Integument Flashcards
What are some protective functions of the integument?
Exclude microbes and pathogens
Prevent abrasions to underlying tissues
Produces protective elements (bones, quills, toxins, horns, claws)
Helps to advertise unpalatability
Helps to conceal
Protect from solar radiation and moisture loss
What are the general functions of the integument?
Protection Regulation and exchange Nutrition Locomotion Sensory Communication
What is another name for the hypodermis? What is it comprised of?
superficial fascia
comprised of loose connective & adipose tissues
What is the epidermis derived from? Give some examples of what it produces.
From the ectoderm
ex. hair, feathers, baleen, claws, nails, horns, beaks, some scales
What is the dermis derived from? Give some examples of what it produces.
From the mesoderm
ex. osteoderms and other dermal bone of reptiles
What does the epidermis + dermis produce?
teeth, denticles, scales of some fish
What makes up the stratum corneum?
Keratin (produced by keratinization of keratinocytes)
What is the difference between alpha and beta-keratins? Give examples of each. What types are present in synapsids?
alpha is soft - flexible epidermal layers
beta is hard - hard scales, claws, beaks, feathers
Synapsids only have alpha keratins
What is a callus?
An elaborated stratum corneum from constant mechanical stimulation
What are some regulatory and exchange functions of the integument?
water balance thermal balance salt & ion balance help to void metabolic wastes involved in respiration
Describe the integument of hagfish and lampreys.
no dermal bone or scales
epidermis contains numerous stacked layers of epidermal cells
What are club cells? Where are they located?
unicellular gland that release alarm chemicals
located in epidermis (lamprey)
What is a granular cell? Where are they located?
gland that contributes to the production of mucous layer
located in epidermis (lamprey)
What is unique about Hagfish skin?
dermis contains slime glands. Thread protein encapsulates water.
What is unique about Chondrichthyes skin?
dermal bone is absent but surface denticles (placoid scales) persist to reduce drag and thus increase speed.
What is unique about Amphibian skin?
Skin is very thin & important for respiration.
Mucous and Poison glands in dermis
What is unique about Tiger keelback snakes?
They can eat toads and store their poison in their own neck
What is a Leydig cell? Where is it located?
Secretes substances that resist entry of bacteria or viruses. In the epidermis of Amphibians
What are calluses called on male amphibians? What is their purpose?
Nupital pads – epidermal expansion to enhance grip on female during reproduction.
What are Gastralia? Where are they found?
abdominal ribs (dermal bone). In reptiles
What are Osteoderms? Where are they found?
(dermal bone) located under epidermal scales. Found in crocodilians, some lizards, & parts of turtle shells
Where are integumental glands located in reptiles?
Limited to certain areas. ex. femoral glands of lizards
Describe the integument of Birds.
Skin contains keratinized surface layer (stratum corneum)
Epidermal scales on legs and feet
Feathers
Describe the different parts of a feather.
Calamus (quill) -> Barb -> Rachis -> Vane -> Spathe
