7 Animal Integument Flashcards
The system that covers the outer of the animal body, including the skin and structures derived from it, such as hair, feathers, setae, and horns.
integumentary system
What are the functions of the integumentary system? (4)
- Protective wrapping
- Regulatory and Excretory functions
- Sensory Functions
- Behavioral interactions between individuals
What are the functions of the integumentary system’s protective wrapping? (4)
- mechanical protection
- a barrier against bacteria
- prevents fluid loss or gain; and
- protects underlying cells from UV radiation.
What are the functions of the integumentary system’s regulatory and excretory functions?
Osmo- and Thermoregulation , due to the presence of sweat glands and other structures.
What sensory functions are associated with the integumentary system? (4)
- thermoreceptor (senses heat/cold)
- Meissner’s corpuscles (senses touch)
- nociceptor (senses pain)
- Pacinian corpuscle (sense pressure)
What affects how individuals interact, and in some animals, such as snakes, coloration can signal whether they are venomous.
Pigmentation
Many protozoans have only a delicate cell or plasma membrane for __. __ functions for gas exchange, waste removal by simple diffusion, and uptake of dissolved nutrients.
- external covering
- Protozoan integument
What is the thick protein coat in some protozoans that provides environmental protection and transmits the force of cilia or flagella during movement? Give an example of organism that have this.
- Pellicle
- Ex.: Paramecium
What is the epidermis in multicellular invertebrates made of?
a single layer of columnar epithelial cells
Some invertebrates add a __ over the epidermis for additional protection. Give an example of organism that have this.
- noncellular cuticle
- Ex.: Nematodes
The molluscan epidermis is delicate, contains __, and secretes __ for the shell.
- mucous glands
- calcium carbonate
Compared to lower invertebrates, mollusks have a more complex integument consisting: (5)
- cuticle
- simple epidermis
- connective tissue
- iridocytes (reflecting cells)
- thicker connective tissue layer
The arthropod integument is the most complex of integument because their integument can perform __, with a hardened cuticle that serves as an __. Depending on the taxon of arthropod, the means of hardening could be one of the following processes that act on the __.
- skeletal functions
- exoskeleton
- procuticle layer
How is the arthropod cuticle hardened? (2)
- calcification (deposition of calcium carbonate, as in crustaceans)
- sclerotization (cross-linking of protein molecules, as in insects).
deposition of calcium carbonate, as in crustaceans
calcification
protein molecules bond together with stabilizing cross-linkages within and between adjacent lamellae of the procuticle. This protein is tough, highly resistance, and water insoluble. Observed in insects.
sclerotization
__ is a tough, highly resistant, and water-insoluble protein found in the __ of insects. It bonds together with stabilizing cross-linkages within and between adjacent __, contributing to the hardening of the exoskeleton in a process called sclerotization. This process strengthens the insect’s exoskeleton, making it more durable and protective.
- sclerotin
- procuticle
- lamellae
Why must arthropods molt or shed their exoskeleton?
their exoskeleton cannot grow with the animal, so they must shed it to accommodate growth.
The process by which arthropods shed their exoskeleton to accommodate growth. Since their exoskeleton cannot expand, molting allows the animal to grow a new, larger exoskeleton. This process is crucial for their development, but it temporarily leaves them vulnerable until the new exoskeleton hardens.
molting (ecdysis)
What are the steps involved in arthropod molting (ecdysis)? (5)
1) epidermal cells divide by mitosis
2) secretion of enzymes to digest the procuticle
3) absorption of digested material
4) formation of new epicuticle and procuticle; and
5) hardening of the new cuticle by calcification or sclerotization.
The vertebrate integument is the __ and its __.
- skin
- derivatives
What are the two main layers of vertebrate skin?
- epidermis
- dermis
is not part of the skin; it is a layer of loose connective tissue, adipose tissue, and nerve endings that separates the skin from deeper tissues.
hypodermis
- made up of stratified keratinized squamous epithelium.
- It is devoid of blood vessels, i.e., it is avascular.
- Cells of the basal part undergo frequent mitosis to replace the outer layer of cells.
