Integumentary System

Question 1

Understand the layered composition of skin

Answer 1

Composed of two layers:
- Epidermis – outermost, thinner layer composed of
epithelial cells

• Dermis – deeper, thicker layer composed of dense
  connective tissue, only the dermis is vascularised
• Hypodermis (superficial fascia): subcutaneous tissue deep to skin

Question 2

Explain the developmental origins of the epidermal and dermal layers of skin

Answer 2

• The epidermis is derived from ectoderm
• Dermis and hypodermis arise from mesoderm
• By end of fourth month of development, skin is
  well-formed (fingerprints have developed)
• Epidermis:
  o Consists of 5 distinct layers (superficial to deep):
   Stratum basale (basal layer)
   Stratum spinosum (prickly layer)
   Stratum granulosum (granular layer)
   Stratum lucidum (clear layer)
   Stratum corneum (horny layer)
  o most superficial layer is comprised of dead cells

Question 3

Describe the major features of the epidermis, dermis including their distinct layers and blood supply

Question 4

Understand the significance of dermal tension lines

Question 5

Describe the major features of subcutaneous tissue

Question 6

Describe the major features of accessory structures of the skin including hair, nails and sebaceous and sweat glands

Question 7

List the types of sensory receptors found in the dermis

Question 8

Describe the process of somatic sensation and referred pain

Question 9

Understand the significance of dermatomes

Question 10

Describe clinical examples of damage to the skin

Question 11

Give a brief overview of the integumentary system

Answer 11

• Consists of skin, hair, nails, sweat and sebaceous
  glands and sensory receptors
• Wide variety of functions:
  o Regulated body temperature
  o Stores blood
  o Protection from the external environment
  o Excretes and absorbs substances
  o Synthesises vitamin D (skin)
  o Detects cutaneous sensations