Integumentary System Exam 2 Flashcards
What is the skin beneath the toes and foot specialized to withstand?
- Compression from standing.
- Abrasion from contact with rough surfaces.
What is the skin on the bottom of the foot described as?
Thick but flexible.
What are the two parts of the beak?
- Internal skeleton of bone.
- Closely attached layer of highly keratinized skin over the bony skeleton.
What is the epidermis of the beak called?
The rhamphotheca.
What is the rhamphotheca described as?
Thick and horny.
What is the egg tooth made of?
Strongly calcified keratin cells.
What are the claws made of?
Keratinized epidermis.
What does the claw root epidermis give rise to?
Flattened, keratinized cells that remain firmly stuck together.
What are the wattle and the comb referred to as?
Accessory sexual epidermal appendages.
What do the wattle and comb develop as a result of?
Production of sex hormones.
Why are the wattle and comb bright red?
They are rich with blood vessels.
What do chickens do with the wattle and comb when it is hot outside?
Dip it in water to aid in cooling.
What is the preen gland described as?
Two-lobed, pea-sized structure that develops from the epidermis at the base of the tail.
What does the preen gland discharge?
A fatty secretion.
What type of secretory gland is the preen gland?
Holocrine.
How is the fatty secretion created in the preen gland?
Cells get pushed to the middle as new cells form and the old cells break down.
What is contained in the preen gland secretion?
- Non-saponifiable lipids.
- Saponifiable lipids.
- Lecithin.
- Cell breakdown products.
What are lecithins?
A special phosphorous compound.
What are saponifiable lipids?
Special fats that can be broken down by an alkali.
In what types of birds are preen glands most important?
Aquatic birds.
*They develop earlier in aquatic birds.
What are the area that feathers are confined to called?
Pteryla.
What are areas devoid of feathers called?
Apteria.
How do feathers increase in volume to trap air to keep warm?
Smooth muscles attached to the feather follicle contract, causing the feathers to become erect.
*It also works to release heat.
What are the 5 types of feathers?
- Contour feathers.
- Plumules.
- Filo-Plumules.
- Down (chicks).
- Bristles.
What are the 9 parts of the contour feather?
- Shaft or rachis.
- Outer vane and inner vane or vexillum.
- Parallel barbs.
- Barbules.
- Barbicels or hooklets.
- Calamus or quill.
- Superior umbilicus.
- Inferior umbillicus.
- After shaft or hypo-rachis.
How is the rachis described?
- Four-sided.
- Tapering.
- Elastic.
- Possess a longitudinal groove facing towards the body when the feathers are in the normal position.
How is the vexillum described?
Sloped obliquely towards the tip.
What does each barb contain?
Two rows of barbules, a proximal row and a distal row.
Where is the distal row of barbules growing from?
The side of the barb facing towards the tip of the feather.
*Has microscopic hooklets that hook onto the proximal barbules of the next barb.
How are hooklets described?
Hold the barbs together to form the vane.
What does the interlocking between barbs allow?
A strong, continuous, smooth surface.
How is the quill described?
- Transparent.
- Rounded.
- Hollow.
- Series of conical scales on the interior.
How is the inferior umbilicus described?
Forms a papilla of epidermis during feather formation, leaves hole at proximal end of feather.
How is the superior umbilicus described?
Hole in shaft at junction of shaft and vanes.
How is the hypo-rachis described?
A small feather-like tuft.
What are the main wing feathers called?
Remiges.
Which part of the vane of remiges is broader, the anterior portion or posterior portion?
The posterior portion.
What are the two types of flight feathers?
- Primary flight feathers.
- Secondary flight feathers.
Where are primary flight feathers located?
On the trailing edge of the outer part of the wing.
Where are secondary flight feathers located?
In the same area as primary feathers, just closer to the body.