Exam 2 Flashcards
What are the 4 types of tissues
Epithelial, connective, muscle, and nervous
What are tissues
Cells of similar type and function clustered together
What is epithelial tissue
Sheets of cells that cover and line other tissues
What is connective tissue
They provide support and structure to membranes
What is muscle tissue
Tissue that enables movements
What is nervous tissue
Tissue that directs work
What tissue types are found in most organs
All of them
What is histology
Study of microscopic tissue and organs
What are the functions of epithelial tissue
Protection, filters biochemical substances, absorbs nutrients, provides sensory input, manufactures secretions, and manufactures exretions
What are the important characteristics of epithelia tissue
Each cell is polar, has a lateral surface containing junctional complexes that connect each cell to its neighboring cells, avascular, and innervated
What is the apical surface
The top surface of the cell that faces the lumen
What is the basal surface
The bottom surface that faces underlying connective tissue
What are the functions of the basal lamina
Foundation of the epithelial cells, there is a nonliving network of fibers that cement cells to underlying tissue varying in thickness secreted by epithelial cells, helps prevent cells from being torn off by either stretching or rubbing, and a partial barrier to underlying tissue that allows passage of oxygen and nutrient from capillaries and removes epithelial waste
What are the different cellular attachments
Tight junctions, desmosomes, gap junctions, and basement membrane
What are tight junctions
Formed by fusion of the outermost layers of plasma membranes of adjoining cells allowing for no leaks, wraps around the cell like a belt making a seamless barrier, and are found in the urinary bladder and digestive tract
What are desmosomes
Connects plasma membranes of adjacent cells but does not seal them, they are strong mechanical coupling plaques locked by tonofilaments similar to velcro, and found in tissues that undergo repeated tension/stretching such as the skin, heart, and uterus
What are gap junctions
Connexons a protein that links cells by a tubular channel as an extension from the cytoplasm of one cell to the next allowing an exchange and passage of ions and nutrients to quickly transport electrical signals btw cells
How are hemidesmosomes specified
Their connection to basement membrane
What type of cells are gap junctions present
Cardiac and smooth
How do surface specialization vary
Depending on their location on their role in the function of the tissue
What are the functions of microvilli
Increases surface area for absorption, forms a brush border, and contains cilia
What is cilia
Hair like microvilli that can beat in unasyn to transport material
What is keratin
Protective waterproof substance
What are the different methods of classification for epithelia
Number of layers of cells, shape of cells, and presence of surface specialization
What are simple squamous epithelium
Delicate and thin cells that reduce friction so they are found in the lining surfaces involved in passage of either gas or liquid
What is the mesothelium
Lines the pleural, pericardial, and peritoneal cavities
What is the endothelium
Lines the blood and lymphatic vessels
What are simple cuboidal epithelium
Single layer of cube shaped cells w/ the nuclei aligned in a single row found in areas where secretion and absorption occur such as the surface of ovaries, secretory glands, and lining of ducts
What are simple columnar epithelium
Elongated closely packed together making a more protective layer w/ nuclei aligned in a row at the base of the cell they are associated w/ absorption and secretion commonly found in excretory ducts, the digestive tract, oviducts, and resp tract
What are specific simple columnar epithelium found in the GIT
Absorptive cells that are covered in microvilli and goblet cells that secrete mucus
What are stratified squamous epithelium
Multilayered epithelium that protects the underlying tissues, the outer layers continually being worn away, and occurs in areas of body subject to mechanical and chemical stresses such as the mouth, esophagus, and vagina
What type of cells do stratified squamous epithelium originate as
Cuboidal cells at the base layer
What are stratified cuboidal epithelium
Generally occurs in two layers, protects underlying tissues, and is found primarily along large excretory ducts such as sweat glands, mammary glands, and salivary glands
What are stratified columnar epithelium
Rare cells in selected parts of the mammary gland and urethra for secretion and protection
