Chapter 4: Integumentary System

Question 1

What is the integumentary system composed of?

Answer 1

• Skin
• Hair
• Nails
• Sweat Glands
• Oil Glands
• Mammary Glands

Question 2

What is the cutaneous membrane made of?

Answer 2

Epidermis (superficial epithelium)
and dermis

Question 3

What are the accessory structures of the integumentary system?

Answer 3

Hair follicles, exocrine glands, and nails

Question 4

What are the functions of the integumentary system?
Why do we have it?

Answer 4

1. Physical Protection (mechanical abrasion also known as rubbing)
2. Regulation of body temperature (thermal window)we dump heat out of the body through the skin
3. Excretion of Products
4. Synthesis(making) of products
5. Sensation
   6.Immune defense( found heavily in the skin)

Question 5

Know the components of the Integumentary System

Question 6

The Epidermis(top layer) has ———- skin and ————-skin?

Answer 6

Thick skin
-Found on palms and soles
-Made if five layers

Thin skin
-Found on the rest of the body
-Made of four layers of cells

Question 7

What are the 4 types of cells found in the epidermis?

Answer 7

1. Keratinocytes (most abundant)
   Made of Keratinized stratified squamous epithelium in this layer
2. Melanocytes
   Pigment cells located deep in the epidermis and they produce melanin which is the skin color
3. Merkel cells
   sensory cells that give us a fine touch
4. Langerhans cells which are wondering macrophages that protect us in case anything enters the skin (immune)

Question 8

What are the five sub layers of the epidermis from deepest to most superficial?

Answer 8

1. Stratum Basale (deepest layer)
2. Stratum Spinosum
3. Stratum Granulosum
4. Stratum Lucidum (only found in thick skin)
5. Stratum Corneum (most superficial)

Question 9

Layers of the epidermis (more detail)
List the layers of the epidermis and what is found in that layer?

Answer 9

1.Stratum basale
Location of melanocytes
Cells in this area are undergoing active reproduction (i.e. mitosis)
2. Stratum Spinosum
Keratinocytes are bound together by desmosomes
3. Stratum granulosum
Keratinocytes produce lots of keratin
5. Stratum Corneum (entirely dead)
Superficial layer 

Question 10

Study the pictures of the skin to know the layers and other names

Question 11

How are blisters formed?

Answer 11

There is areolar connective tissue underneath the dermis which is mostly filled with water. Bless is formed when the keratinized portion is peeled apart and the fluid fills up and courses a bubble and since the fluid cannot leak out of the skin it just stays there

Question 12

What gives us our skin color?

Answer 12

Melanin(90%)
and carotene(10%)

Question 13

What is cyanosis?

Answer 13

It is when there’s enough blood flow but not enough oxygen in the blood and due to that the areas affected will look purple or blue

Question 14

What is the purpose of melanin?

Answer 14

It is produced and stored in melanocytes. It protects the skin against UV radiation (it is natures sunblock)

Question 15

What does carotene convert to?

Answer 15

It can convert to vitamin A, which is needed for synthesis of visual pigments in the photo receptors of the eyes

Question 16

What happens with repeated exposure to UV light?

Answer 16

1. It can result in long-term epidermal and dermal damage
2. It can result in epidermal skin cancer
3. It can result in premature wrinkling

Question 17

Vitamin D formation

Answer 17

1. We need some UV radiation because the body uses it to create vitamin D
2. UV light converts a cholesterol related precursor
3. Then it converts to vitamin D1 which undergoes changes in the liver and kidneys then vitamin D1 converts to the active form of vitamin D (calcitriol )

Question 18

What are the two layers of the dermis?
Identify it on the structure of the dermis figure

Answer 18

1. Papillary layer
   -Superficial layer
2. Reticular layer
   -Deep dermis

Question 19

Papillary layer (details)
What does it consist of:

Answer 19

1.Areolar connective tissue
2.Dermal Papillae
3.Capillaries- Capillaries are delicate blood vessels that exist throughout your body. They transport blood, nutrients and oxygen to cells in your organs and body systems
4.Nerve axons

Question 20

Reticular layer (details)
Consist of:

Answer 20

1.Dense irregular connective tissue
2.Hair follicles
3.Sweat glands
4.Sebaceous glands( sweat glands)

Question 21

Wrinkles

Answer 21

Collagen fibers provide tensile strength and elastic fibers allow the skin to stretch and recoil but when they cannot do that anymore we have wrinkles.

Wrinkles are due to age, change in hormone levels, UV light

Question 22

Stretch marks

Answer 22

Extensive stretch in during pregnancy or excessive weight gain can cause reticular fibers to break. The skin does not recoil so the skin wrinkles and creases resulting in stretch marks

Question 23

What are lines of cleavage?

Answer 23

Lines of cleavage is the areas where the dermis and all its collagen fibers arrange themselves in the parallel pattern and create lines below the skin

It also allows the skin to move in various ways

Question 24

How do we get goosebumps?

Answer 24

When we are cold the arrector pili muscle contracts and pores on the bottom of the hair follicle which causes the top of the hair to stand straight outside the body which pushes the skin to have the bump we know as goosebumps