Download - chapter 6: integumentary system
![Page 1: chapter 6: integumentary system](https://reader036.vdocuments.net/reader036/viewer/2022062404/554b43dfb4c905b5378b4e25/html5/thumbnails/1.jpg)
Chapter 6
Integumentary System
![Page 2: chapter 6: integumentary system](https://reader036.vdocuments.net/reader036/viewer/2022062404/554b43dfb4c905b5378b4e25/html5/thumbnails/2.jpg)
OrganAn organ consists of two or more types of tissues grouped together that perform a specialized task.
Integumentary System Includes the skin plus accessory structuresSkin is the largest organ in our body
![Page 3: chapter 6: integumentary system](https://reader036.vdocuments.net/reader036/viewer/2022062404/554b43dfb4c905b5378b4e25/html5/thumbnails/3.jpg)
Functions of skin include1. Forms protective coating
2. Retards water loss
3. Vitamin D synthesis
4. Temperature control
5. Houses sensory receptors
![Page 4: chapter 6: integumentary system](https://reader036.vdocuments.net/reader036/viewer/2022062404/554b43dfb4c905b5378b4e25/html5/thumbnails/4.jpg)
The skin is composed of 2 layers 1. Epidermis
2. Dermis
The subcutaneous layer (hypodermis) lies beneath the skin, but is not considered part of the skin.
![Page 5: chapter 6: integumentary system](https://reader036.vdocuments.net/reader036/viewer/2022062404/554b43dfb4c905b5378b4e25/html5/thumbnails/5.jpg)
EpidermisOutermost layer of skin
Stratified squamous epithelium
Outermost layers are keratinized
No direct blood supply – Receives nutrients by diffusion
![Page 6: chapter 6: integumentary system](https://reader036.vdocuments.net/reader036/viewer/2022062404/554b43dfb4c905b5378b4e25/html5/thumbnails/6.jpg)
There are five (5) layers of the epidermis: Stratum corneum Stratum lucidum Stratum granulosum Stratum spinosum Stratum basale
![Page 7: chapter 6: integumentary system](https://reader036.vdocuments.net/reader036/viewer/2022062404/554b43dfb4c905b5378b4e25/html5/thumbnails/7.jpg)
Stratum corneumIs the outermost layer of epidermisComposed of tightly packed dead cellsCells are keratinized
Keratin = water insoluble protein
Stratum basaleDeepest layer of epidermisCells are nourished by dermal blood vesselsSite of cell growth and divisionStratum Basal contains Melanocytes
Layers of the epidermis
![Page 8: chapter 6: integumentary system](https://reader036.vdocuments.net/reader036/viewer/2022062404/554b43dfb4c905b5378b4e25/html5/thumbnails/8.jpg)
MelanocytesSecrete melanin – pigment
Number of melanocytes is similar in all people
Darker skin from darker and larger melanin granules
Albinism – mutation resulting in no melanin production
![Page 9: chapter 6: integumentary system](https://reader036.vdocuments.net/reader036/viewer/2022062404/554b43dfb4c905b5378b4e25/html5/thumbnails/9.jpg)
Figure 6.4a A melanocyte with melanin granules
Figure 6.5 The red eyes and pale skin reflect the lack of melanin in albinism.
![Page 10: chapter 6: integumentary system](https://reader036.vdocuments.net/reader036/viewer/2022062404/554b43dfb4c905b5378b4e25/html5/thumbnails/10.jpg)
DermisDeeper layer of skinComposed of dense irregular connective tissueContains dermal papillaeBlood vessels and nervesHair folliclesSweat glands and Sebaceous glands
![Page 11: chapter 6: integumentary system](https://reader036.vdocuments.net/reader036/viewer/2022062404/554b43dfb4c905b5378b4e25/html5/thumbnails/11.jpg)
Figure 6.2 Section of skin
![Page 12: chapter 6: integumentary system](https://reader036.vdocuments.net/reader036/viewer/2022062404/554b43dfb4c905b5378b4e25/html5/thumbnails/12.jpg)
Sweat Glands - secrete sweat onto surface of the skinEccrine glands – respond to elevated temperaturesApocrine glands - anxiety, sexual arousal, and pain
Sebacous glandsAssociated with hair folliclesSecretes Sebum – oilKeeps hair and skin soft and waterproof
![Page 13: chapter 6: integumentary system](https://reader036.vdocuments.net/reader036/viewer/2022062404/554b43dfb4c905b5378b4e25/html5/thumbnails/13.jpg)
Subcutaneous layer (often called hypodermis)Subcutaneous layer – not part of skin
Comoposed of adipose tissue, areolar tissue, and blood vessels
The subcutaneous layer binds skin to underlying organs
Adipose insulates the body
![Page 14: chapter 6: integumentary system](https://reader036.vdocuments.net/reader036/viewer/2022062404/554b43dfb4c905b5378b4e25/html5/thumbnails/14.jpg)
End of Chapter 6