What is pseudostratified columnar epithelium
A non stratified layer of cells w/ nuclei at varying levels, most cells are ciliated, the cells reach the luminal surface of the basement membrane, and are found in the trachea and portions of the male reproductive tract
What is transitional epithelium
Basal layer of cuboidal or columnar cells with a superficial layer of squamous cells, they are leak proof membrane, and are found in regions required to expand and contract as part of their normal function such as the ureters, urethra, and bladder
What are glands
Cell or group of cells that manufacture and discharge a secretion classified by the presence or absence of ducts, number of cells that compose them, shape of secreting ducts, complexity of glandular structure, type of secretion produced, and manner in which secretion is stored and discharged
What are endocrine glands
Have no ducts or tubules, produce and secrete hormones directly into bloodstream or lymphatic system such as the pituitary, adrenal glands, and pancreas
What are exocrine glands
Possess ducts, discharge secretions directly into local areas by ducts except for goblet cells, and unicellular/multicellular such as hepatoid, musk, sweat, salivary, liver, and pancreas glands
What are unicellular exocrine gland
Only example is the ductless goblet cell composed of modified columnar epithelia and secretes mucin found among columnar cells of respiratory, GIT, and conjunctiva of the cells
What are multicellular exocrine glands
Composed of a secretory unit and a duct, the secretory unit is usually surrounded by CT is rich in blood vessels, nerve fibers, and may be surrounded by myoepithelial cells, and the rate of secretion production is controlled by hormones and nervous influences
What are the 2 ways exocrine glands can be catorgerized by complexity
Simple (unbranched) and compound (branched)
What are the 3 ways to classify exocrine glands by shape
Tubular, alveolar, and tubuloalveolar
What are tubular exocrine glands
Evenly long and wide channels typically such as intestinal glands
What are alveolar exocrine glands
Aka acinar they are rounded sacs such as sebaceous glands
What are tubuloaveolar exocrine glands
aka tubuloacinar they are both tubular and alveolar qualitiies and are found in mammary glands
What are the 3 classifications of exocrine glands by secretion style
Merocrine, apocrine, and holocrine
What are merocrine exocrine glands
Secretory cells remain intact, packaged, and released via exocytosis as manufactured
What are apocrine exocrine glands
Glands store their secretions w/in themselves and the top part of cell is released into the duct system
What are holocrine exocrine glands
Glands store their secretions w/in themselves and the entire cell is destroyed in the act of releasing its product
What are the 2 classifications of exocrine glands by secretion
Serous which is watery and high concentration of enzymes and mucous which is thick/viscous composed of glycoproteins
What are mixed exocrine glands
Both serous and mucous components
What are the functions of CT
Metabolic and structural connections btw other tissues, protective sheath around organs, insulation for the body, reserve for energy, framework to support the body, medium for transporting substances from one region of the body to another, and playing a role in the healing process/control of invading microorgansim
What are the general characteristics of CT
Most abundant tissue by weight, vascularized, made of ground substance, EC fibers, and cells
What is ground substance
How cells exchange nutrients and waste w/ blood, amorphous (gel like) homogeneous material, envelopes and protects delicate cells, effective obstacle for invading microorgansims, and contains GAGs
What is the major component of ground substances
Hyaluronic acid
What are EC collagenous fibers
Strong thick strands of protein collagen, organized into bundles, and vary in density and arrangement of fibers such as surrounding organs and tendons/ligaments
What are EC reticular fibers
Thin, delicate, branched networks of collagen that provide support for highly cellular organs found in endocrine glands, lymph nodes, spleen, bone marrow, liver, nerves, blood vessels, muscle fibers, and capillaries
What are EC elastic fibers
Composed primarily of elastin protein, branched to form complex networks, and occur in tissues subjected to stretching such as the vocal cords, lungs, skin, and walls of blood vessels
What are the three types of EC fibers CT is composed of
Collagenous, reticular, and elastin
What are the 2 types of cells CT is composed of
Fixed cells and wandering/transient cells
What are fixed cells
