorrow
Project: building day on Wednesday
Due on Friday
Tuesday: finish notes
Wednesday: build models
Thursday: Review page, some build time
Friday: notes, microscope if time
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Chapter 5: Integumentary System
Objectives List functions of skin Explain role of skin in temperature regulation
Describe layers of skin and characteristics
Explain factors that affect skin color
Describe accessory organs of skin
Functions
ProtectionTemperature Regulation
Vitamin DSensoryExcretion
Integumentary SystemConsists of skin and accessory organs
Skin is 2 regions: Dermis epidermis
A fatty layer lies deep (hypodermis)
Hair Follicles Skin Glands Nails
Skin is the body’s outer covering and its largest organ.
Epidermis
Dermis
HypodermisOr subcutaneous
Structure of Skin
Epidermis
Stratified Squamous Epithelium (tissue)
Keratinized: keratin is a tough protein
Keratinized: By the time cells reach surface, little more than keratin filled sacsDesquamification: shedding of outermost layer of a tissue
Epidermis
No direct blood supplyNutrients must diffuse into the epidermis
Four types of cellsKeratinocytes – deepest, produce keratin Melanocytes - make dark skin pigment melanin Merkel cells – associated with sensory nerve endings Langerhans cells – macrophage-like dendritic cells
Review
1. The functions of the skin include all of the following except:
a. Taking in nutrientsb. Preventing entry of microorganismsc. Retarding water lossd. Regulating body temperature
Review
1. Which layer of the Integumentary System is the foundation for the skin?
a. Epidermisb. Hypodermisc. Dermisd. Stratum Corneum
Review
1. Which of the following is NOT considered an accessory organ of the Integumentary System?
a. nailsb. hairc. arteriesd. glands
Review
1. Which of the following cell types is responsible for sensory in the epidermis?
a. Langerhansb. Keratinocytesc. Melanocytesd. Merkel
Epidermis: most superficial
Stratum Corneum: Many layers of dead cells keratin, Moisture lock
Stratum Lucidum:Stratum Granulosum:Statum Spinosum:Stratum Basale:
Stratum Corneum: Stratum Lucidum:
Protect from UV Thick layer Only in frequently used areas
Stratum Granulosum:Statum Spinosum:Stratum Basale:
Stratum Corneum: Stratum Lucidum:Stratum Granulosum:
Thin middle layer Layers of keratinocytes Initiate keratinization
Statum Spinosum:Stratum Basale:
Stratum Corneum: Stratum Lucidum:Stratum Granulosum:Statum Spinosum:
Cells interlock to support skin Resist tension Langerhans cells (found more here than other layers)
Stratum Basale:
Stratum Corneum: Stratum Lucidum:Stratum Granulosum:Statum Spinosum:Stratum Basale:
Single layer of cells Rest on basement membrane Cells divide continuously Youngest cells found here Melanocytes & Merkel cells here
Epithelium: layers (on left) and cell types (on right)