BIOL 204 Study Guide - Final Guide: Stratum Basale, Onchocerciasis, Basement Membrane
Function of skin?
Flexibility in motion
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Invasion protection
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Minimize water loss
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Epidermis
Made of epidermal ectoderm
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Linked to dermis via. Basement membrane
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Stratum germinativum
Where new cells are formed
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Innermost layer of epidermis
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Pushed out when old cells are worn away
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Stratum corenum
Dead and keratinized epidermal cells
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Keratin cells produce keratin and are self-destructive
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Keratin Structures
Epidermal Scales
Continuous layer of repetitious thickening
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Found in most amniotes
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Moulting or small flakes
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Snake skin, lizard skin, turtle scales, beaver tail,
bird legs
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Claws and Talons
Curved and laterally compressed projections
from digits
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Found in many amniotes
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Hooves
Ends of ungulate digits □
Enlarged keratinized plates □
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Nails
Produced at nail base and pushes existing cells
forward
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Protect mechanical injury□
Strong grip for grasping□
Found only in primates□
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Horn Sheath
Core of dermal bone with a keratinized cover□
Can be present year round or grow throughout
animal's lifetime
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Found in Bovines (horned mammals)□
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Baleen
Plates that arise from oral epithelium□
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Beaks
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Feathers
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Dermis
Made of dermatome epimere mesoderm
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Integument
Tuesday, April 3, 2018
10:19 PM