Remains in CT and is involved in production/maintenance of the matrix in specific tissues such as fibroblast, chondroblast, osteoblast, adipocyte, and reticular cell
What are wandering cells
Passes in and out of CT and involved in repair/protection of tissue such as leukocyte, mast cells, and macrophage
What are the 2 types of connective CT
Connective tissue proper and specialized connective tissue
What are the 2 different types of connective tissue proper
Loose connective tissue and dense connective tissue
What are the 3 type of loose connective tissue
Areolar, adipose, and reticular
What are the 3 types of dense connective tissue
Dense regular tissue, dense irregular tissue, and elastic tissue
What is areolar tissue
Loose CT, tangle of random fibers and cells suspended in thick ground substance, predominant cell is fibroblast, pathological state allows the spaces to fill w/ fluid, and the functions are surrounds/supports, provides nutrients, and present in all mucous membranes
What is CT proper adipose tissue
Loose CT, areolar tissue in which adipocytes predominate, located throughout the body, highly vascular, 2 types white and brown, functions include energy storehouse, thermal insulator, and mechanical shock absorber
What is CT proper reticular tissue
Loose CT containing only reticular fibers that are thin loosely arranged reticular fibers/fibroblasts suspended in ground substance forming the framework of organs called stroma found in spleen, lymph nodes, bone marrow
What do all types of dense fibrous CT have in common
The are densely packed collagen fibers
What are dense regular CT
Tightly packed parallel collagen fibers, fibroblasts form rows, relatively avascular, and found in tendons, ligaments, and fascia
What are dense irregular CT
Thicker bundles of collagen than regular, fibers interwoven into single sheets, recieves signals from the epithelial, and are found on the dermis, fibrous covering of the kidney, testes, liver, and spleen, and forms the tough capsule of joints
What are elastic CT
Composed primarily of elastic fibers that are either parallel or interwoven w/ fibroblasts and collagen found in the spaces btw vertebrae, walls of arteries, stomach, bronchi, bladder, heart, and nuchal ligament in horses
What is the nuchal ligament
Continuation of the elastic tissue in the vertebae that runs from the top of the withers to the back of the skull around C1&C2 reducing the strain when the horse is grazing for a long period of time or while running
What are the 3 types of specialized CT
Cartilage, bone, and blood
What are the 3 types of specialized CT cartilage
Hyaline, elastic, and fibrocartilage
What is cartilage
More rigid than dense CT but more flexible than bone, avascular, enclosed w/in a perichondrium, contains chondrocytes in lacunae, matrix contains ground substance, tissue fluid, collagen, and elastic fibers, and found in joints, ears, nose, vocal cords, and framework for bone formation
What is the perichondrium
Nutrient and waste exchange point for cartilage
What is hyaline cartilage
Most common cartilage, most rigid cartilage composed of closely packed collagen fibers, and found in most embryonic skeleton, tracheal rings, auricular cartilage, growth plates of long bones, and sternum to ribs connections
What is elastic cartilage
Contains many elastic fibers in dense branching bundles, flexible for repeated bending, and located in the epiglottis of the larynx and the external ears of animals
What is fibrocartilage
Usually found merged w/ hyaline cartilage and dense CT containing thick bundles of hyaline cartilage, has no perichondrium, designed to take compression, and is located btw vertebrae of spine (discs), btw bones in pelvis, and meniscus of the knee joint
What is blood
Matrix consists of plasma as a ground substance, proteins as fibrous components, and cells are erythrocytes, leukocytes, and thrombocytes
What is a membrane
Thin protective layers of epithelial sheet bound to underlying CT proper
What are the 4 common types of membranes
Mucous, serous, cutaneous, and synovial
What are mucus membranes
Lines organs w/ connections to outside environment such as the mouth, GIT, trachea, sinuses, bladder, and uterus, composed of stratified squamous or simple columnar epithelium covering the lamina propria, secretes large quantities of mucus, and can absorb in the intestine
What contains the mucous to the underlying layers
Submucosa
What does mucus contain
Water, electrolytes, and mucin
What are serous membranes
Single sheet of simple squamous epithelium bound to underlying layer of loose CT and produces thin watery serosal fluid in the pleura, peritoneum, and pericardium
