Ch. 4 - Tissues

Connective tissue does much more than just connect body parts Name the (5) major functions

(1) Binding and supporting - bone/cartilage (2) Protecting - bone/cartilage (3) Insulating - Fat (4) Storing reserve fuel - Fat (5) Transporting substances within the body - Blood

Connective tissues share two characteristics that together set them apart from other primary tissues

(1) Extracellular matrix - consist largely of non-living extracellular matrix which often separates the living cells of tissue - Because of its matrix, connective tissue can * bear weight * withstand great tension * endure abuses no other tissue can (2) Common origin - All connective tissues arise from mesenchyme (an embryonic tissue)

State the major characteristics of epithelial tissue (5)

(1) Polarity: two layers, - Apical surface: exposed to outside of body or cavity of internal organ - Basal Surface: attached to underlying CT (2) Specialized Contact - fit closely together to form sheets via tight junctions/desmosomes (3) Supported by Connective Tissue - via a basement membrane (Basal Lamina) (4) Avascular but Innervated - can't be too thick as nutrients transported via diffusion (5) Regeneration - high regeneration capacity

List the main functions & give examples Epithelial Tissue

(1) Protection: - Mechanical: as a barrier - Chemical: Cells linning stomach & HCl stomach acids - Biological: as a barrier - UV: Melanin in skin (2) Absorption/Diffusion - Oxygen/CO2 in Alveoli (3) Filtration - Pressure - Blood vessels in kidneys form urine (4) Excretion - Mucociliary Escalator in bronchi via cilia (5) Secretion - H+ move from blood to urine (6) Sensory reception

Define Cartilage & Give the (3) types of Cartilage

- 1 of 4 types of Connective Tissue - avascular and not innervated - stands up to both tension and compression - tough but flexible - qualities are between those of dense connective tissue and bone - receives its nutrients by diffusion from blood vessels located in the connective tissue layer (perichondrium) surrounding it - NO CANALICULI - Always thin, never thick because of diffusion aspect - contains large amount of tissue fluid (80% water) - Cell type: Chondroblasts: grows cartilage - Chondroblasts produce new matrix until the skeleton stops growing at the end of adolescence - Chondrocytes (mature cell) found in lacune Types: 1.) Hyaline cartilage 2.) Elastic cartilage 3.) Fibrocartilage (each dominated by a particular fiber type)

Define a gland

- A gland consists of one or more cells that make and secrete a particular product. -This product, called a secretion, is an aqueous fluid that usually contains proteins - Some glands release a lipid- or steroid-rich secretion.

Define epithelial tissue

- A primary tissue that covers the body surface or lines its internal surface - a sheet of cells that covers a body surface or lines a body cavity - Form boundaries between different environments and nearly all substances received or given off by the body must pass through an epithelium ex. the epidermis of the skin lies between the inside and the outside of the body

Connective tissue is also home to an assortment of other cell types, such as: (4)

- Adipocytes (adipose/fat cells) - store energy - White Blood Cells (Leukocytes) - includes neutrophils, eosinophils & lymphocytes - Mast Cells - inflammatory response/Immune sysytem - Macrophages - consume foreign invaders/dead tissue

In epithelial sheets, what is the purpose of a basement membrane and what is it composed of?

- Basement membrane reinforces the epithelial sheet, helps it resist stretching and tearing, and defines the epithelial boundary - The basement membrane consists of two layers: 1.) basal lamina (above) 2.) reticular lamina (deep)

Hints for Identifying Dense CT: Irregular (DICT)

- Bunches of collagen fibers run irregularly through the tissue - looks messy - Spaces between bundles are visible - Usually stained pink or blue - Nuclei of fibroblasts may not look as flat as with DRCT - More space than DRCT tissue - Blood Vessles can run through & be seen

Hints at identifying Loose CT Proper: Adipose

- Cells look like balloons or bubbles pushed against one another - Since the cell is filled with TAG's, the nucleus is pushed to the edge of the cell - Very little Matrix

Explain how keratinized Stratified Squamous Epithelial Tissue is released? & What purpose does the glucolipid server?

