Integumentary System

Question 1

What organ system consists of the skin, hair, nails, and exocrine glands?

Answer 1

Integumentary system

Question 2

What is the function of the exocrine glands of the integumentary system?

Answer 2

Produce sweat, oil, and wax to cool, protect, and moisturize the skins surface

Question 3

What are the functions of the integumentary system?

Answer 3

1. Protection against assaults from ultraviolet light and other mechanical, chemical and thermal agents
2. Provides a natural barrier against microorganisms
3. Prevents dehydration by reducing evaporation
4. Waterproofing
5. Reception of sensory information through receptors for touch, pressure, pain and temperature
6. Regulation of heat gain or loss
7. Supplying triglycerides- a major source of energy (hypodermis underneath the dermis)
8. Synthesis of vitamin D (absorption of calcium in the kidneys)

Question 4

What is the largest organ if the body?

Answer 4

Skin

Question 5

What are the 2 main layers of the skin?

Answer 5

Epidermis
Dermis

Question 6

What layer lies under the dermis?

Answer 6

Hypodermis or Subcutaneous tissue
Not actually part of the skin but serves as an anchor

Question 7

What tissue makes up the epidermis?

Answer 7

Consists of stratified squamous keratinized epithelium.

Question 8

Describe the dermis layer of the skin:

Answer 8

Thick layer of fibro-elastic connective tissue
Highly vascular, provides a source of nourishment to the epidermis
Receptor organs present

Question 9

What are the two layers of connective tissue, interwoven with one another that form the dermis?

Answer 9

The papillary dermis
The reticular dermis

Question 10

What is the subcutaneous layer of the skin made of?

Answer 10

Layers of loose connective tissue containing various amounts of adipose (fatty) tissue.

Question 11

What are the layers of cells in the thick skin? from superficial to deep

Answer 11

Stratum corneum
stratum lucidum
stratum granulosum
stratum spinosum, stratum basale

Question 12

What are the cells in the Stratum corneum, stratum lucidum, stratum granulosum, and stratum spinosum called?

Answer 12

keratinocytes

Question 13

What is a keratinocyte?

Answer 13

An epidermal cell that manufactures and stores the protein keratin

Question 14

What is keratin?

Answer 14

Intracellular fibrous protein that gives hair, nails, and skin their hardness and water-resistant properties.

Question 15

What cell is found in the stratum basale?

Answer 15

melanocytes

Question 16

What is the function of melanocytes?

Answer 16

Produce the pigment melanin
Gives hair and skin its colour and helps to protect the living cells of the epidermis from UV radiation damage

Question 17

What are the 2 layers of the dermis?

Answer 17

The papillary dermis
The reticular dermis

Question 18

What are the touch receptors in the papillary dermis?

Answer 18

Meissner corpuscles

Question 19

What makes up the papillary dermis?

Answer 19

loose, areolar connective tissue
collagen and elastin fibers of this layer form a loose mesh

Question 20

What makes up the reticular dermis?

Answer 20

thicker than papillary dermis
composed of dense, irregular connective tissue

Question 21

Describe the hypodermis?

Answer 21

1. Directly below the dermis and serves to connect the skin to the underlying fascia (fibrous tissue)
2. Not strictly a part of the skin
3. Well-vascularized, loose, areolar connective tissue and adipose tissue, which functions as a mode of fat storage and provides insulation and cushioning for the integument
4. Connects to underlining muscle and bone

Question 22

Describe lipid storage:

Answer 22

• Adipose tissue present in the hypodermis consists of fat-storing adipocytes
• Serves as an energy reserve
• Insulates the body to prevent heat loss
• Cushion to protect underlying structures from trauma

Question 23

what are the Integumentary system accessory structures?

Answer 23

Accessory structures of the skin include hair, nails, sweat glands, and sebaceous glands.