What do the parietal and visceral layers of the peritoneum merge to form
Mesenteries in the abdominopelvic cavity such as the omentum
What is serosal fluid
Small amounts normally found in body cavities excessive fluid w/in body cavity is known as effusion and abnormally low amounts of serosa produced leads to adhesions
What are adhesions
Abnormal serosal attachments w/in body cavity similar to scar tissue
What is hemoabdomen and hemothorax
Excessive blood in the abdomen and thorax
What is chyle effusion
Excessive lymphocytes in the thoracic cavity
What are cutaneous membranes
Integument epidermis that is always exposed to outside environment make of keratinized stratified squamous epithelium and is attached to an underlying layer of dense irregular CT
What are synovial membranes
Lines the cavities of joints made of CT and adipose tissue covered by a layer of collagen fibers, contains no epithelium, and fibroblasts and is manufacture synovial fluid that fills joint spaces
What is muscle tissue
Fibrous cells designed for contraction composed of actin and myosin that slide over one another
What is skeletal muscle
Large cells containing hundreds of nuclei and mitochondria, striated, collagen fibers surrounding cells merge w/ collagen fibers in tendons to attach muscle to bone, voluntary, and become paretic or paralyzed
What is smooth muscle
Small spindle shaped cells, non striated, involuntary, found in walls of hollow organs such as blood vessels, urinary bladder, uterus, intestines, stomach, and exocrine glands, and is responsible for peristalsis
What is cardiac muscle
Located in the heart they are small branching cells w/ only one nucleus, striated, connected via intercalated disks, contains specialized pacemaker cells to signal contractions at regular intervals, and involuntary
What is nervous tissue
Designed to receive and transmit signals throughout the body, located in the brain spinal cord, and peripheral nerves, and consists of neurons and neuroglial cells
What is longest cells in the body
Neurons
What are the 3 primary parts of neurons
Perikaryon (cell body), dendrites, and axon
What neuroglial cells
Support neurons, do not transmit impulses, have insulating conductive membranes, provide framework, supply nutrients, and has phagocytizing properites
What are the 3 healing and repairing steps
Inflammation, organization, and regeneration
What is the inflammation step
Vasoconstriction in the initial 5-10 mins to control hemorrhage followed by a sustained period of vasodilation to surrounding capillaries to increase blood flow to affected area, fluid pours to affected area causing swelling, pain, and tenderness, clot formation slows bleeding and isolates wound to prevent spread of pathogens to body this is where fibrinogen is converted to fibrin, phagocytosis thru macrophages and neutrophils, and heparin and histamine are dispersed by the increased blood flow decreasing further swelling
What trigger vasodilation
Heparin and histamine
What is the organization stage
The formation of granulation tissue allows for wound repair which consists of phagocytosis and the granulation tissue allows for collagen fibers and newly branched capillaries and resistant to infection
What is proud flesh
When horses grow too much granulation tissue develops
What is the regeneration/fibrosis step
Epithelialization covers granulation tissue, the scab is pushed off, granulation tissue becomes fibrous scar and the contraction pulls wound close, and adhesions may occur in the thoracic or abdominal cavities
What are the classifications of wound healing
First intention and second intention
What is first intention
Wound edges in close apposition, no granulation tissue formation, no scarring, and surgical repair
What is second intention
Wound edges separated from each other, scarring results, and granulation occurs
What is the function of the integumentary system
Covers/protects, prevents desiccation, reduces threat of injury, assists in maintenance of normal body temp, excretes water, salt, and organic waste, receives and conveys sensory info, synthesizes vitamin D, and stores nutrients
What is the epidermis
The surface of the skin
What is the hypodermis
Thick layer that resides below the dermis, allows skin to move freely over underlying structures, and contains loose layer of areolar tissue has fibers continuous w/ dermis, adipose, blood, and lymphatic vessels, nerves, and pacinian corpuscles
What is a keratinocyte
Specialized squamous epithelial cell that produces keratin giving the skin resiliency, waterproof, and strength
What is keratinization
Development/growth of new keratin cells allows cells to exfoliate daily
