Integumentary System

Question 1

Integumentary system

Answer 1

-Consists of the skin including the sebaceous glands, sweat glands, hair, and nails
-serves a variety of functions associated with protection, secretion, and communication

Question 2

Protection

Answer 2

The integumentary system protects the body from pathogens including bacteria, viruses, and various chemicals

Question 3

Secretion

Answer 3

-Sebaceous glands secrete sebum (oil) that waterproofs the skin
- glands also serve as excretory organs and help rid the body of metabolic wastes

Question 4

[skin]
Communication

Answer 4

-Sensory receptors distributed throughout the skin send information to the brain regarding pain, touch, pressure, and temperature
-in addition to protection, secretion and communication the skin manufactures vitamin D and can absorb certain chemicals such as specific medications

Question 5

Layers of the skin (1/2)

Answer 5

-From the surface of the skin inward are the epidermis and dermis
-the subcutaneous layer lying below the dermis is also part of the integumentary system
-the epidermis is the most superficial layer of the skin
-the epidermidis consists entirely of epithelial cells and does not contain any blood vessels
-the deepest portion of the epidermis is the stratum basale, which is a single layer of cells that continually undergo division
-as more and more cells are produced, older cells are pushed toward the surface
-most epidermal cells are keratinized
-keratin is a waxy proteins that helps to waterproof the skin
-as the cells die, they are sloughed off

Question 6

Layers of the skin (2/2)

Answer 6

-the dermis lies directly beneath the epidermis
-the dermis consist mostly of connective tissue
-the dermis contains blood vessels, sensory receptors, hair follicles, sebaceous glands, and sweat glands
-the dermis also contains elastin and collagen fibers
-the subcutaneous layer, or hypodermis, is actually not a layer of the skin
-the subcutaneous layer consists of connective tissue, which binds the skin to the underlying muscles
-fat deposits in the subcutaneous layer help to cushion and insulate the body

Question 7

Question 8

[cell type, location, description]
Keratinocytes

Answer 8

-Location: epidermis
-Description:
-The most common type of cell in the epidermis
-arise from stem cells in the stratum basale
-they flatten and die as they move toward the surface of the skin
-produce keratin, a fibrous protein that hardens the cell and helps make the skin water resistant

Question 9

[cell type, location, description]
Melanocytes

Answer 9

-Location: epidermis
-Description: produces melanin, a pigment that gives skin its color and protects against UV radiation

Question 10

[cell type, location, description]
Langerhans cells

Answer 10

-Location: epidermis
-Description: antigen-presenting cells of the immune system (phagocytes)
-more common in stratum spinosum than other layers of epidermis

Question 11

[cell type, location, description]
Merkel cells

Answer 11

-Location: epidermis
-Description: cutaneous receptors, detect light touch
located in stratum basale

Question 12

[cell type, location, description]
Fibroblasts

Answer 12

-Location: dermis
-Description: secrete collagen, elastin, glycosaminoglycans, and other components of the extracellular matrix

Question 13

[cell type, location, description]
Adipocytes

Answer 13

-Location: dermis
-Description: fat cells

Question 14

[cell type, location, description]
Macrophages

Answer 14

-Location: dermis
-Description: phagocytic cells that engulf potential pathogens

Question 15

[cell type, location, description]
Mast cells

Answer 15

-Location: dermis
-Description: antigen-presenting cells that play a role in the inflammatory response (release histamine)

Question 16

Question 17

Temperature homeostasis

Answer 17

-Skin is involved in temperature homeostasis or thermoregulation through the activation of the sweat glands
-by thermal regulation, the body maintains a stable body temperature
-the temperature of the body is controlled by negative feedback system consisting of receptor, control center, and effector
-the receptors are sensory cells in the dermis of the skin
-the control center is the hypothalamus, which is located in the brain
-effectors include the sweat glands, blood vessels, and muscles (shivering)
-The evaporation of sweat across the surface of the skin cools the body to maintain its tolerance range
-vasodilation of the blood vessels near the surface of the skin also releases heat into the environment to lower body temperature
-shivering is associated with the muscular system

Question 18

Sebaceous glands

Answer 18

-Sebaceous glands and sweat glands are exocrine glands found in the skin
-exocrine glands secrete substances into ducts
-in this case, the secretions are through the ducts to the surface of the skin
-sebaceous glands are holocrine glands, which secrete sebum
-sebum is an oily mixture of lipids and proteins
-sebaceous glands are connected to hair follicles and secrete sebum through the hair pore
-sebum inhibits water loss from the skin and protects against bacterial and fungal infections

Question 19

Sweat glands

Answer 19

Either eccrine glands or aprocine glands

Question 20

[sweat glands]
Eccrine glands

Answer 20

-eccrine glands are not connected to hair follicles
-they are activated by elevated body temperature
-eccrine glands are located throughout the body and can be found on the forehead, neck, and back
-eccrine glands secrete a salty solution of electrolytes and water containing sodium chloride, potassium, bicarbonate, glucose, and antimicrobial peptides
-eccrine glands are activated as part of the body‘s thermoregulation

Question 21

[sweat glands]
Apocrine glands

Answer 21

-Secrete an oily solution containing fatty acids, triglycerides, and proteins
-apocrine glands are located in the armpits, groin, palms, and soles of the feet
-apocrine glands secrete this oily sweat when a person experiences stress or anxiety
-bacteria feed on apocrine sweat and expel aromatic fatty acids, producing body odor