integumentary system study guide

(not done)

What is the name of the layer that lies below the dermis? What is it composed of?

HYPODERMIS LAYER - composed mostly of adipose tissue

Please review the functions of the Integumentary System

• Protects deeper tissues from

  • Mechanical damage (bumps)

  • Chemical damage (acids and bases)

  • Bacterial damage

  • Ultraviolet radiation

  • Thermal damage

  • Desiccation

• Aids in body heat loss or heat retention

• Aids in excretion of urea and uric acid

• Synthesizes vitamin D

What type of tissue is the epidermis composed of?

Stratified squamous epithelium

What is the role of melanin

Forms a pigment umbrella over the “sunny side” of their nuclei to protect DNA

What is the role of keratin?

a protective protein that prevents water loss from skin

What are examples of places in the body where we may find stratum lucidum?

Palms of hands & soles of feet

What are the two layers of the dermis?

Papillary layer (upper dermal region) - dermal papillae: some contain capillary loops and others house pain and touch receptors

Reticular layer (deepest skin layer) - blood vessels, sweat and oil glands and deep pressure receptors

What are the differences between the various types of glands that were discussed?

Sweat glands: produce sweat and widely distributed in skin

Sebaceous glands: produce oil (lubricant for skin, prevents brittle hair and kills bacteria) & are activated at puberty

What are the differences between eccrine and apocrine sweat glands?

Eccrine: open directly on skin surface, helps with cooling the body and it is activated from birth 

Apocrine: opens into hair follicles, produce thicker sweat, becomes active at puberty, can smell when broken down by bacteria (body odor)

What makes up sweat from the eccrine glands?

99% water with the rest being NaCl and K+

What are the arrector pili muscles? Please be able to identify and also discuss what their function is within the dermis.

Smooth muscle that pulls hair upright when cold or frightened

What is the role of melanin in protection against UV radiation

Prevents too much damage to the DNA and lessen the risk of cancer

What role does sweat play in maintaining homeostasis

It regulates body temperature through evaporative cooling. When the body overheats from exercise or hot environments, sweat glands release sweat, and the evaporation of sweat from the skin’s surface dissipates heat, which helps maintain a stable internal temperature

What is the rule of 9s and how is it used to diagnose the severity of a burn

It is divided into 11 areas that each represents 9% of total body surface area. The higher the percentage, the more severe the burn is. 

1. MILD - less than 10%

2. MODERATE - 10-20%

3. SEVERE - more than 20%

how do nutrients reach the surface of your skin?

Nutrients travel via blood in the dermis → then diffuse into the epidermis to nourish skin cells

what is the difference between the Meissner’s corpuscle and pacinian corpuscle

Meissner’s corpuscle - found near skin surface, senses light touch and texture

Painian corpuscle - found deeper in skin, senses deep pressure and vibration