What are melanocytes
Cells that are located in the deepest epidermal layer that produce melanin and provides UV protection
What is melanin
Pigment stored in melanosomes which are later absorbed by keratinocytes
What are langerhans cells
Epidermis specific macrophages that phagocytize micro invaders
What are merkel cells
Located at the epidermal junctions associated w/ sensory nerve endings to form the merkel disc
What are the 5 layers of the epidermis from deepest to superficial
Stratum germinativum, stratum spinosum, stratum granulosum, stratum lucidum, and stratum corneum
What are the 3 epidermal layers for hairy skin
Stratum basale, stratum spinosum, and stratum corneum
What are tactile elevations
Epidermal papillaes hold tactile hairs (tylotrich hairs) which gives the animal a perception of touch
What is the dermis
The greatest portion of integument, animals hide made of highly fibrous dense irregular CT, and has 2 layers that papillary layer and reticular layer
What are other components of the dermis
Hair follicles, nerve endings, glands, smooth muscle, blood vessels, lymphatic channels, fibroblasts, adipocytes, and macrophages
What is the papillary layer
The top layer of the dermis that contains the dermal papillae, blood vessels, and nerve endings
What is dermal papillae
Increase surface area to cement epidermis to dermis
What is meissner’s corpuscles
A nerve that creates sensitivity to light touch
What is the reticular layer
Consist of 80% of the dermis, indistinct boundary btw papillary layer, and parallel bundles of collagen fibers that make up tension lines and dermal folds or flexure lines
What are tension lines
Separation btw bundles that determine where the skin will fold and move
What are dermal folds/flexure lines
Dermis tightly secured to underlying tissues found in regions where a lot of flexing occurs
What are pacinain corpuscles
Touch receptor sensitive to heavy pressure
What are the special features of the integument
Pigmentation, paw pads, palnum nasale, ergots, chestnuts, and cutaneous pouches in sheep
What is pigmentation
Result of dispersion of the granules, non pigmented granules are near the nucleus, is controlled by the hypophysis (pituitary gland) producing melanocyte stimulating hormone (MSH) melanosomes are absorbed by keratinocytes arranged on side of cell w/ greatest amount of sun exposure
What are the characteristics of paw pads
Tough, thick layers of fat and CT, conical papillae cover entire pad, has all 5 epidermal layers, pigmented, and there are 3 ind pads
What are the 3 foot pads
Carpal pad, metacarpal/metatarsal pads, and digital pads
What are the planum nasale
Top of the nose in cats, pigs, sheep, and dogs, usually pigmented, covered in polygonal plaque w/ deep grooves in the stratum corneum, and aglandular except in sheep, pigs. and cows
What is the planum nasolabiale
Muzzle in cows and horses
What does polygonal plaque do for the animal
Increases their sense of small
What are ergots and chestnuts
Dark horny structures on legs of equine family thought to be vestiges of digits
Where are chestnuts
Inside of each leg at carpus and tarsus thought to be vestiges of carpal/tarsal pads of 1st digit
Where are ergots
Buried in caudal hairs of fetlock thought to be vestiges of carpal/tarsal pads of 2nd and 4th digits
What are the cutaneous pouches in sheep
Infoldings of skin that contain fine hair, sebaceous, and oil glands located infraobital, interdigital, and inguinal, and they secrete lanolin, a fatty yellow substance that dries to the skin is waterproof and antibacterial
What are the related structures of the integument
Hair, arrector pili muscles, glands of the skin, claws, dewclaws, hooves, horns
What are the functions of hair
Maintenance of body temperature and protection via camouflage
What are arrector pili
Small smooth muscle that attaches to each hair follicle is innervated by sympathetic nervous system and contraction pulls the hair erect
What are sebaceous glands
Duct empties into hair follicle or directly onto skin the holocrine glands located in the dermis, they can be simple or complex alveolar structures, the excrete sebum and lanolin they are located on the lips, labia vulvae, penis, prepuce, anus, eyelid, and ear canal
What are the glands of the skin
Sebaceous glands, sweat glands, tail glands, and anal sacs
What are the 3 layers in the wall of the hair follicle
Internal epithelial root sheath, outer epithelial root sheath, and dermal/CT root sheath
What are the 3 concentric layers on the skin
Medulla that is flexible soft keratin, cortex that is rigid hard keratin, and cuticle that is a single layer in scales
What are compound follicles