- New generations of cells undergo keratinization, which make the cells
cornified—cells that are highly resistant to abrasion and water diffusion
Epidermis
What type of tissue makes up the epidermis?
stratified keratinized squamous epithelium
Epidermis have new generations of cells undergo __, which make the cells __—cells that are highly resistant to abrasion and water diffusion
- keratinization
- cornified
The epidermis is __, meaning it has no blood vessels.
avascular
What are the layers of epidermis? (5)
- Stratum corneum
- Stratum lucidum
- Stratum granulosum
- Stratum spinosum
- Stratum basale
- the deepest cell layer of the epidermis, located closest to the dermis.
- contains only one layer of cuboidal stem cells that receive adequate nourishment through diffusion of nutrients from the dermis.
- The cells constantly undergo cell division, and millions of new cells are produced daily. The daughter cells are pushed upward, away from the source of nutrition, to become part of the epidermal layers closer to the skin surface.
stratum basale or stratum germinativum
The stratum basale contains a single layer of __ that undergo cell division to produce new cells that move toward the skin surface.
- cuboidal stem cells
Cells in the stratum basale receive nourishment through __ of nutrients from the __.
- diffusion
- dermis
- a layer in epidermis found right above the stratum basale and is about 8-10 cell layer thick.
- ## Cells from the stratum basale migrate to this layer to undergo important changes as they continue to go upward.
Stratum spinosum
The stratum spinosum is located above the __ and is about __ cell layers thick.
- stratum basale
- 8-10
Two of the changes observed in the cells found in the stratum spinosum (2)
- conversion of the cuboidal cells into keratinocytes
- presence of many desmosomes that adjoin adjacent cells.
In the stratum spinosum, cuboidal cells convert to __ and develop numerous __, giving them a spined appearance, hence the name “spinosum”.
- keratinocytes
- desmosomes
join adjacent cells, providing strength and creating the spined appearance of cells in the stratum spinosum.
desmosomes
- a layer in the epidermis located above the stratum spinosum and is about 3-5 cell layers thick.
- Cells in this layer assume the flattened appearance. Cells also start to produce keratin and keratohyalin, the proteins that cause the grainy appearance of cells in this layer.
- Cells in this layer start to die, i.e., they start to lose their nuclei and other organelles. What remain in the cells in this layer are the keratin and keratohyalin, which will form the outermost skin layer, nails, and hairs.
Stratum granulosum
The stratum granulosum is located above the __ and is about __ cell layers thick.
- stratum spinosum
- 3-5
Cells in the stratum granulosum become flattened and grainy due to the production of __ and __ proteins. These proteins contribute to forming the outermost skin layer, nails, and hair.
- keratin
- keratohyalin
Cells in the stratum granulosum begin to die, losing their __ and __, while keratin and keratohyalin remain.
- nuclei
- organelles
- a layer of epidermis located above the stratum granulosum and is found in areas constantly exposed to pressure, such as the palms, soles, and digits.
- contains eleidin, a lipid-rich protein derived from keratohyalin, which gives the layer a transparent (lucid) and water-resistant quality.
Stratum lucidum
The stratum lucidum is located above the __ and is found in areas constantly exposed to pressure, such as the palms, soles, and digits.
stratum granulosum
The stratum lucidum contains __, a lipid-rich protein derived from keratohyalin, which gives the layer a transparent (lucid) and water-resistant quality.
eleidin
- a layer of epidermis: In thick skin, it is located above the stratum lucidum; in thin skin, it is located above the stratum granulosum.
- around 15-30 cell layers thick, and its cells are dead, flattened, and cornified, providing protection.
- protects deeper layers from abrasion, dehydration, and microbial infection.
- completely replaced every 4 weeks as it constantly sheds.
Stratum corneum
In thick skin, the stratum corneum is above the __; in thin skin, it is located above the __.
- stratum lucidum
- stratum granulosum
The stratum corneum is around __ cell layers thick, and its cells are dead, flattened, and cornified, providing protection.