- Cells produced Keratin at the basal level - Cells secrete glycolipid and fill with keratin as they are pushed upwards - Superficial cells are dead. - Glycolipid: Acts like a glue bonding all the dead keratinized cells together

Hints for Identifying CT: Hyaline Cartilage (Gristle)

- Chondrocytes can be seen in lacunae depending on magnification - Lacunae usually look slightly larger than the cells - Matrix is smooth - No fibers are visible

For each of the following connective tissues: 1) recognize and be able to draw them 2) describe the fibers, cells, and ground substance 3) give examples of where they can be found 4) state the function of each 5) explain how their structure aids their function Dense CT: Regular (DRCT)

- Dense w/ Fibers, little ground substances - Predominately collagen fibers - Collagen fibers run in same direction - white, flexible structures with great resistance to tension where tension is exerted in a single direction - Crowded between the collagen fibers are rows of fibroblasts (stem cells) continuously manufacture the fibers and a small amount of ground substance - few cells other than fibroblasts - Fibroblasts smashed - Poorly vascularized (unlike areolar tissue) due to tightly packed collagen - Injuries take longer to heal Structure: - Slightly wavy - allows the tissue to stretch a little, but once the fibers straighten out, there is no further "give" to this tissue - Fibers Parallel to the direction of pull Function: - Tendons (Bone to muscle) - Aponeurosis (muscle to muscle/bone) - Ligaments (Bone to Bone) - Joints

For each of the following connective tissues: 1) recognize and be able to draw them 2) describe the fibers, cells, and ground substance 3) give examples of where they can be found 4) state the function of each 5) explain how their structure aids their function Dense CT: Irregular (DICT)

- Dense w/ Fibers, little ground substances - Predominately collagen fibers - same structural elements as the regular variety - the bundles of collagen fibers are much thicker and they are arranged irregularly - Collagen runs in all directions - forms sheets in body areas where tension is exerted from many different directions - Fibroblast (stem cells) present - Very vasular Found: - muscle sheath (epimysium) - Facsia - Periostea & Perichondria - Under epithelium & areolar tissue of bladder (prevents overexpansion) - in the skin as the leathery dermis (bellow epithelium of skin) - fibrous joint capsules - fibrous coverings that surround some organs (kidneys, bones, cartilages, muscles, and nerves).

For each of the following connective tissues: 1) recognize and be able to draw them 2) describe the fibers, cells, and ground substance 3) give examples of where they can be found 4) state the function of each 5) explain how their structure aids their function Dense CT: Elastic

- Dense w/ Fibers, little ground substances - Predominately elastic fibers - A few ligaments, such as those connecting adjacent vertebrae, are very elastic - The dense regular connective tissue in those structures is called elastic connective tissue - many of the larger arteries have stretchy sheets of elastic connective tissue in their walls - Dense elastic fibers running in the same direction. - Fibroblasts are present but are not visible - Fibers usually have a coiled or wavy appearance - Fibers may be thick or thin. Function: - provides recoil, absorbs shock Example: - Allows tissue to recoil after stretching, maintains the pulsatile flow of blood through arteries - Aids passive recoil of lungs following inspiration Found in: - blood vessels - heart valves - elastic ligaments (Ligamentum Flavum, Anterior Long. Lig, Supraspinous Ligament) - Fundiform Ligaments (base of penis) - walls of bronchial tubes

Identify and give the function of: - Eccrine glands in the skin. Also called Merocrine Sweat Glands (release their product by exocytosis)

- Far more numerous than apocrine sweat glands - Each is a simple, coiled, tubular gland - (Sweat) is a hypotonic filtrate of the blood that passes through the secretory cells of the sweat glands and is released by exocytosis - Secretion type: Merocrine (exocytosis) Sweat Content: - Sweat is acidic with a pH between 4 and 6. - Sweat is 99% water with some: * salts (mostly sodium chloride) * metabolic wastes (urea, uric acid, and ammonia) * Dermcidin (microbe-killing peptide) Location: - Everywhere but particularly abundant on: * the palms * soles of the feet * forehead Structure: - The secretory part lies coiled in the dermis - the duct extends to open in a funnel-shaped pore at the skin surface - does not need a hair follicle like Sebecus glands Function: - the major role is to prevent body from overheating - Heat-induced sweating begins on the forehead and spreads inferiorly over the remainder of the body - Emotionally induced sweating—the so-called "cold sweat" brought on by fright or nervousness—begins on the palms, soles, and axillae (armpits) and then spreads to other body areas

Hints on Identifying Loose CT Proper: Areolar (3)

- Fibers look scattered & cells are found between them - Looks "messy" - Collagen fibers are very thick & stained pink/blue - matrix is mostly water (Ground Substances) Note: You don't need to differentiate between reticular & elastic fibers or the type of cells in microscope slide.

For each of the following connective tissues: 1) recognize and be able to draw them 2) describe the fibers, cells, and ground substance 3) give examples of where they can be found 4) state the function of each 5) explain how their structure aids their function CT: Elastic Cartilage

- Histologically, nearly identical to hyaline cartilage but has many more elastic fibers - Found where strength and exceptional stretchability are needed Structure: - Densely packed elastin fibers run through the cartilage matrix in different directions - Chondrocytes are located within lacunae Function: - The elastin protein recoils to maintain original shape of the tissue Found: - forms the "skeletons" of the external ear - the epiglottis - Auditory tube (throat to middle ear)

Where is non-keratinized Stratified Squamous Epithelial Tissue found? And is the superficial layer dead like in Keratinized Stratified Squamous Epithelial Tissue?

