The document discusses the integumentary system. It is divided into skin, hair, glands, and nails. The skin is the largest organ and consists of three layers - the epidermis, dermis, and hypodermis. The skin acts as a protective physical barrier from injury, UV light, and bacterial invasion through its layers. It also acts as a non-specific immunity barrier along with tears and saliva.

1. Mukhtar khalif mohamedMukhtar khalif mohamed

2. Integumentary SystemIntegumentary System
Chapter 5Chapter 5

3.  Objectives:Objectives:
1- Describe the functions of the1- Describe the functions of the
integumentary system.integumentary system.
2- Identify the major structures found in the2- Identify the major structures found in the
three layers of the skin.three layers of the skin.
3. Describe the anatomy and physiology of3. Describe the anatomy and physiology of
hair and nailshair and nails
4. Define some common4. Define some common
dermatopathological disorders.dermatopathological disorders.

4.  This system is divided into:This system is divided into:
1- skin1- skin
2- hair2- hair
3- glands3- glands
4- nails4- nails
5- nerve endings5- nerve endings
I)I) SkinSkin
Skin is an organ because it consists ofSkin is an organ because it consists of
different tissues that are joined to perform adifferent tissues that are joined to perform a
specific function.specific function.
Largest organ of the body in surface area andLargest organ of the body in surface area and
weight.weight.
DermatologyDermatology is the medical specialtyis the medical specialty
concerning the diagnosing and treatment ofconcerning the diagnosing and treatment of skinskin
disorders.disorders.

6. Anatomy (structure)Anatomy (structure)
EpidermisEpidermis (thinner outer layer of skin)(thinner outer layer of skin)
DermisDermis (thicker connective tissue layer)(thicker connective tissue layer)
HypodermisHypodermis (subcutaneous layer or Sub-Q)(subcutaneous layer or Sub-Q)
Muscle and boneMuscle and bone
Physiology (function)Physiology (function)
1- Protection1- Protection
- physical barrier that protects underlying tissues- physical barrier that protects underlying tissues
from injury, UV light and bacterial invasion.from injury, UV light and bacterial invasion.
- mechanical barrier is part- mechanical barrier is part non specificnon specific
immunityimmunity (skin, tears and saliva).(skin, tears and saliva).

7. Anatomy (structure)Anatomy (structure)
EpidermisEpidermis (thinner outer layer of skin)(thinner outer layer of skin)
DermisDermis (thicker connective tissue layer)(thicker connective tissue layer)
HypodermisHypodermis (subcutaneous layer or Sub-Q)(subcutaneous layer or Sub-Q)
Muscle and boneMuscle and bone
Physiology (function)Physiology (function)
1- Protection1- Protection
- physical barrier that protects underlying- physical barrier that protects underlying
tissues from injury, UV light and bacterialtissues from injury, UV light and bacterial
invasion.invasion.
- mechanical barrier is part- mechanical barrier is part non specificnon specific
immunityimmunity (skin, tears and saliva).(skin, tears and saliva).