Hair and nails are modified forms of stratum corneum

Question 24

Describe hair:

Answer 24

keratinous filament growing out of the epidermis

Strands of hair originate in an epidermal invagination of the dermis called the hair follicle

At the bottom of the follicle - hair papilla lined with stratum germinativum (germinal matrix) which produces the hair

Hair bulb surrounds the papilla containing capillaries and nerve endings from the dermis

Question 25

what is the function of hair?

Answer 25

Protection Sensory input Thermoregulation Communication

Question 26

What is the function of Sebaceous glands?

Answer 26

Exocrine gland attached to hair follicle Produces sebum: fatty/oily substance that coats the hair and skin Natural lubrication Prevents moisture loss and pliability (prevents hair from becoming brittle) fatty acids of sebum also have antibacterial properties secretion of sebum is stimulated by hormones

Question 27

What glands are relatively inactive during childhood?

Answer 27

sebaceous glands

Question 28

What is the function of sweat glands?

Answer 28

Exocrine sudoriferous glands produce sweat to cool the body Develop from epidermal projections into the dermis and are classified as merocrine glands

Question 29

What are the 2 types of sweat glands?

Answer 29

Eccrine Sweat Glands & Apocrine Sweat Gland

Question 30

How is sweat secreted?

Answer 30

Excreted by exocytosis through a duct without affecting the cells of the gland

Question 31

Describe eccrine sweat glands:

Answer 31

Produces a hypotonic sweat for thermoregulation Found all over the skin’s surface Especially abundant on the palms of the hand, the soles of the feet, and the forehead Hypotonic and composed mostly of water, with some salt, antibodies, traces of metabolic waste, and dermicidin, an antimicrobial peptide Primary component of thermoregulation in humans, helps to maintain homeostasis

Question 32

Describe apocrine sweat galnds:

Answer 32

Associated with hair follicles in densely hairy areas, such as armpits and genital regions larger than eccrine sweat glands and lie deeper in the dermis, sometimes even reaching the hypodermis Duct normally emptying into the hair follicle Apocrine sweat includes organic compounds that make the sweat thicker and subject to bacterial decomposition and subsequent smell

Question 33

Describe nails and their function:

Answer 33

Specialized structure of the epidermis that is found at the tips of our fingers and toes Nail body is formed on the nail bed, and protects the tips of our fingers and toes as they are the farthest extremities and the parts of the body that experience the maximum mechanical stress Nail body is composed of densely packed dead keratinocytes Nail body forms at the nail root, which has a matrix of proliferating cells from the stratum basale that enables the nail to grow continuously

Question 34

What layer of the human skin synthesizes vitamin D when exposed to UV radiation?

Answer 34

epidermal layer

Question 35

Describe the Vitamin D synthesis process?

Answer 35

In the presence of sunlight, a form of vitamin D3 called cholecalciferol is synthesized from a derivative of the steroid cholesterol in the skin Liver converts cholecalciferol to calcidiol, which is then converted to calcitriol (the active chemical form of the vitamin) in the kidneys

Question 36

What is Basal Cell Carcinoma?

Answer 36

Form of cancer that affects the mitotically active stem cells in the stratum basale of the epidermis Most common skin cancer that occurs and is frequently found on the head, neck, arms, and back, which are areas that are most susceptible to long-term sun exposure Start in the stratum basale and usually spread along this boundary

Question 37

What is Squamous Cell Carcinoma?

Answer 37

Affects the keratinocytes of the stratum spinosum and presents as lesions commonly found on the scalp, ears, and hands Second most common skin cancer More aggressive than basal cell carcinoma, can metastasize

Question 38

What is melanoma?

Answer 38

Uncontrolled growth of melanocytes Typically develops from a mole Most fatal of all skin cancers Highly metastatic and can be difficult to detect before it has spread to other organs Appear as asymmetrical brown and black patches with uneven borders and a raised surface

Question 39

Describe the steps of identifying melanoma:

Answer 39

Asymmetry: the two sides are not symmetrical Borders:the edges are irregular in shape Color:the color is varied shades of brown or black Diameter:it is larger than 6 mm (0.24 in) Evolving: its shape has changed