Module 7: Animal Integument Flashcards
is the outer covering of the animal body, a protective wrapping
Integument
What is included in integumentary system
- Skin
- All structures derived from or associated with such as hair, setae, feather and horns
Functions of Integumentary System
- Protective wrapping
- Regulatory and Excretory functions
- Sensory functions
- Behavioral interactions between individuals
– mechanical protection against abrasion and puncture
– effective barrier against bacteria
– moisture proofing against fluid loss or gain
– protect underlying cells against UV
Protective wrapping
Osmo-and Thermoregulation, due to the presence of sweat glands and other structures.
Regulatory and Excretory Functions
Integument has a variety of sensory receptors that can detect pain, touch, heat, pressure, etc.
Sensory functions
Senses heat or cold
Thermo-receptor
senses “touch”
Meissner’s corpuscle
Senses pain
nociceptor
Senses “pressure”
Pacinian corpuscle
-Pigmentation usually affects how individuals interact with other individuals or species.
Behavioral interactions between individuals
What signals indicate wheter the snake is venomous or not
Coloration signals
Red touches _____, your OK jack
Black (Harmless) (King snake)
Red touches ____, You’re a dead fellow
Yellow (Deadly) (Coral Snake)
Integumentary system in Invertebrates
- Plasma membrane
- Epidermis
Many protozoans have only a delicate ___
Cell or plasma membrane
uses of cell or plasma membrane for many protazoans?
External Coverings
functions for gas exchange, waste removal by simple diffusion, and uptake of dissolved nutrients
Protozoan integument
What did some protazoans developed?
A protective pellicle
By definition it is a THIN skin or film covering for certain protozoans
Pellicle
It is made up of a single layer of columnar epithelial cells
Epidermis
It is the principal covering
Single layered Epidermis
Epidermal integument is delicate and soft in mollusks and contain mucous glands, which secrete the calcium carbonate of the shell.
Molluscan Integument
What does epidermal integument in mollusks contain?
Mucous glands, which secrete the calcium carbonate of the shell.
What does mollusks integument consists?
- Cuticle
- Simple epidermis
- Layer of connective tissue
- layer of reflecting cells
- Thicker layer of connective tissue
Iridocytes
layer of reflecting cells
arthropods have the most complex of integuments because their integument can also perform
Skeletal functions
One of the defining feature of arthropod integument
Hardening of cuticle layer
Different Means of hardening Processes that act on procuticle layer
- Calcification
- Sclerotization
deposition of calcium carbonate in the outer layers of procuticle, which is observed in crustaceans.
Calcification
protein molecules (sclerotin) bond together with stabilizing cross-linkages within and between adjacent lamellae of the procuticle
Sclerotization
is tough, highly resistance and water insoluble.
Sclerotin
Where is sclerotization observed?
In insects
uses their integument as an exoskeleton
Arthropods
Disadvantage of exoskeleton
- In ability to grow with the animal
the shedding process of exoskeleton
Molting or ecdysis
The process of Molting in arthropods
- epidermal cells divide by mitosis
- epidermis secretes enzyme to digest procuticle
- absorption of digested materials
- new epicuticle and procuticle formed
- new cuticle is thickened and calcified or `sclerotized.
Invertebrate integument
Exoskeleton
The vetebrate integument
Skin
Two main layers of skin
- Epidermis
- Dermis
- Hypodermis
Albeit not part of the skin, consists of loose connective tissue, adipose tissue, and nerve endings, separates the skin from the deeper tissues
Hypodermis
is made up of stratified keratinized squamous epithelium
The epidermis
What does the epidermis made up of?
Stratified keratinized squamous epithelium
undergo frequent mitosis to replace the outer layer of cells
Cells of the basal part
cells that are highly resistant to abrasion and water diffusion
Cornified
Epidermal layers (bottom to top_
- Stratum Basale
- Stratum spinosum
- Stratum granulosum
- Stratum lucidum
- Stratum corneum
Also known as stratum germinativum. The cells that undergo constant cell division
Lies closest to epidermis.
Stratum Basale
What does Stratum Basale contains?
- One layer of cuboidal stem cells.
receive adequate nourishment through diffusion of nutrients from the dermis.
Cuboidal stem cells
found right above the stratum basale and is about 8-10 cell layer thick
Stratum spinosum
Two changes observed in the cells of Stratum Spinosum
- Conversio of cuboidal cells into keratinocytes
- Presence of many desmosomes that adjoin adjacent cells.
Why is it termed “Spinosum”
cellular projections make the cells in this layer appear spined
is found right above the stratum spinosum and is about 3-5 cell layer thick.
