The Integumentary System Flashcards
What is the integumentary system?
The largest organ system in the body.
What is the integumentary system composed of?
The skin and it’s appendages, such as hair, scales, feathers, hooves and nails.
List the functions of the integumentary system.
•Protection
•Sensation (Sensitivity)
•Secretion
•Absorption
•Excretion
•Cleaning
•Friction reduction
•Dehydration
•Ultraviolet light
What are the 3 basic layers of the skin?
- Hypodermis: Deepest layer responsible for making new skin cells.
- Dermis: Middle layer of maturing cells.
- Epidermis: Outer-most superficial skin layer, one of the skin layers that sheds dead cells.
Additional info: Every single skin cell, including those of the deepest layer, are replaced by new cells in a 3 week period.
COMPONENTS OF THE SKIN
Sebaceous glands: Secrete sebum to lubricate and waterproof the skin and hair of mammals.
Sudoriferous glands: Secrete sweat to aid thermoregulation. In ears, there are ceruminous glands that secrete ear wax and protect ear canal from physical damage and pathogens.
Hair follicles: Produce hair that aids thermoregulation.
Blood vessels: Nourishes cells and removes waste products.
TOUCH RECEPTORS
Mechanoreceptors:
Vibration and touch (touch) , meissner’s corpuscles (light touch) and pacinian corpuscles (pressure).
Nociceptors:
Pain and free nerve endings.
Thermoreceptors:
Temp, vasodilation/construction of blood vessels and sweating.
What is hair composed of?
A tough protein called Keratin, which is produced inside specialised cells called Keratinocytes.
What are the two types of hair found in animals?
Downy hair: Soft, kinked and dense which lies close to the skin. Undercoat essential for insulation.
Guard hair: Long, thick and coarse which makes top coat. Protects underlying skin and influences animal’s appearance.
For every 1 guard hair, it is surrounded by 6-12 downy hairs.
What are hair, claws, hooves and antlers made from?
Keratin.
