Chapter 6: Integumentary System
Name _________________________________Date_____Per__
I. Introduction to Skin and its Tissues
A. Basic Structure and Functions of the Skin
1. What are the major functions of the skin in regards to?
 pathogens

water

body temperature

other (receptors, chemicals & wastes)
2. Label the two distinct regions of the skin on the image to the right.
3. The outer layer is called the _______________________and is composed of
4. The inner layer is called the __________________and is made up of
5. Compare the vascularity of the dermis and the epidermis. How does the layer that is avascular get nutrients?
6. What is the hypodermis (superficial fascia)? Is it part of the skin?
7. What are the functions of the hypodermis?
B. The Epidermis
1. The tissue that makes up the epidermis is classified as?
2. What is the function of keratinocytes?
3. Draw desmosomes between the keratinocytes. What is
the function of these structures?
4. Keratinocytes on the lowest part of the epidermis are
constantly undergoing what process?
5. Describe the process of how “living keratinocytes” at
the base of the epidermis eventually become “dead
keratinocytes” at the surface of the epidermis.
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6. What is a callus or a corn? Why and how do they form?
7. What is a melanocyte?
8. Shade in the melanocyte to the right. Describe its shape.
9. Describe how melanin gets transported from a melanocyte to a
keratinocyte. What is the name of this process?
10. How does melanin act as a natural sun block?
11. Describe the shape, location and function of the epidermal dendritic cells (also known as Langerhans cells).
12. Describe the shape, location and function of the tactile cells (also known as Merkel cells).
13. Where would you find thick skin?
14. Where would you find thin skin?
15. Label & describe the layers of the epidermis:
a.
Stratum Basale
b.
Stratum Spinosum
c.
Stratum Granulosum
d.
Stratum Lucidum
e.
Stratum Corneum
16. What mnemonic can help you remember the layers of the
epidermis?
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II. The dermis
1. Describe the structure of the dermis.
2. How is the dermis nourished?
3. The boundary between the dermis and epidermis is uneven because of what structures?
4. Define the following sense organs of the skin and label each in
the image.
 Lamellated (Pacinian) corpuscles:

Meissner’s corpuscles:

Free nerve endings:
5. What is a fingerprint and how is it made?
6. What causes cleavage or tension lines? Why are they of importance to surgeons?
7. Below are other structures that might be found on your skin. Describe each in detail.
 Flexure Lines:

Stretch Marks:

Blisters:
III. Appendages of the Skin
A. Sweat Glands
1. What are the two types of sweat glands?
2. Describe eccrine glands and draw one in the box
(be sure to include a pore in your drawing).
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3. Where are eccrine glands found?
4. What is the function of eccrine glands?
5. Describe the structure and function of sweat.
6. Why is the term Apocrine gland misleading?
7. Describe apocrine glands and draw one in the box.
8. Compare the ducts of eccrine glands to those of apocrine glands.
9. Why does sweat smell?
10. When do apocrine glands become active?
11. Compare and contrast ceremonious glands and apocrine glands.
B. Sebaceous Glands
1. Where are sebaceous glands found?
2. Sebaceous glands secrete sebum. What are the functions of Sebum?
C. Hair Follicles
1. What produces hair?
2. What is hair?
3. Compare the hair root and the hair papilla.
4. Draw a hair follicle in the box. Include the arrector pili muscle.
5. What is the function of the arrector pili muscle?
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D. Baldness and Hair Color
1. What causes baldness?
2. How is hair colored?
3. Describe how each of the following hair color is produced:
 Dark hair:

Blonde/Red hair:

White hair:

Grey hair:
E. Nails
1. What is the function of the nails?
2. Label each of the structures of a fingernail.
3. What is the lunula?
IV. Skin Color
1. What are the three pigments that contribute to skin color?
2. If the numbers of melanocytes is the same among ethnicities how do you explain the various shades of skin color?
3. What is a freckle or a mole?
4. Geographically darker skinned people tend to be found near the equator. Why is this?
5. Describe how melanin acts as a “UV shield”?
6. What causes the leathery appearance of sun damaged skin?
7. Describe how the following factors affect skin color and what might have caused this to occur.

Carotene:

Oxygenated blood:

Exercise:

Constricted blood vessels:

Jaundice:

Black and blue marks:
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V. Functions and Regulation of the Integumentary System
A. Functions of the Integumentary System
1. Our skin is the most vulnerable organ system. The skin has three different barriers used for
protection describe each.
 Chemical barriers (acid mantle):

Physical barrier:

Biological barrier (dendritic cells, macrophages and DNA):
B. Body temperature Regulation
1. How does our body produce heat? (Hint: think cellular)
2. Describe how and why vasodilation occurs.
a. Does the skin redden or become pale due to
vasodilation?
3. Describe how and why vasoconstriction occurs.
a. Does the skin redden or become pale due to
vasoconstriction?
4. How much sweat is released daily?
Less heat
lost
5. What is the function of vitamin D?
VI. Homeostatic Imbalances of the skin
A. Skin Cancer
1. What is cancer?
2. Compare a benign tumor and a malignant tumor?
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3. The most important risk factor that contributes to skin cancer is?
4. How can UV radiation lead to skin cancer?
5. What other factors (other than UV) can lead to skin cancer?
6. How does the “Fas” protein protect sun damaged skin?
7. There are three major forms of skin cancer; basal cell carcinoma, squamous cell carcinoma and
squamous cell carcinoma. Describe each type of cancer, causes and treatment:
 Basal cell carcinoma:

Squamous cell carcinoma:

Melanoma:
8. Which type of skin cancer is the most dangerous? Why?
9. Describe the ABCD rule for recognizing melanoma?
10. Fill in the blanks below.
B. Burns
1. What is a burn?
2. What can cause a burn?
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3. What is the immediate threat to life resulting from a burn?
4. What is the rule of nines?
5. Describe the following classifications of burns.

1st degree burns

2nd degree burns

3rd degree burns
6. What is an autograft?
7. What is a homograft?
8. What are other skin substitutes?
C. Development & Aging
1. People have approximately the same number of sweat glands. Describe how climate determines sweat
gland activity.
2. Skin changes as an individual ages. Describe how each of the following changes as a result of aging.
Circle the appropriate answer.
 Rate of epidermal cell replacement (increases or decreases)

Skin (thickens

The production of lubricating substances produced by skin to make young skin soft
(increases
or
or
thins)
decreases)

The subcutaneous layer/hypodermis (increases

Deceasing elasticity of the skin leads to(wrinkled skin

The incidence of skin cancer (increases
or
decreases) due to decreasing numbers of melanocytes.

The number of hair follicles (increases
or
decreases)

The delayed action genes for graying and male patterned baldness (inactivate
or
decreases)
or
fresh and vibrant skin)
or
become active)
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