Structure and Function of Skin

Question 1

What are the two parts to the Integumentary System?

Answer 1

The Cutaneous Membrane (skin) and the Accessory Structures

Question 2

What is the Cutaneous Membrane comprised of?

Answer 2

The Outer Epidermis and the Inner Dermis

Question 3

Where is the Subcutaneous Layer located?

Answer 3

Below the Inner Dermis

Question 4

What are the functions of the Skin?

Answer 4

• Protects underlying tissues and organs
• Excretes salts, water and organic wastes (glands)
• Maintains body temperature (insulation and evaporation)
• Synthesizes Vitamin D3
• Stores lipids
• Detects touch, pressure, pain and temperature
• Produces melanin
• Produces keratin

Question 5

What are the three cells of the Epidermis?

Answer 5

• Keratinocytes
• Basal cells
• Melanocytes

Question 6

What is Skin Colour influenced by?

Answer 6

• Carotene (Pigment)
• Melanin (Pigment)
• Blood Circulation (Red Blood Cells)

Question 7

What type of Tissue is the Epidermis?

Answer 7

Avascular Stratified Squamous Eptihelium

Question 8

How do Nutrients and Oxygen get to the Epidermis?

Answer 8

Nutrients and Oxygen diffuse from Capillaries in the Dermis

Question 9

What is the the most abundant cell in the Epidermis and what is their purpose?

Answer 9

Keratinocytes have the purpose of containing large amounts of Keratin

Question 10

What’s the purpose of Melanocytes

Answer 10

To produce Melanin

Question 11

What is Keratinisation and how long does it take to happen?

Answer 11

• The formation of a layer of dead, protective cells filled with Keratin
• It takes roughly 7-10 days for a cell to move from the deepest layer to the surface

Question 12

In which area of the body would you expect to find an especially thick stratum?

Answer 12

In the sole of your hands and foot

Question 13

The Epidermis provides a Physical Barrier due to the presence of?

Answer 13

Keratin

Question 14

What are the colours of the two pigments and where do they occur?

Answer 14

• Carotene has a Orange-Yellow pigment accumulating in the epidermal cells and fatty tissues of the dermis
• Melanin is a Yellow-Brown or Black Pigment produced by Melanocytes

Question 15

What’s the Function of Melanocytes?

Answer 15

They produce Melanin which serves to protect the skin from sun damage from UV Radiation

The melanin production is what decides Skin Colour, not the number of Melanocytes.

Question 16

How do Capillaries influence Skin Colour?

Answer 16

The oxygenated Red Blood contributes to skin colour

Blood vessels dilate from heat moving the heat to the surface of the skin hence creating a reddish appearance. When blood flow decreases skin becomes pale.

Cyanosis is where there is a severe reduction in blood flow or oxygenation and gives a Bluish Skin Tint as a result.

Question 17

Which cells Produce Vitamin D3?

Answer 17

The Epidermal Cells

Question 18

What are the two organs that convert Vitamin D into a substance that helps with the absorption of Calcium and Phosphorus?

Answer 18

The Liver and Kidneys convert Vitamin D into Calcitrol

Question 19

What purpose does the Dermis serve?

Answer 19

To Anchor Epidermal Accessory Structures such as hair follicles and sweat glands

Question 20

What are the two components of the Dermis?

Answer 20

• Outer Papillary Layer

- Deep Reticular Layer

Question 21

The Dermis supplies the skin with nerves, what does this help with?

Answer 21

• Blood Flow
• Gland Secretion
• Monitor Sensory Receptors

Question 22

What does the Papillary Layer consist of?

Answer 22

• Areolar Tissue

- Contains smaller Capillaries, Lymphatics and Sensory Neurons

Question 23

What does the Reticular Layer consist of?

Answer 23

• Has Dense Irregular Connective Tissue
• Contains larger blood vessels, lymph vessels, and nerve fibres
• Contains Collagen and Elastic Fibres

Question 24

What is the purpose of the Hypodermis/ Subcutaneous Layer?

Answer 24

• Stabilises the skin
• Made up of Loose Connective Tissue
• It is the site of Subcutaneous Injections