15-30
The stratum corneum protects deeper layers from (3)
- abrasion
- dehydration
- microbial infection
- located directly below the epidermis and is composed of dense connective tissue.
- contains blood vessels, collagenous fibers, nerves, pigment cells, fat cells, and fibroblasts.
- provides support, cushioning, and nourishment to the epidermis.
Dermis
The dermis is located directly below the __ and is composed of __.
- epidermis
- dense connective tissue
The dermis contains: (6)
- blood vessels
- collagenous fibers
- nerves
- pigment cells
- fat cells
- fibroblasts
The two regions of the dermis are: (2)
- papillary layer
- reticular layer
The __ is the upper dermal region, and it has fingerlike projections called dermal papillae that indent the epidermis above.
papillary layer
The __ contain capillary loops that provide nutrients to the epidermis and receptors like nociceptors and Meissner’s corpuscles for pain and touch.
Dermal papillae
Sensory receptors found in dermal papillae (2)
- nociceptors (pain)
- Meissner’s corpuscles (touch)
On the ventral side of the hands and feet, __ form looped and whorled ridges that increase friction for gripping and create unique fingerprints. Fingerprint patterns are genetically determined, and no two individuals have the same fingerprint pattern.
dermal papillae
The __ is the deepest layer of the skin, containing blood vessels, sweat and oil glands, and deep pressure receptors (Pacinian corpuscles). It contains phagocytes, which prevent bacteria that have passed through the epidermis from penetrating deeper into the body.
reticular layer
Sensory receptor found in the reticular layer of dermis
Pacinian corpuscles (pressure receptors)
The reticular layer contains __, which prevent bacteria that have passed through the epidermis from penetrating deeper into the body.
phagocytes
What are the accessory structures of the skin? (6)
- glands
- scales
- hairs
- nails
- claws
- feathers
What are the origins of accessory structures of the skin? Give an example each (2)
- epidermis (e.g., talons)
- dermis (e.g., carapace).
What are the glands in accessory structures of the skin? (6+2 subtypes)
A. sebaceous glands
B. sweat glands (sudoriferous glands)
- Eccrine sweat glands
- Apocrine sweat glands
C. Ceruminous glands
D. Mammary glands
E. Uropygial glands
F. Mucous glands
The skin primarily contains __ glands, which have ducts that drain secretions to the outside of the body.
exocrine
__ glands are connected to hair follicles and secrete sebum, an oily fluid an oily fluid made up of fats, cholesterol, proteins, salts, and cell debris that moistens hair and waterproofs the skin.
Sebaceous
What is sebum composed of? (5)
- fats
- cholesterol
- proteins
- salts
- cell debris
Glands are named according to their __.
secretory products
are coiled tubular glands that secrete sweat.
Sweat glands or sudoriferous glands
What are the two types of sweat glands? (2)
- eccrine
- apocrine
__ sweat glands release sweat by merocrine secretion, where secretions leave the cell via exocytosis without damaging the cell. This gland produces diluted sweat, which is mostly water with a few salts.
Eccrine
Eccrine sweat glands release sweat by __, where secretions leave the cell via exocytosis without damaging the cell. This gland produces __, which is mostly __ with a few __.
- merocrine secretion
- diluted sweat
- water
- salts
- Cells of the __ sweat glands release their secretory products by budding off the apical layer of the cell.
- This type of sweat glands are found in the __ and near the __.
- Their secretion is rich in organic matter. It is usually odorless but skin microflora can easily break it down and cause body odor.
- apocrine
- arm pits
- genitals
Apocrine sweat is usually odorless, but skin microflora break it down, leading to __.
body odor
- a gland located in the outer ear and secrete cerumen, or earwax. Together with the hair, it traps foreign objects that might enter into the canal.
- also seep out wax to keep the tympanic membrane (eardrum) soft, pliable, and waterproof.
Ceruminous Glands
Cerumen traps foreign objects, keeps the __ soft, pliable, and waterproof, and prevents debris from entering the ear canal.
tympanic membrane
- a gland found only in mammals and are functional only in females, where they produce milk, a watery mixture of fats, carbohydrates, and proteins via apocrine secretion. With this reason some scientists hold that this gland is a modified __.
