Integumentary System Exam 1 Flashcards
What is the dorsal directional term pertaining to?
The upper surface of the animal.
What is the ventral directional term pertaining to?
The lower and abdominal surface.
What is the cranial/anterior directional term pertaining to?
The front or head.
What is the caudal directional term pertaining to?
The tail or rear.
What does the integumentary system consist of?
- Skin.
- Appendages (beak and claws).
- Feathers.
What is unique about the integumentary system as compared to other systems?
It covers the entire body.
In what two locations in the integumentary system are glands found?
- The outer ear canal.
- Preen gland, base of tail.
What is the preen gland used for?
Keeping the feathers oiled.
What are the importance of the comb and wattle?
Thermoregulation.
What are the functions of the integumentary system?
- Barrier against external environment.
- Support and protection from infection and physical injury.
- Thermoregulation.
- Senses.
- Compounds capable of being turned into vitamin D in the presence of sunlight.
- Pigments for display and protection from elements.
What are the three tissue layers that compose the integumentary system (outermost to innermost)?
- Epidermis.
- Dermis or corium.
- Hypodermis.
What two layers of skin contain widely spaced cells intermixed with connective tissue?
- Dermis.
- Hypodermis.
What is the epidermis primarily composed of?
Stratified squamous epithelium.
What is unique about this outer layer?
It is continuously replaced by cells created by mitosis in the epidermal germinative layer.
What are the three layers of the epidermis from outermost to innermost?
- Flattened, horny cells.
- Transitional layer.
- Columnar layer.
What happens in the transitional layer?
Cells from the columnar layer become hard and horny.
What happens in the columnar layer?
Where all of the cells for the outermost layers of the epidermis are created.
What is the dermis described as?
Relatively thin and uniform.
What are the main components of the dermis?
Collagen with some elastin.
In what layers of the skin adipose tissue found?
The hypodermis.
What do the air spaces in the hypodermis connect with?
Air sacs of the respiratory system.
*Enhances flight ability.
What are shed epidermal cells referred to as?
Dander or scurf.
What does dander/scurf aid in the survival of?
- Parasites like lice.
- Disease causing viruses like Marek’s Disease.
What is keratinization?
The synthesis of the very durable fibrous protein keratin.
What is required for keratinization to be complete?
The cell must die.
What 2 important supplies are found in the dermis?
- Nerve (Outer layer).
- Blood vessels.
How do nutrients, hormones, gases, and other compounds reach the living cells in the epidermal layer?
Diffusion.
What is the main characteristic of skin covered by feathers?
It is thinner due to being protected.
On what areas of the body is the skin more tightly joined to the underlying tissue?
Over the thighs and wings.
What areas of the body are covered by scales?
The lower legs and upper sides of the toes.
Where doe the feathers grow from in breeds with feathered legs?
The margins of the scales.
What protein are the scales rich in?
Keratin.
*Carry over from reptilian ancestors.