- Inside of mouth - Esophagus - Vagina No, the superficial layer is still alive unlike Keratinized Stratified Squamous Epithelial Tissue

Hints for Identifying CT: Elastic Cartilage

- Lacunae and chondrocytes will appear round - Elastic fibers will stain darkly and be seen running in multiple directions.

What purpose does microvilli serve on the apical surface of Epithelium?

- Microvilli tremendously increase the exposed surface area. - Seen in epithelia that absorb or secrete (export) substances (those lining the intestine or kidney tubules, for instance)

Define: Connective Tissue

- Primary tissue - form and function vary extensively - Not exposed to the outside (unlike Epithelia) - Cells not attached, separated by Matrix - Functions include: 1.) support 2.) storage 3.) protection

For each of the following connective tissues: 1) recognize and be able to draw them 2) describe the fibers, cells, and ground substance 3) give examples of where they can be found 4) state the function of each 5) explain how their structure aids their function CT: Fibrocartilage

- Structurally, fibrocartilage is intermediate between hyaline cartilage and dense regular connective tissues - Durable: shock absorption - resists both compression and tension well - found where strong support and the ability to withstand heavy pressure are required Structure: - Thick collagen fibers - Rows of chondrocytes (a cartilage feature) alternate with rows of thick collagen fibers (characteristic of dense regular connective tissue) Found: - intervertebral discs (resilient cushions between the bony vertebrae) and - Menisci of the knee - Pubic Symphysis

Connective Tissue What are the "Fibers" inside Connective Tissue? & What are the (3) types of "FIbers" found in Connective Tissue Matrix?

- The fibers of connective tissue are proteins that provide support 1.) Collagen - like rope (strongest & most abundant ) 2.) Elastic - like rubber bands (Found in skin, lungs, blood vessel walls) 3.) Reticular fibers - like netting (found in basement membrane of epithelial tissue)

Identify and give the function of: - Apocrine glands in the skin Also called Merocrine Sweat Glands (release their product by exocytosis)

- The less numerous type of sweat glands - Sweat is viscous & has a milky/yellowish color - cells do not constantly divide like sebaceous glands - Secretion type: Merocrine (exocytosis) Sweat Content: - Produces a sweat containing: * water * salts * proteins * fatty acids (Sialic Acid) Location: - largely confined to the axillary and anogenital areas Structure: - their ducts empty into hair follicles - Larger than eccrine glands - lie deeper in the dermis or even in the subcutaneous tissue - secretion is odorless, but when bacteria on the skin decompose its organic molecules, it takes on a musky and generally unpleasant odor, the basis of body odor. Function: - Precise function is not yet known - May act as a sexual scent gland - glands begin functioning at puberty under the influence of the male sex hormones (androgens) - play little role in maintaining body temperature

Classification of Epithelial Tissue Describe how epithelia tissue is named

- The name of each epithelium has two parts, just like a first and last name. - The first name indicates the number of cell layers present. - Based on the number of cell layers, there are simple and stratified epithelia

Exocrine Glands How do exocrine glands secrete their products in unicellular vs multicellular states?

- Unicellular glands do so directly (by exocytosis), - Multicellular glands do so via an epithelium-walled duct that transports the secretion to the epithelial surface

Hints for Identifying Dense CT: Regular (DRCT)

- Unidirectional collagen fibers, densely packed - Usually stained pink, sometimes blue - Nuclei of fibroblasts can be seen flattened between the fibers

Loose CT Proper: Reticular How are reticular fibers used in lymph nodes?

- When lymph fluid enters a lymph node, it slows down due to the dense reticular fiber network - Within the reticular tissue will be immune system cells - As the fluid slows, the immune cells can grab foreign material and get rid of it (Macrophages) - Reticular fibers of the lymph node act as a sieve to filter the fluid Note: The spleen does the same thing with blood

Describe the following Cell Junction & give example 3 of 3 Gap Junctions

- a communicating junction between adjacent cells - At gap junctions the adjacent plasma membranes are very close & cells are connected by hollow cylinders called connexons (transmembrane proteins) - transmembrane proteins determine what can pass through them from one cell to its neighbor - Ions, simple sugars, and other small molecules pass through these water-filled channels - Gap junctions are present in electrically excitable tissues where ion passage from cell to cell helps synchronize their electrical activity and contraction Ex: - Heart - Smooth muscle - Control of Cilia ( Moves in Wave - Synchronized)