- mammary gland
- apocrine sweat glands
Mammary glands produce milk via __, which is a mixture of __, __, and __.
- apocrine secretion
- fats
- carbohydrates
- proteins
- Mammary glands develop on both sexes from __, a pair of elevated ribbons of ectoderm that extend along the ventrolateral body wall of the fetus from axilla to groin. In the example, the these are numbered from __ to __.
- This can differentiate into mammary glands, and their presence along the ventrolateral part of the fetus explain why some mammals have multiple breasts.
- milk lines
- MB1
- MB5
In mammals, the distribution of nipples varies by species:
- canines, cats, rodents, and edentates have __, __, __, and __ nipples;
- primates have __ nipples; and
- cetaceans have __ nipples.
- axillary, thoracic, abdominal, inguinal
- thoracic
- axillary
a condition where extra nipples form along the ventrolateral axis. Harry Styles has four nipples as an example of this condition.
polymastia
- glands located at the base of the tail behind the pygostyle in birds.
- secrete a fluid rich in lipids and proteins that birds spread on their feathers during preening, making them water-repellent.
Uropygial glands (preen glands)
- Uropygial glands are located at the base of the tail behind the __ in birds.
- Uropygial glands secrete a fluid rich in lipids and proteins that birds spread on their feathers during __, making them __.
- pygostyle
- preening
- water-repellent
This gland is mostly found in amphibians and serve various functions, including water regulation, temperature control, and aiding in reproduction. In some frogs, males have swollen __ in their palms that help them grip females during copulation.
Mucous Glands
- serves as an epidermal outgrowth that provides protection.
- formed by the division of germinal epithelial cells in the hair bulb at the follicle’s inferior end, and as cells are pushed up, they become keratinized and die.
Hair
Hair is formed by the division of __ cells in the hair bulb at the follicle’s inferior end, and as cells are pushed up, they become __ and die.
- germinal epithelial
- keratinized
The four main parts are the __ (canal), __ (feeds hair growth), __ (oil gland), and __(keratinized structure).
- follicle
- papilla
- sebaceous gland
- hair shaft
What are the three types of hair produced by follicles?
- Lanugo
- Vellus hair
- Terminal hair
Type of hair produced by follicles: fine hair covering embryos.
Lanugo
Type of hair produced by follicles: short, fine “peach fuzz” found on most of the body.
vellus hair
Type of hair produced by follicles: longer, coarser, thicker hair found on the scalp, eyebrows, and specific body regions like underarms and pubic area.
terminal hair
a scale-like modification of the epidermis that corresponds to the hoof or claw of other animals.
nail
The main parts of a nail include the __ (unattached), the __ (visible attached portion), and the __ (embedded in the skin).
- free edge
- nail body
- nail root
are skin overlaps at the nail’s borders, and the thick proximal of this is called the cuticle.
nail fold
The __, part of the stratum germinativum, lies beneath the nail, while the __, the thickened proximal area, is responsible for nail growth.
- nail bed
- nail matrix
Vivid colors often serve as __ or __(e.g., bright colors indicate poison), while subdued colors are used for __.
- recognition marks
- warning coloration
- camouflage
Animal coloration can be due to __ or __.
- structural coloration
- pigmentation
- __ is produced by the physical structure of surface tissues that reflect certain light wavelengths while eliminating others, especially seen in birds.
- Certain structural colors in feathers are caused by minute, air-filled __ or __ that reflect white light or specific portions of the light spectrum.
- Structural coloration
- spaces
- pores
__(__) are varied molecules that reflect light rays; they are a common means of coloration in animals.
Pigments (biochromes)
The main animal pigments include __ (black/brown polymers for earth-colored shades) and __ (yellow/red colors).
- melanins
- carotenoids
Most vertebrates cannot synthesize __ pigments and must obtain them directly or indirectly from plants. Excessive carrot consumption can lead to __, which increases beta-carotene levels in the blood, changing the skin color to orange.
- carotenoid
- carotenemia
