THE INTEGUMENTARY SYSTEM

Question 1

What is the Integumentary System

Answer 1

The covering of skin and accessory structures (sweat & oil glands, hair and nails)

Question 2

What are the 3 main areas of the skin

Answer 2

Epidermis, Dermis, Hypodermis

Question 3

What does the Subcutaneous layer do?

Answer 3

It helps with the framework for the skin using fats. (not truly skin)

Question 4

What are the sublayers of the Dermis

Answer 4

Papillary and Reticular

Question 5

What are the 4 types of Epidermal Cells

Answer 5

Keratinocytes, Melanocytes, Dendritic (Langerhans), Tactile (Merkel)

Question 6

What is the Function of Keratinocytes

Answer 6

It gives the skin; waterproofing, strength, and sturdiness to withstand trauma.

Question 7

Keratinocytes (life cycle)

Answer 7

come from stem cells that sit by dermal papillae, and actively divide. They have a life span of 25-45 days and will move up throughout that time.

Question 8

What hormone will help stimulate keratinocyte production?

Answer 8

EGF, will stimulate mitotic activity

Question 9

What is the function of a Melanocytes

Answer 9

to produce melanin for UV radiation protection

Question 10

How do Melanocytes work?

Answer 10

Once melanin is produced it is packed into melanosomes, which will branch numerous times until transferring to adjacent cell

Question 11

Linking between Keratinocytes and Melanocytes

Answer 11

Keratinocytes collect the product of melanocytes (melanin) before moving upwards. This is done in order to protect us against UV radiation

Question 12

How often does our skin shed

Answer 12

The skin turns over once a month, we lose 1.6 pounds of shed skin a day
(slower when older -> wrinkles)

Question 13

What is the function of Dendritic (Langerhans) cells

Answer 13

Very first line of defence of immune system, and will signal rest of immune system of bacteria, virus, or fungi within the body (from particular area)

Question 14

What is the function of Tactile (Merkel) cells

Answer 14

Are the touch receptors of the body, and will give information to the CNS (certain areas are more sensitive.

Question 15

What is the proper order of Epidermal cells and layers of the epidermis? (Superficial to deep) - THICK

Answer 15

Stratum Corneum, Stratum Lucidum, Stratum Granulosum, Stratum Spinosum, Stratum Basale

Question 16

What layer isn’t in thin skin? (Epidermal Cells and layers of epidermis)

Answer 16

Stratum Lucidum

Question 17

Why does thick skin have more layers than thin skin?

Answer 17

Because it is found in higher-abrasion areas such as hand and feet

Question 18

What is the dermis?

Answer 18

A strong, flexible connective tissue, thats embedded with collagen, elastic, and reticular fibers. It contains nerves, BV, lymphatic vessels, hair follicles, oil and sweat glands

Question 19

What types of Cells are found in the dermis?

Answer 19

Fibroblasts, dermal, macrophages, and sometimes mast cells (histamine), and WBCs

Question 20

Define the Papillary Layer

Answer 20

interwoven mat of areolar CT fibers interspersed with BV

Question 21

Define the Dermal Papillae

Answer 21

Superficial region of the dermis that indents the overlying epidermis, it supplies the epidermis with nutrients and allows for tactile receptors

Question 22

What are Friction Ridges

Answer 22

On the palms of hands (fingers), soles of feet, dermal papillary lie on top of dermal ridges, which give rise to epidermal ridges

Question 23

What do Epidermal Ridges (friction ridges) do?

Answer 23

enhance gripping ability, contribute to sense of touch, sweat pores in ridges leave unique finger patterns

Question 24

Fun Facts about Friction Ridges

Answer 24

Pre-birth development Can only disappear if scarring, all are different

Question 25

Define the Reticular Layer

Answer 25

deeper + thick dense irregular CT, source of lines of cleavage (tension) lines, collagen fibers give strength & resiliency & maintain skin hydration, elastic fibers provide stretch-recoil

Question 26

What is a Cleavage (tension) Lines

Answer 26

Indicate the direction of orientation of the underlying collagen fibers

Question 27

Going with cleavage line vs going against cleavage limes

Answer 27

With: not subjected to stress, won’t gap, will heal and scar nicely
Against: subjected to stress, will cause gapping, will heal poorly, and scar