1. The Epidermis Epidermis of aquatic organisms:
Cornified structures include:
-“______” of lamprey and hagfish
-____________________of land-going amphibians
-“_________” of tadpoles
-Distal …

2. The Epidermis Epidermis of terrestrial organisms:
Stratified layers gave rise to 2 categories of unique features…
1) Glands
2) Stratum corneum

3. The Epidermis Epidermis of terrestrial organisms:
Glands fall in 2 main categories based on shape… 1) 2)

4. The Epidermis Epidermis of terrestrial organisms:
Glands produce their secretions via 3 main modes…
1) Cell membrane (_____________)
2) Whole cells and their contents (_____________)
3) Cell fragments (_____________)

5. The Epidermis Epidermis of terrestrial organisms:
Mucous glands not abundant… occur in areas with need for lubrication
Why not abundant on terrestrial animals?
What other skin structures would interfere?
What areas need lubrication?

6. The Epidermis Epidermis of terrestrial organisms:
Granular glands found mainly in terrestrial amphibians and reptiles
Can produce ____________ and some ____________________
Concentrations of “noxious” granular glands found on “warts” and ___________________of toads
Lizards have ___________________
Musk or ________________ in turtles and snakes

7. The Epidermis Epidermis of terrestrial organisms (birds):
Few integumentary glands in birds… however, avian oil glands
_______________ gland at rump, large in aquatic birds and some domestic birds
Oil glands also line …
Sometimes found around the …

8. The Epidermis Epidermis of terrestrial organisms (mammals):
2 major types of glands in mammals…
(oil glands)
2) (sweat glands)

9. The Epidermis Epidermis of terrestrial organisms (mammals):
_________________(saccular) usually associated with hair.
Exceptions...
Sebum secreted into hair follicle
Modified (_______________) in ear canal to secrete _______
___________________ keep conjuctiva moist (plugged = ________________)

10. The Epidermis Epidermis of terrestrial organisms (mammals):
_________________________ (coiled tubular glands)
Evaporative cooling primary function of _________ sweat glands
Found in least hairy regions
Some mammals lack sweat glands
Humans have greatest # per cm2
___________ sweat glands involved with secondary sex characteristics

11. The Epidermis Epidermis of terrestrial organisms (mammals):
Scent glands can be sebaceous or sudoriferous
Found in varying locations…

12. The Epidermis Epidermis of terrestrial organisms (mammals):
___________________ present in both sexes and derived from a line of ectoderm called the _____________________
This tissue invades the dermis and spreads
Distinct tissue above these glands develops (____________)

13. The Epidermis Epidermis of terrestrial organisms (mammals):
Nipples can be multiple… -
Different species… different placement

14. The Epidermis Epidermis of terrestrial organisms (mammals):
During lactation, products accumulate in _____________ (usually)
Suckling releases _____ and _____________ facilitates by causing smooth muscle contractions
“_____________” reflex

15. The Epidermis Stratum corneum:
Epidermal scales found only in _____________.
Squamates (snakes & lizards) thickened corneum except at …
Varying forms… _________, ____, __________, _________
Birds have epidermal scales on areas lacking feathers
What about mammals?

16. The Epidermis
Stratum corneum:
Thick skin

17. The Epidermis Claws, hoofs and nails: Claws appeared in basal amniotes
Tigers have claws… are they homologous to those of Idaho Giant Salamanders?

18. The Epidermis Claws, hoofs and nails:
Claws, nails and hooves homologous
Similar structure… *
Birds can have claws on wings too
Are claws shed or worn down?

19. The Epidermis Feathers: 3 basic types… *
Feathers comprised of a quill (_________), _____ and ________. Parallel extensions from the shaft barbs are crosslinked with ________ (hooklets and flanges)

20. The Epidermis Feather development:
_____________induces overlying ____________ to divide mitotically… resulting bump is called _____________________
Why is presence of papillary vasculature important?
Tall columns form a _______________and push toward tip, becoming barbs

21. The Epidermis Feather development:
When the barbs are still in protective feather sheath it is called a ________________
At feather maturity… bulk of papilla dies back
Basale tissue retracts and then starts over again
Developing feathers push old feathers out
_____________________

22. The Epidermis Feather origins:
Feather origins:
One hypothesis is that they are derived from reptile scales… Sinosauropteryx
Early development of dermal papilla is similar but remaining scenario is not
Some propose they are novel structures

23. The Epidermis Hair: Functions of hair…
Hair:
Functions of hair…
_________________ (underfur and guard hairs)
__________(vibrissae)
__________ (spines and quills)

24. The Epidermis Hair morphology:
Similar to feathers in that there is a ___________
__________has ________ __________ with much mitosis
__________is portion under the dermis where cells are dying
__________is portion of hair that is separate from follicle wall

25. The Epidermis Hair morphology: Thin outer covering is the ___________
Underlying zone called ___________
Inner pith is the ________
Smooth muscle associated with the follicle and originating in the dermis is the ______________

26. The Epidermis
Horns: *

27. The Epidermis Baleen and miscellaneous:
*Toothless whales (mysteceti) rely on __________ to filter fish and/or crustaceans (krill) *

28. Integuments by Taxa Agnathans:
Epidermis… stratified, unicellular glands, mitotically active throughout
Dermis… thinner than epidermis but dense/tough

29. Integuments by Taxa Cartilaginous fishes:
Epidermis… stratified, multicellular glands show up
Dermis… ______________ and melanophores

30. Integuments by Taxa Bony fishes: Epidermis… many mucous glands
Dermis… dermal bone/scales

31. Integuments by Taxa Amphibians:
Epidermis… stratified, multicellular glands (mucous and granular)
Dermis… attached to musculature in some, loose in others, presence of chromatophores

32. Integuments by Taxa Non-avian reptiles:
Epidermis… stratified, thick stratum corneum (scales)
Dermis… tough, some with dermal bone

33. Integuments by Taxa Birds:
Epidermis… thin, lacks glands (except uropygial), modified epidermal layers to form feathers (scales)
Dermis… thin, arrector pili muscles

34. Integuments by Taxa Mammals:
Epidermis… Distinct strata, variety of glands, hair
Dermis… exceptionally thick and tough