BIOLOGY 2401 ANATOMY

1
BIOLOGY 2401ANATOMY PHYSIOLOGYPART ICHAPTER 5

• THE INTEGUMENTARY SYSTEM

2
THE SKIN

• The skin (cutaneous membrane) is made up of two
  distinct tissues
  
• The epidermis
• A stratified squamous epithelial layer
• Avascular
• The dermis
• A dense irregular connective tissue

3
EPIDERMIS - 4 Cell Types

• Keratinocytes
• Produce keratin
• Arise from the basal layer by continuous mitosis
• Melanocytes
• Produce and store melanin
• Merkel cells
• Touch receptors
• Langerhans cells
• Macrophages that aid in skin defense

4
(No Transcript)
5
Thick skin
6
Thin skin
7
Thin skin, melanin
1000x
8
Thin skin, hairy
100x
9
DERMIS

• Contains cells such as fibroblasts, macrophages,
  mast cells, etc.
  
• This tissue is thickly supplied with blood, and
  nerve fibers for the senses.
  
• There are two layers to the dermis
• Papillary layer
• Thin but rich in blood vessels and sensory cells
• Reticular layer
• Accounts for 80 of the dermal thickness
• Most appendages to the skin are found in this
  layer

10
SKIN COLOR

• The color of skin depends on 3 types of
  pigments
  
• Melanin produced in the skin
• Melanin can have several colors from yellow to
  black
  
• Sun exposure speeds up the production and
  accumulation of melanin.
  
• Carotene
• Hemoglobin

11
APPENDAGES OF THE SKIN

• Sweat glands
• Eccrine sweat glands found throughout body
• Apocrine sweat glands found in the axilla and
  anogenital regions
  
• Ceruminous glands - earwax
• Mammary glands
• Sebaceous glands oil glands
• Glands that release oil for protection of skin
  and hair.
  
• Pimples and blackheads are due to infection of
  sebaceous glands by bacteria
  
• Nails
• Scale like extensions from epithelial cells
• Contain hard keratin

12
(No Transcript)
13
FUNCTIONS OF THE INTEGUMENTARY SYSTEM

• Protection
• Body temperature regulation
• Cutaneous sensation
• Metabolic functions vitamin D production
• Blood reservoir

14
DISORDERS OF THE SKIN

• Infections
• Ulcers due to infection or poor blood supply
• Skin cancer
• Basal cell carcinoma basal layer cells
• Squamous cell carcinoma higher layer cells
• Melanoma melanocytes most metastatic

15
Burns

• 1st degree only epidermis
• 2nd degree epidermis upper dermis
• 3rd degree entire thickness of skin
• Dehydration is most immediate cause of death
• Infection is the next major concern

16
Rule of Nines

• Estimates the severity of burns
• Burns considered critical if
• Over 25 of the body has second-degree burns
• Over 10 of the body has third-degree burns
• There are third-degree burns on face, hands, or
  feet
  

17
Rule of nines

• Body is divided into 11 major areas
• Head (1)
• Arms (2)
• Trunk(4)
• Legs (4)
• Each major body area is a 9 (9)
• Or a multiple of 9
• Example Burned right leg (18) burned right
  arm (9) 27
  
• We would say person has burns on 30 of body.

18
Practice Questions

•  

19

• Sebaceous glands are located in all of the
  following areas except the 
  
• palmar region. 
• brachial region. 
• axillary region. 
• abdominal region. 
• scalp.

20

• The dermis is primarily composed of which tissue
  type? 
  
• Reticular connective tissue 
• Dense regular connective tissue 
• Stratified squamous epithelial tissue 
• Areolar connective tissue 
• Dense irregular connective tissue

21

• The epidermis is composed of which of the
  following tissues? 
  
• Areolar connective tissue 
• Adipose connective tissue 
• Stratified columnar epithelial tissue 
• Dense irregular connective tissue 
• Keratinized stratified squamous epithelial tissue

22

• What is the primary biological function of
  melanin?  (hint not color)
  
• Uptake of calcium from the diet 
• Produces vitamin D 
• Provides protection against the sun's UV rays 
• Determines skin color 
• (This is a consequence but not the primary
  function)
  
• E. Produces sebum

23

• Which of the following human integumentary system
  glands is believed to be analogous to the sexual
  scent glands of an animal? 
  
• Sebaceous gland 
• Ceruminous gland 
• Apocrine sudoriferous gland 
• Eccrine sudoriferous gland 
• Mammary gland

24

• Which of the following is most important in
  determining skin coloration? 
  
• Collagen 
• Keratin 
• Hemoglobin 
• Melanin 
• Carotene

25

• Which of the following is the most immediate
  threat to life from a serious burn? 
  
• Tissue destruction 
• Nerve damage 
• Blistering 
• Infection 
• Loss of body fluids

26

• Which of the following is the next threat to life
  from a serious burn? 
  
• Tissue destruction 
• Nerve damage 
• Blistering 
• Infection 
• Loss of body fluids

27

• Which of the following layers of the skin relies
  on capillaries in the underlying connective
  tissue in the dermis for its nutrients? 
  
• Epidermis  
• Hypodermis    
• Dermis

28

• Because of the great thickness of the epidermis,
  it is very vascular.  True False

29

• The body produces carotene when exposed to
  sunlight.  True False

30

• The melanocytes are the most abundant cells in
  the epidermis.  True False

31

• The skin functions in synthesizing vitamin
  D.  True False

32

• The superficial region of the skin is called the
  epidermis.  True False

33

• Blood vessels in the dermis constrict when the
  external environment is cold, minimizing heat
  loss from the skin.  True False