Describe the following Cell Junction & give an example 1 of 3 Tight Junctions

- a series of integral protein molecules in the plasma membranes of adjacent cells fuse together like the zipper of a Ziplock bag - forms an impermeable junction that encircles the cell and separates one fluid-filled compartment from another - help prevent molecules from passing through the extracellular space between adjacent cells including water - restrict the movements of membrane proteins Ex tight junctions between epithelial cells lining the digestive tract keep digestive enzymes & microorganisms in the intestine from seeping into the bloodstream

For the following epithelial tissues: 1) recognize them 2) give/recognize examples of where each can be found 3) explain their function 4) explain their structure and/or any specializations in functions Simple Columnar

- a single layer of tall, closely packed cells - aligned like soldiers in a row - Oval Nucleus - lines the digestive tract from the stomach to rectum - mostly associated with absorption and secretion, and the digestive tract lining - Columnar cells lining the intestine have unicellular mucus-producing glands called goblet cells. These produce mucus to allow things to move through the digestive tract. - some simple columnar epithelia display cilia on their free surfaces but most have microvilli

For the following epithelial tissues: 1) recognize them 2) give/recognize examples of where each can be found 3) explain their function 4) explain their structure and/or any specializations in functions Simple Cuboidal

- consists of a single layer of cells as tall as they are wide - generally spherical nuclei stain darkly - Important functions: secretion and absorption - forms the walls of the smallest ducts of glands and of many kidney tubules.

If we summarized the role of each primary tissue in a single word, we could say that: - epithelial tissue ___________ - connective tissue ___________ - muscle tissue ___________ - nervous tissue ____________

- epithelial tissue covers - connective tissue supports - muscle tissue moves - nervous tissue controls

For the following epithelial tissues: 1) recognize them 2) give/recognize examples of where each can be found 3) explain their function 4) explain their structure and/or any specializations in functions Simple Squamous

- flattened - cytoplasm is sparse - resemble a tiled floor (Top View) - resemble fried eggs (Side View) - Thin and often permeable - found where filtration or exchange of substances by rapid diffusion is a priority Ex. Kidneys: forms part of the filtration membrane that filters blood to make urine. Ex.Lungs: forms the walls of the air sacs across which gas exchange occurs (Alveoli) Ex. Lining of Body Cavities (Peritoneum) - 1 Layer of Simple Squamous + 1 Layer Areolar CT

For the following epithelial tissues: 1) recognize them 2) give/recognize examples of where each can be found 3) explain their function 4) explain their structure and/or any specializations in functions Transitional

- forms the lining of hollow urinary organs, which stretch as they fill with urine - Cells of its basal layer are cuboidal or columnar - apical cells vary in appearance, depending on the degree of distension (stretching) of the organ - Apical cells have rounds nuclei - When the organ is distended with urine, the transitional epithelium appears to thin from about six cell layers to as few as three, and its domelike apical cells flatten and become squamous like - allows a greater volume of urine to flow through a tubelike organ - In the bladder, it allows more urine to be stored - Found in ureters - Although it gets thinner as the size of the bladder increases, there is no increase in tension so a lot of urine can be stored without tearing the transitional epithelium - Unfolds when stretched

Name one noticeable difference between different types of connective tissue

- how richly they are supplied by blood vessels - Cartilage is avascular - Dense connective tissue is poorly vascularized, and the other types of connective tissue have a rich supply of blood vessels (i.e bone)

Where is Epithelia Tissue found?

- lines all internal tubes and hollow organs - Includes the heart, blood vessels, trachea, stomach, bladder, ureters - When you are looking at epithelium under a microscope, it will always be on the edge (next to an open space) - Epithelium also forms exocrine glands like sweat glands and those producing mucus in the digestive tract ("crino" = secrete; "exo" = to the outside).

For each of the following connective tissues: 1) recognize and be able to draw them 2) describe the fibers, cells, and ground substance 3) give examples of where they can be found 4) state the function of each 5) explain how their structure aids their function Loose CT Proper: Areolar

- matrix is mostly water (Ground Substances) - not very strong, easily torn - most widely distributed connective tissue in the body - universal packing material between other tissues - binds body parts together while allowing them to move freely over one another - It is the connective tissue that most epithelia rest on - present in all mucous membranes - source of oxygen for epithelial cells Function: - Supporting and binding other tissues (job of fibers) - Holding body fluids (job of ground substance) - Defending against infection (WBC & Macrophages) - Storing nutrients as fat in adipocytes (Fat Cells) Structure: - loose arrangement of its fibers - Mostly ground substance/empty - because of loose nature, provides a reservoir of water/salts for surrounding body tissue (more fluid than entire bloodstream) - All body cells obtain nutrients & release waste into this "tissue fluid" - ground substance is viscous like molasses (due to high hyaluronic acid) - contain adipose, fibroblast & WBC's - contains collagen, elastic & reticular fibers