- cells in this layer assume the flattened appearance
Stratum Granulosum
What does Cells in Stratum Granulosum
- Start to produce keratin and keratohyalin
the proteins that cause the grainy appearance of cells in this layer
- forms the outermost skin layer, naiils and hairs
keratin and keratohyalin
is found right above the stratum granulosum in areas of the body that are constantly exposed to pressure, such as the palm, soles, and digits
- Cells in this layer are dead and flattened
- Not found everywhere
Stratum Lucidum
a protein derived
from keratohyalin.
rich in lipids which makes the layer lucid (transparent) and water resistant
Eleidin
It is a thick layer, with around 15-30 cell layers.
This entire layer is constantly shedding and is replaced with a completely new layer every 4 weeks.
Stratum Corneum
Stratum corneum’s property confers this later the ability of:
- the ability to protect the deeper layers
from abrasion, dehydration, and microbial infection.
which is found directly below the epidermal layer, is made up of dense connective tissue layer.
Dermis
What does dermis contains?
- blood vessels
- collagenous fibers
- nerves
- pigment cells
- fat cells
- fibroblasts.
Function of Dermis
- Provide support
- Cushion
- Nourishment of the epidermis
Regions of Dermis
- Papillary layer
- Reticular layer
is the upper dermal region. It is uneven and
has fingerlike projections from its superior surface, the dermal papillae, which indent the epidermis above.
Papillary layer
Receptors found in papillary layer
- Nociceptors
- Meissner’s corpuscles
What does the ventral side in hands and feet of papillae form?
Loop and whorled ridges that increase friction and enhancen gripping ability
Are genetically determined
Papillary patterns
It is the deepest skin layer that contains blood vessels, sweat and oil glands, and deep pressure receptors (Pacinian corpuscles).
Reticular layer
Examples of Accesory structures of the skin
- glands
- scales
- hairs
- nails
- claws and feathers etc.
are found in the skin, which secrete various
products
Glands
Types of glands
a. Sebaceous Glands
b. Sweat Glands
c. Ceruminous Glands
d. Mammary glands
e. Uropygial Glands
f. Mucous Glands
are usually connected to hair follicles. They secrete sebum, an oily fluid made up of fats, cholesterol, proteins, salts, and cell debris.
Sebaceous Glands
What does sebum do?
- Moistens hair
- Waterproofs skin
also known as
sudoriferous glands, are simple, coiled, tubular glands that secrete watery fluid we commonly know as sweat
Sweat Glands
2 Types of sweat glands
- Eccrine Sweat Glands
- Apocrine Sweat Glands
release sweat by merocrine secretion, i.e., the secretory products leave the cell via exocytosis.
Eccrine sweat glands
What does Eccrine produce?
Diluted sweat, which is mostly water with a few salts
release their secretory products by budding off the apical layer of the cell.
- found in the arm pits and near the genitals
Apocrine sweat glands
are found in the outer ear. They secrete cerumen or earwax. Together with the hair, it traps foreign objects that might enter into the canal.
Ceruminous Glands
Why does Ceruminous glands seep out wax?
To keep tympanoc membrane, soft, pliable and waterproof
only in mammals and are functional only in the females.
- They produce milk, a watery mixture of fats, carbohydrates, and proteins via apocrine secretion.
Mammary Glands
a certain disorder results to the formation of multiple nipples in humans along the ventrolateral axi
Polymastia
also known as preen glands, are found only in birds, and are located at the base of the tail behind the pygostyle
Uropygial Glands
are found mostly in amphibians and serve various functions from water and temperature regulation to reproduction
Mucous Glands
is formed by division of the well nourished germinal epithelial cells in the hair bulb at the inferior end of the follicle
Hairs
Parts of Hair
- Follicle
- Papilla
- Sebaceous Gland
- Hair shaft
the hair canal
Follicle
the organ that feeds hair growth
Papilla
structure which has hardened - keratinized
Hair Shaft
types of hair (produced by follicle)
a. Lanugo
b. Vellus hair
c. Terminal Hair
the fine hair that covers nearly the entire body of embryos
Lanugo
the short, fine, “peach fuzz” body hair that grows in most places on the human body in both sexes
Vellus Hair
the fully developed hair, which is generally longer, coarser, thicker, and darker than vellus hair.
Terminal Hair
is a scale like modification of the epidermis that corresponds to the hoof or claw of other animals
Nails
is responsible for
nail growth
Nail matrix (The Thickened proximal area)
- Serves as an important recognition mark or warning coloration
- Subdued or crytpic when used for comoflouge
Structures for Coloration
Animal coloration may due to
- Structural coloration
- Pigmentation
certain colors are produced by the physical structure of the surface tissue, which reflects certain light wavelengths and eliminates others
Structural Color
The more common means of coloration is through the use pigments.
Pigmentation
Know animal pigments
- Melanin
- Carotenoids
a group of black or brown polymers responsible for various earth colored shades that most animals wear
Melanins
yellow and red colors which are frequently contained within special pigment cells (xanthophores)
Carotenoids
excessive consumption of carrots
- condition where beta- carotene levels in the blood goes up and changes the color of the skin to orange.
Carotenemia
