Integumentary System

Question 1

The integumentary system is composed of:

Answer 1

• Skin (main component)
• Hair
• Nails
• Sweat glands
• Sebaceous glands
• Mammary glands

Question 2

What are sweat glands, sebaceous glands, and mammary glands examples of?

Answer 2

Exocrine glands- secretion through ducts

Question 3

What are the functions of the integumentary system?

Answer 3

• Protection
• Thermoregulation
• Synthesis of hormones
• Sensation

Question 4

What are the two subcomponents of the cutaneous membrane (skin)?

Answer 4

Epidermis and dermis

Question 5

Epidermis

Answer 5

• Protects dermis from trauma, chemicals
• Controls skin permeability, and prevents water loss
• Prevents entry of pathogens
• Synthesizes vitamin D3
• Sensory receptors detect touch, pressure, pain, and temperature

Question 6

What are the two layers of the dermis, which is superficial and which is deeper?

Answer 6

Papillary layer and Reticular layer.
The Papillary layer is superficial.

Question 7

Papillary layer of the dermis

Answer 7

Nourishes and supports epidermis

Question 8

Reticular layer of the dermis

Answer 8

• Restricts spread of pathogens penetrating epidermis
• Stores lipids
• Attaches skin to deeper tissues
• Sensory receptors detect touch, pressure, pain, vibration, and temperature
• Blood vessels assist in thermoregulation

Question 9

What are the accessory structures of the integumentary system?

Answer 9

Hair follicles
Exocrine glands
Nails

Question 10

Function of hair follices

Answer 10

• Produce hairs that protect skull
• Produce hairs that provide delicate touch sensations on general body surface

Question 11

Function of Exocrine glands

Answer 11

• Assist in thermoregulation
• Excrete wastes
• Lubricate epidermis

Question 12

Function of Nails

Answer 12

• Protect and support tips of fingers and toes

Question 13

What attaches to the hair follicle (muscle)?

Answer 13

Arrector pilli muscle (goosebumps)

Question 14

What are the functions of the integumentary system?

Answer 14

Physical protection- containment of internal structures
Regulation of body temperature
Excretion of products- sweat, oil, etc
Synthesis of products- sunlight exposure key for Vitamin D synthesis
Sensation- awareness of environment
Immune defense- protection from pathogens

Question 15

What are the four cell types found in the epidermis?

Answer 15

Keratinocytes
Melanocytes
Merkel cells
Langerhans cells

Question 16

Function of keratinocytes

Answer 16

Keratin is a major structural protein of integumentray structures; it attracts water

Question 17

Function of melanocytes

Answer 17

Produce pigments; melanin protects us from UV rays

Question 18

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

Answer 18

Stratum corneum
Stratum lucidum
Stratum granulosum
Stratum spinosum
Stratum basale

Question 19

Stratum Corneum

Answer 19

• Contains multiple layers of flattened, dead, interlocking keratinocytes
• Typically is relatively dry
• Water resistant but not waterproof
• permits slow water loss by insensible perspiration

Question 20

Stratum Lucidum

Answer 20

Appears as a glassy layer in thick skin only

Question 21

Stratum Granulosum

Answer 21

• Keratinocytes produce keratohyalin and keratin
• Keratin fibers develop as cells become thinner and flatter
• Gradually, the cell membranes thicken, the organelles disintegrate, and the cells die

Question 22

Stratum Spinosum

Answer 22

• Keratinocytes are bound together by maculae adherens attached to tonofibrils of the cytoskeleton
• Some keratinocytes divide in this layer
• Langerhans cells and melanocytes are often present

Question 23

Stratum Basale

Answer 23

• Is the deepest, basal layer
• Attachment to basal lamina
• Contains epidermal basal (stem) cells, melanocytes, and Merkel cells

Question 24

What is below the Stratum basale?

Answer 24

Dermis

Question 25

Where is thick skin found?

Answer 25

Palms and soles of feet- friction higher in these areas so thicker skin is needed. Made of five layers of cells (including stratum lucidum)

Question 26

Where is thin skin found?

Answer 26

Rest of the body besides palms and soles of feet. Made of four layers of cells. because the stratum lucidum is typically absent

Question 27

What structure does the stratum basale form?

Answer 27

Dermal ridges. These ridges (dermal papillae) extend into the dermis, creating the ridges we call fingerprints. The dermal ridges are part of the epidermis.

Question 28

What are the unencapsulated tactile receptors?

Answer 28

Free nerve endings Root hair plexus Tactile disc

Question 29

Free nerve endings

Answer 29

A type of unencapsulated tactile receptor. Common in the dermis. Sensitive to pain, heat, cold.

Question 30

Root hair plexus

Answer 30

A type of unencapsulated tactile receptor. Associated with hair follicles. Monitors distortions and movements of hairs on the body surface.

Question 31

Tactile discs

Answer 31

A type of unencapsulated tactile receptor. Free nerve endings synapse with Merkel cells in the stratum basale of the epidermis. Sensitive to light contact with skin.

Question 32

What are the encapsulated tactile receptors?

Answer 32

Tactile corpuscle Bulbous corpuscle Lamellar corpuscle

Question 33

Tactile corpuscle

Answer 33

A type of encapsulated tactile receptor. Common on eyelids, lips, fingertips, nipples, and external genitalia Sensitive to initial contact and low-frequency fibration

Question 34

Bulbous corpuscle

Answer 34

A type of encapsulated tactile receptor Associated with collagen in the dermis Sensitive to stretching and distortion of the dermis

Question 35

Lamellar corpuscle

Answer 35

A type of encapsulated tactile receptor Consists of concentric cellular layers Sensitive to deep pressure and high-frequency vibrations

Question 36

Types of Skin Cancer

Answer 36

Basal cell carcinoma- common Squamous cell carcinoma Melanoma- more serious and can spread to other areas

Question 37

Jaundice

Answer 37

A condition where bilirubin is not expelled from the body as it should be. Bilirubin is formed from the breakdown of hemoglobin when RBCs are recycled. Liver and gallbladder disorders cause jaundice. You would see yellowing of the skin and the white parts of the eye.

Question 38

Tension Lines/Cleavage Lines

Answer 38

- Collagen and elastic fibers have a tendency to organize themselves in a aparallel pattern Ib certain areas of the body, there is a pattern of cleavage lines due to stress or a specific type of movement To reduce scar formation (extensive damage to the fibers), surgeons try to cut parallel to the lines of cleavage

Question 39

Aging and the Integumentary System

Answer 39

- Epidermis becomes thinner - Vitamin D3 production decreases - Melanocyte activity declines - Glandular activity decreases - Blood supply to the dermis decreases - Hair follicles stop functioning - Dermis and its elastic fiber network become thinner - Skin repairs proceed more slowly

Question 40

The Subcutaneous Layer

Answer 40

- Important in stabilizing the position of the skin in relation to underlying tissues, while still permitting independent movement - Consists of loose connective tissue with abundant adipocytes