Identify and give the function of: - Sebaceous in the skin

- oil gland - simple branched alveolar glands - secrete an oily substance called sebum - cells get bigger as they reach the surface - Cells constantly dividing - when cells reach the top, they exocytosis via Holocrine (cells blow up) Sweat Content: - Sebum Location: - found all over the body except in thick skin of palms & soles Structure: - sebaceous glands develop as outgrowths of hair follicles and secrete sebum into a hair follicle via a duct, or occasionally to a pore on the skin surface - Arrector pili contractions force sebum out of the hair follicles to the skin surface Function: Sebum: * softens and lubricates the hair & skin * prevents hair from becoming brittle * slows water loss from the skin - bactericidal action - Sebaceous glands increase their activity during puberty under the influence of male sex hormones (Androgen/testosterone) - Blockage = acne (bacterial infection)

For the following epithelial tissues: 1) recognize them 2) give/recognize examples of where each can be found 3) explain their function 4) explain their structure and/or any specializations in functions Stratified Cuboidal

- quite rare in the body - mostly found in the ducts of some of the larger glands (sweat glands, mammary glands) - It typically has two layers of cuboidal cells - look for round nuclei

For each of the following connective tissues: 1) recognize and be able to draw them 2) describe the fibers, cells, and ground substance 3) give examples of where they can be found 4) state the function of each 5) explain how their structure aids their function Loose CT Proper: Reticular

- resembles areolar connective tissue, but the only fibers in its matrix are reticular fibers - form a delicate network along which fibroblasts called reticular cells are scattered - reticular tissue is limited to certain sites - support many free blood cells (mostly lymphocytes) in lymph nodes, the spleen, and bone marrow - Excess fluid that has left blood vessels is returned to the circulatory system through lymphatic vessels - Lymph nodes are found along the lymphatic vessels Structure: - matrix is still mostly water (Ground Substances) Found: - Lymph Nodes - Spleen (old RBC's) - Bone Marrow

Hints at Identifying Loose CT Proper: Reticular

- reticular fibers appear as thin black lines in microscope slides - The fibers often look broken or torn due to the process of cutting the tissue and putting it on a slide - In these examples from the spleen, you can see red blood cells moving through the tissue. Old red blood cells will be removed, along with any contaminants, by immune system cells - Looks like Cherry Blossoms/Grapes Pink Objects: Are RBC's (Spleen)

Describe the following Cell Junction & give example 2 of 3 Desmosomes

- serve as anchoring junctions—mechanical couplings scattered like rivets along the sides of adjacent cells to prevent their separation - held together by thin linker protein filaments (cadherins) that extend from the plaques and fit together like Velcro in the intercellular space - reduce the chance of the sheet tearing when it is subjected to pulling forces - abundant in tissues subjected to great mechanical stress - Part of Cytoskeleton - Includes Linker Proteins inside - Intermediate filament on outside - Plaque is located between Linker Protein & Intermediate Filament - The reason after a sunburn, skin sluffs off in one piece Ex: - Skin - Heart muscle

For each of the following connective tissues: 1) recognize and be able to draw them 2) describe the fibers, cells, and ground substance 3) give examples of where they can be found 4) state the function of each 5) explain how their structure aids their function Loose CT Proper: Adipose

- similar to areolar tissue in structure & function, but its nutrient-storing ability is much greater - adipocytes account for 90% of this tissue's mass - almost pure triglyceride occupies most of adipocyte's volume & displaces the nucleus to one side - richly vascularized - Very little Matrix - Adipose tissue is abundant, constitutes 18% of an average person's body weight Structure: - chicken-wire appearance - cells are packed closely together & scanty - displaces the nucleus to one side Function: - shock absorber - thermal & mechanical insulation - energy storage site Areas Found: - around kidney's - behind eyeballs - abdomen - hips - usually accumulates in subcutaneous tissue but can develop anywhere there's areolar tissue Note: - Very low metabolism - Just stores calories doesn't burn them - Adipose cells don't die, but they do undergo mitosis - Never die, just remove TAG from them when losing weight - only way to permanently get rid of is liposuction

For each of the following connective tissues: 1) recognize and be able to draw them 2) describe the fibers, cells, and ground substance 3) give examples of where they can be found 4) state the function of each 5) explain how their structure aids their function CT: Hyaline Cartilage (Gristle)

