Lesson 1: Anatomy of the Skin

Question 1

The outermost layer of the skin

Answer 1

Epidermis - rich in tough protein called keratin, avascular, waterproof barrier

Question 2

The layer of skin that lies immediately beneath the epidermis

Answer 2

Dermis - elasticity (resistance to stretching force) and strength (collagen) of skin, supplies epidermis with nutrients, role in thermoregulation

Question 3

The subcutaneous layer of skin

Answer 3

Hypodermis - not classified as part of the skin, connective tissue that contains fat, blood vessels, and sensory receptors, protective cushion and insulator, anchors skin to underlying bone or muscle

Question 4

Skin Color pigments

Answer 4

melanin, hemoglobin, and carotene

Question 5

Produced by melanocytes (located in the bottom layer of epidermis), protects skin and underlying tissue from harmful UV radiation

Answer 5

Melanin

Question 6

Oxygen-carrying molecule in RBC. When oxygenated, appears red

Answer 6

Hemoglobin

Question 7

A precursor of Vitamin A and produces yellow to orange color, stored in dermis and subcutaneous layer

Answer 7

Carotene

Question 8

The skin forms a very effective chemical, biological, and physical barrier.

Answer 8

Protection

Question 9

The skin plays a significant role in regulating body temperature, as 80% of heat is lost through the skin.

High temp - dilation of arterioles (causes the redness) and sweat glands secrete water, salt, and other substances

Low temp - constriction of arterioles (causes whitish hue)

Answer 9

Thermoregulation

Question 10

There are a number of sensations that arise from the skin in a process known as _______. These include touch, pressure, vibration, tickle, temperature, and pain.

Answer 10

Cutaneous sensation

Question 11

Metabolic waste products can be excreted from the body in small quantities via sweat (water and salt, as can ammonia and urea [breakdown of protein]), as well as CO2

Answer 11

Excretion

Question 12

The synthesis of vitamin D starts in the skin, triggered by ultraviolet light. Forms Vitamin D3 (cholecalciferol) –> liver and kidney transported by blood to turn into calcitriol

Answer 12

Vitamin D synthesis

Question 13

What are the four main types of cells in the epidermis?

Answer 13

keratinocytes, melanocytes, Langerhans cells, and Merkel cells.

Question 14

Epidermal cells that produce keratin and another substance that makes the skin waterproof. 90% of the epidermal cells. As they move up, they die and flake away

Answer 14

Keratinocytes

Question 15

Epidermal cells that produce melanin granules, absorb UV radiation, and are partly responsible for skin color

Answer 15

Melanocytes

Question 16

Epidermal cells that are part of the immune system

Answer 16

Langerhans cells

Question 17

Epidermal cells that form the border between the epidermis and the dermis. Associated with a sensory nerve ending, and together, they act as a slowly adapting touch receptor

Answer 17

Merkel cells (tactile cells)

Question 18

A tough and fibrous protein that serves to protect the skin

Answer 18

Keratin