Structure of the Skin Flashcards
How are blisters formed? (2)
- Burn or friction may cause the epidermis and dermis *2 layers) to separate
- Interstitial fluid accumulates between the layers → blister
What does hypodermis composed of and what purposes does it serve? (4)
- Adipose tissue (fat)
- Shock absorber
- Insulates deeper tissue from extreme temperature changes
- Responsible for curves of the body (feminine feature)
List the 3 substances that determine skin colour. (3)
- Melanin (amount and kind)
- Carotene (amount)
- Oxygen-gen rich hemoglobin (amount in the dermal blood vessels)
What substance are most of the cells in the epidermis made out of?
Keratin
Define: cyanosis
Appearance when hemoglobin is poorly oxygenated, skin and blood take on a blue tint most notably on lighter-coloured skin
Under what condition is cyanosis common?
Heart failure
What do emotions influence in relation to the skin?
Skin colour
List 5 reasons why skin may redden (erythema). (5)
- Embarrassment
- Fever
- Hypertension
- Inflammation
- Allergy
What is pallor?
Blanching of the skin
What may result in pallor (blanching)? (5)
- Fear
- Anger
- Anemia
- Low BP
- Impaired blood flow to the area
What does jaundice look like?
Yellow cast
What may jaundice signify and why does it turn skin yellow? (2)
- Signifies liver disorder
2. Bile pigments accumulate in the blood and circulate throughout the body → deposit into body tissues
List the 3 parts that act as appendages to the skin. (3)
- Hair
- Hair follicles
- Cutaneous glands
What do exocrine glands do?
Release secretions to the skin surface via ducts
Differentiate between sebaceous glands and sweat glands. (2)
- Sebaceous glands secrete OIL
2. Sweat gland secrete SWEAT (and thus, are “sudoriferous”)
What is sebum composed of and what does it do? (4)
- Mixture of oily substance and fragmented cells
- Acts as a lubricant to keep skin soft and moist
- Prevents hair from becoming brittle
- Protects the body with chemicals that kill bacteria
What is the common name for seborrhea and what is it essentially? (2)
- Seborrhea = cradle cap
2. Overactive sebaceous (oil) glands
Where are sweat glands?
All over the body
Differentiate between the eccrine and apocrine sweat glands. (2)
- Eccrine is all over the body
2. Apocrine is only in the armpit (axillary) and genital areas
State the composition sweat. (5)
- Water
- Salts
- Vitamin C
- Traces of metabolic wastes
- Lactic acid
What is the pH range of sweat and does this mean it’s acidic or alkaline? (2)
- pH range = 4-6
2. Acidic
Are apocrine glands bigger or smaller than eccrine glands?
Bigger
Where the the ducts of apocrine glands empty into?
Hair follicles
What does sweat from apocrine glands contain? (3)
- Everything from eccrine sweat
- Fatty acids
- Proteins
List 3 things that activate the nerve fibers when apocrine glands secrete sweat. (3)
- Pain
- Stress
- Sexual arousal