- the most abundant cartilage in the body - Chondrocytes account for only 1-10% of the cartilage volume - provides firm support with some pliability Structure: - the matrix appears glassy blue-white - Stiff & Smooth layer - contains large numbers of collagen fibers but they are not apparent under a microscope Found: - covers the ends of long bones as articular cartilage: providing springy pads that absorb compression at joints - supports the tip of the nose - connects the ribs to the sternum - supports most of the respiratory system passages (Trachea) - makes up most of the embryonic skeleton before bone forms - epiphyseal plates

Identify why both blood and bone is considered connective tissues

- the most atypical connective tissue - does not connect things or give mechanical support - classified as connective tissue because it develops from mesenchyme and consists of blood cells surrounded by a nonliving fluid matrix called blood plasma - The "fibers" of blood are soluble protein molecules that precipitate, forming visible fiber like structures during blood clotting (Fibrinogen to Fibrin to clot) - transport vehicle for the cardiovascular system, carrying nutrients, wastes, respiratory gases, and many other substances throughout the body

For the following epithelial tissues: 1) recognize them 2) give/recognize examples of where each can be found 3) explain their function 4) explain their structure and/or any specializations in functions Stratified Squamous (keratinized & non-keratinized)

- the most widespread of the stratified epithelia - Composed of several layers - it is thick and well suited for its protective role in the body - can also absorb medication via mouth/skin - Its free surface cells are squamous, and cells of the deeper layers are cuboidal or columnar - found in areas subjected to wear and tear, and its surface cells are constantly being rubbed away and replaced by division of its basal cells - Because epithelium depends on nutrients diffusing from deeper connective tissue, epithelial cells farther from the basement membrane are less viable and those at the apical surface are often flattened and may even be dead Ex. forms the external surface of the skin and extends a short distance into every body opening that is directly continuous with the skin - outer layer, or epidermis, of the skin is keratinized, meaning its surface cells contain keratin, a tough protective protein - other stratified squamous epithelia of the body are nonkeratinized (Mouth, Part of Esophagus, Vagina)

For the following epithelial tissues: 1) recognize them 2) give/recognize examples of where each can be found 3) explain their function 4) explain their structure and/or any specializations in functions Pseudostratified Columnar (Always has Cilia)

- vary in height - all cells reach basement membrane - All of its cells rest on the basement membrane, but only the tallest reach the free surface of the epithelium - Because the cell nuclei lie at different levels above the basement membrane, the tissue gives the false (pseudo) impression that several cell layers are present; hence "pseudostratified." - The short cells are relatively unspecialized and give rise to the taller cells - like the simple columnar variety, they secrete or absorbs substances - Also contains Goblet Cells - A ciliated version containing mucus-secreting goblet cells lines most of the respiratory tract (trap & remove dust) - Trachea/Bronchioles/URT when it has cilia, the correct name is: Pseudostratified Ciliated Columnar Epithelium

There are four main classes of connective tissue and several subclasses Name the (4) main classes

1.) Connective Tissue Proper - Loose & Dense (which includes fat and the fibrous tissue of ligaments) 2.)Cartilage - Supporting 3.) Bone - Supporting 4.) Blood/Lymph - Watery

Columnar cells are mostly associated with absorption and secretion, and the digestive tract lining has two distinct modifications that make it ideal for that dual function: Name the (2) distinct modifications

1.) Dense microvilli on the apical surface of absorptive cells 2.) Tubular glands (Goblet Cells) made primarily of cells that secrete mucus-containing intestinal juice

We have two types of sweat gland. Name them both

1.) Eccrine 2.) Apocrine These secretory cells are associated with myoepithelial cells

Four primary tissue types interweave to form the "fabric" of the body. Name these basic tissues and their function

1.) Epithelia - lines all hollow spaces found in the body Ex. bladder, blood vessels, intestines, surface of skin 2.) Connective - all tissue types that connect or hold together different parts of the body Ex. blood to bone 3.) Muscle - all types of tissue that contracts 4.) Nervous tissue - cells that can transmit action potentials

Connective Tissue Connective Tissue Cells: Name the (3) types of cells - both immature (-blast) & mature forms (-cytes) + Describe their function

1.) Fibroblasts become fibrocytes. (connective tissue proper) 2.) Chondroblasts become chondrocytes. (cartilage) 3.) Osteoblasts become osteocytes. (bone) - immature blast cells are actively mitotic - Each type of blast cell secretes the ground substance and the fibers characteristic of their particular matrix - Once they synthesize the matrix, the blast cells assume their mature, less active -cyte form - mature cells maintain the health of the matrix - if the matrix is injured, they can easily revert to their more active blast form to repair and regenerate the matrix

Connective tissues have three main components: Name them & which components make up Extracellular Matrix