Multiple hair strands in single pore 3 compound follicles group to emerge from same epidermal fold in dogs
What are the 3 phases of the hair growth cycle
Anagen growth phase, catagen transition phase, and telogen resting phase
What is telogen effluvium
The medical term for blowing coat aka shedding
What expresses hair color
Pigment in cortex and medulla of hair strand melanin produced in base of hair follicle and transferred to hair strand this decreases w/ age
What causes hair color to change
Different colors due to quantity and type of melanin such as pheomelanin for yellowish and reddish colors and tyrosine melanin for brown black colors
What are the types of hair
Primary hairs, secondary hairs, and tactile hairs
What are primary hairs
Guard hairs that stand straight or arched thicker and longer than secondary hairs and dominant hairs in complex hair follicle
What are secondary hairs
Wool type hairs that are softer and shorter than primary hairs
What is sebum
Oily lipid substance the sebum forced thru duct into hair follicle by the arrector pili muscle that contracts and compresses gland the sebum coats base of the hair and surrounding skin trapping moisture, keeps skin and hair soft, pliant waterproof, and reduces risk of infection
What are sweat glands
Sudoriferous glands produce watery transparent liquid to help cool body thru evaporation, found over entire body only horses produce profuse sweat
What are the 2 types of sweat glands
Eccrine and apocrine
What are eccrine sweat gland
Empty onto surface of skin found on foot pads of dogs
What are apocrine sweat glands
Empty into hair follicles found in external ear canal of dogs
What are tail glands
Oval region at dorsal base of tails of most dogs and cats especially large apocrine and sebaceous glands w/ coarse oily hairs they assist animals in identification of one another
What are anal sacs
Reservoir for malodorous secretions, similar to those from musk glands lined w/ sebaceous and apocrine glands, contents are expressed w/ defecation or when the animal is frightened, and located in all mammals connected by single small duct to lateral margin of anus and can become infected
What are claws
Hard outer coverings of distal digits that are non retractable except in most cats functions include maintaining traction, defense, and catching prey
What are dewclaws
Evolutionary remnants of digits the first digit in dogs and cats and second and fifth digits in cows, pigs, and sheep
What is the hoof
Horny outer covering of digits of ungulates each hoof covers a digit, not all hooves are weight bearing, made of modified epithelial layer, and rests on the corium
What is the corium
Tissue the hoof rests on that is a modified dermis attached to the periosteum of P3 it is innervated and sensitive to pain
What are the parts of the wall of the horse hoof
It is convex and broken into the toe, quarters, and heel
What is the sole of the equine hoof
The plantar or palmar surface contains the white line which is the junction of the sole and hoof wall
What is the frog of the equine hoof
Triangular horny structure, central sulcus if the cleft, and rests on digital cushion
What is the lateral cartilages of the equine hoof
Extend proximally from distal phalanx to create a pump
What are the 5 layers of the equine corium
Laminar, perioplic, coronary, sole, and frog
What is the laminar corium
Btw hoof wall and third phalanx
What are horns
Mass of horny keratin like the hoof, grow continuously in both sexes, and structurally similar to hair where the originate in the epidermal
What are antlers
Primarily on males, dermal in origin, shed annually, bony protuberance from the skull, lack central core and internal blood supply
What is pruritus
Itching
What is alopecia
Hair loss
What is hyperkeratosis
Thickened skin
What is pyoderma
Bacterial skin infection
What is hyperpigmentation
Increased pigment in skin
What are the ways to determine the pathology w/ diagnostics
History, PE, skin scrape, imression smear, tape preparation, trichogram, and fungal culture
What is a hot spot
Acute moist dermaitis typically brings pruritus, moisture, and pyoderma
What is stud tail
Supracaudal gland hyperplasia or tail gland hyperplasia is caused by hypersecretion of the glands in the supracaudal organ
What are comedones
Hair follicles blocked by an excess of skin oils and keratin
What does a skin scrape look for
Mange
What does impression smear and tape preparation look for
Yeast and bacteria
What is a trichogram
Pluck hairs to identify ring worm
What are the 2 categories of seborrhea
Oleosa over production of oil leading to clumped hair and sicca not enough production of oil resulting in dry flakes