1.) Ground substance - can be fluid or solid 2.) Fibers - Collagen: rope like - Elastic: rubberband like - Reticular: Netting like 3.) Cells Note: Ground Substances + Fibers = Extracellular Matrix

Connective tissue proper has two subclasses, name them and any sub-categories

1.) Loose connective tissues - areolar - adipose - reticular 2.) Dense connective tissues - dense regular - dense irregular - elastic

Name the (3) kinds of cell junctions seen in epithelia

1.) Tight Junctions 2.)Desmosomes 3.) Gap Junctions

Adjacent to the basal surface of epithelium is a thin supporting sheet called the ____________ - Also give its function

Adjacent to the basal surface of epithelium is a thin supporting sheet called the basal lamina (basement membrane) - adhesive sheet consists largely of glycoproteins secreted by the epithelial cells plus some fine collagen fibers. - The basal lamina acts as a selective filter that determines which molecules diffusing from the underlying connective tissue are allowed to enter the epithelium. - The basal lamina also acts as scaffolding along which epithelial cells can migrate to repair a wound

Explain the formation of multicellular exocrine & endocrine glands

All Multi cellular epithelial glands form by invagination (inward growth) of an epithelial sheet Exocrine Glands: - retain the connecting cells which form a duct that transports secretions to the epithelial surface Endocrine Glands: - lose their ducts during development - they recreate hormones into the interstitial fluid - these hormones then enter the blood

All epithelial sheets rest upon and are supported by _____________ ____________.

All epithelial sheets rest upon and are supported by connective tissue

Although epithelium is avascular (contains no blood vessels), it is still ________________.

Although epithelium is avascular (contains no blood vessels), it is still innervated (supplied by nerve fibers)

Although some apical surfaces are smooth and slick, most have _______________, fingerlike extensions of the plasma membrane

Although some apical surfaces are smooth and slick, most have microvilli, fingerlike extensions of the plasma membrane

What type of CT is always found under the basement membrane Basil Lamina?

Areolar CT - The blood vessels from Areolar CT provides the nutrients for the Epithelial Tissue above it (via diffusion)

As long as epithelial cells receive adequate ____________, they can replace lost cells by cell division

As long as epithelial cells receive adequate nutrition, they can replace lost cells by cell division

Why do cancers have origins to Epithelia tissue?

Because Epithelia Tissue is so mitotically active

Define: histology

Branch of anatomy dealing with the microscopic structure of tissue

How does Cholera effect Tight Junctions?

Cholera break down the Tight Junction in the digestive tract and massive amounts of water is lost via BM's

_______________ _______________ is the Most Abundant and Widely Distributed Tissue in the Body

Connective Tissue is the Most Abundant and Widely Distributed Tissue in the Body

Name the two layers under Transitional Epithelium

Directly under: Areolar CT Under Areolar CT: DICT for increased strength

Compare & Contrast: Eccrine VS Apocrine

Eccrine: - Small Lumen - Stratified Cuboidal Epithelium - Ubiquitous - Everywhere on body Apocrine: - Large Lumen - Simple Cuboidal Epithelium - Anogenital Region Only

Name the two simple squamous epithelia in the body have special names that reflect their location

Endothelium ("inner covering") - provides a slick, friction-reducing lining in lymphatic vessels & in all hollow organs of the cardiovascular system (blood vessels and the heart). * Tunica Intima - Capillaries consist exclusively of endothelium, and its exceptional thinness encourages the efficient exchange of nutrients and wastes between the bloodstream and surrounding tissue cells. Mesothelium ("middle covering") - found in serous membranes, the membranes lining the ventral body cavity and covering its organs.

Compare Connective Tissue to Epithelia Tissue

Epithelia Tissue - close fitting cells - no matrix - polarity Connect Tissue - cells far apart - lots of matrix - no polarity

If epithelium is avascular, how do they receive nutrients from the body?

Epithelial cells are nourished by substances diffusing from blood vessels in the underlying connective tissue.

Epithelial tissue is the only tissue type that has polarity, that is, an apical and a basal surface. Why is this important?

Epithelial tissue lines body cavities and covers the body's external surface; thus polarity with one free (apical) surface is a requirement.

Explain the function of glandular epithelia & How they are classified

Glandular cells obtain needed substances from the blood and transform them chemically into a product that is then discharged from the cell Classified by: (1) Where they release their product: - Endocrine (internally) vs Exocrine (Externally) (2) Number of Cells: - Unicellular vs Multicellular

Connective Tissue What is "Ground Substance"? Identify its (3) separate components

Ground substance is the unstructured material that fills the space between the cells and contains the fibers Components: 1.) Interstitial fluid 2.) Cell adhesion proteins 3.) Proteoglycans

Microvilli vs Cilia Give examples where you would find these components in epithelial tissue

Microvilli: Intestinal Tract Cilia: Respiratory passageways & uterine tubes

Give examples of: multicellular exocrine glands in the body & endocrine glands in the body

Multicellular Exocrine Glands examples - Liver (secrete bile) - Pancreas ( synthesizes digestive enzymes) - Salivary glands - Sweat glands - Mucous glands - Oil Glands Unicellular Exocrine Glands examples - Mucous Cells - Goblet Cells - Unicellular glands are sprinkled in the epithelial linings of the intestinal and respiratory tracts amid columnar cells

Does all epithelial tissue offer UV protection?

No, only the epidermis does as it contain Melanin. Epidermis is the only tissue that will be exposed to UV light

What is the easiest way to tell the difference between keratinized and nonkeratinized?

Nonkeratinized will have visible nuclei in the upper layers.

Some epithelia are pseudostratified. What does this mean?

Pseudostratified epithelia appear to be stratified because their cells' nuclei lie at different distances from the basement membrane. However, all cells rest on the basement membrane.

What type of epithelial tissue contain goblet cells and microvilli?

Simple Columnar Epithelial Tissue

Stratified epithelia are "built" for protection or to resist abrasion. What are the simple epithelia better at?

Simple epithelia are "built" to provide for efficient absorption and filtration across their thin epithelial barriers.

Epithelial Tissue - First Name Explain the difference between: simple epithelia vs. stratified epithelia

Simple epithelia: - a single cell layer - typically found where absorption, secretion, and filtration occur - where a thin epithelial barrier is desirable. Stratified epithelia - two or more cell layers stacked on top of each other - common in high-abrasion areas where protection is important ex. such as the skin surface & lining of the mouth.

Some epithelia, such as that lining the trachea (windpipe), have motile _________ that propel substances along their free surface

Some epithelia, such as that lining the trachea, have cilia that propel substances along their free surface

Epithelial Tissue - Last Name Explain the difference between: Squamous Cell vs Cuboidal Cells vs Columnar Cells

Squamous cells: flattened and scale-like (squam = scale) - Flat Nucleus Cuboidal cells: boxlike, approximately as tall as they are wide - Round Nucleus Columnar cells are tall and column-shaped - Oval Nucleus Note: the shape of the nucleus conforms to that of the cell. - Keep nuclear shape in mind when you attempt to identify epithelial types.

Simple epithelia are easy to classify by cell shape because all of the cells usually have the same shape. In stratified epithelia, however, cell shape differs in the different layers. What is the rule when naming stratified epithelia?

Stratified epithelia are named according to the shape of the cells in the apical layer.

What is another name for a sweat gland?

Sudoriferous Gland

What part of the PNS regulates sweating?

Sweating is regulated by the Sympathetic Nervous System which is one part of the autonomic nervous system (involuntary)

True or False All mature connective tissues except for bone, cartilage, and blood are connective tissue proper.

TRUE

What type of Epithelial tissue lines the bladder & ureters?

Transitional Epithelial Tissue

Adipose tissue is categorized as: White Fat vs Brown Fat What is the difference?

White Fat - stores nutrients, mainly for other cells - Primary fat found in adults Brown Fat - contains many mitochondria that use lipid fuels to generate heat (instead of generating ATP molecules) - bloodstream then carries this heat to warm the rest of the body - occurs mainly on the back of babies who (as yet) lack the ability to produce body heat by shivering - Small deposits occur in adults, mostly above the collarbones, on the neck and abdomen, and around the spine

Can matrix be both delicate/fragile and incredibly strong?

Yes, the matrix can be delicate and fragile to form a soft "packing" around an organ, or it can form "ropes" (tendons and ligaments) of incredible strength

Define: tissue

are groups of cells that are similar in structure and perform a common or related function

In between the epithelial and connective tissues is a?

basement membrane called Basal Lamina - sticky substance that helps hold the Epithelia cells to the underling tissue

Cell shape influences the shape of the ______________.

cell shape influences the shape of the nucleus

Epithelial cells fit closely together to form continuous sheets. The sides of adjacent cells are tied together by tight junctions and __________________.

epithelial cells fit closely together to form continuous sheets. The sides of adjacent cells are tied together by tight junctions and desmosomes - tight junctions prevent substances from leaking through spaces between cells and that desmosomes keep cells from pulling apart

What are myoepithelial cells?

specialized cells that contract when stimulated by the nervous system Their contraction forces the sweat into and through the gland's duct system to the skin surface

What are cell junctions?

the plasma membranes of adjacent cells are joined together by specialized cell junctions - allow neighboring cells to adhere & communicate - may aid or inhibit movement of molecules between or past cells - serve to tie cells together into tightly knit communities