Term
| what are the four different types of tissues in the body? |
|
Definition
| connective tissue, epithelium, muscle, and nervous |
|
|
Term
| what are the main different types of building block molecules in the human body? |
|
Definition
| proteins, carbs, lipids, nucleic acids, ions/minerals |
|
|
Term
| what is the nucleouls and what does it hold? |
|
Definition
| it is in the nucleus, it holds rna and is the source of ribosomes. |
|
|
Term
| What are the roles of the SR in the cell? |
|
Definition
| detoxification, calcium storage, and lipid synthesis |
|
|
Term
| what is the role of the goli? |
|
Definition
| packaging and modification - produces seceratory vessicles. |
|
|
Term
| what is an inactive metabolic state referred to as? |
|
Definition
|
|
Term
| what characteristics describe a quiescent state cell? |
|
Definition
| temporarily shut down, gets rid of what it doesnt need, gets smaller in size (atrophy). nucleus is darker and smaller due to (HETEROCHROMATIN) |
|
|
Term
| what is the chromatin referred to as when it is wravled tightly? |
|
Definition
|
|
Term
| what is another term for a normal healthy cell? |
|
Definition
|
|
Term
| what characteristics describe an active cell? |
|
Definition
| number of organelles increase, nucleus is very large and much paler (due to more unwravled chromatin). Cell gets larger (hypertrophy). |
|
|
Term
| what is the chromatin referred to as when it is unwravled? |
|
Definition
|
|
Term
| What gives us the best/worst magnification of cells? |
|
Definition
| Electron microscopy/Light microscopy |
|
|
Term
| What dye do we use most often and what does it stain blue, pink, and clear respectively? |
|
Definition
| H and E. It stains DNA and RNA blue; it stains proteins of all sorts pink; lipids, carbs, and H20 remain clear |
|
|
Term
| What is the composition of most extracellular matrices? |
|
Definition
| H20, electrolytes, metabolites (carbs, lipids, etc...), proteins (no nucleic acids) |
|
|
Term
| What are the different types of states extracellular matrices may take? |
|
Definition
| fluid, semifluid/gel, solid |
|
|
Term
| what are some different types of epithelium cell arrangements? |
|
Definition
| simple squamous, stratified squamous, simple columnar |
|
|
Term
| What is the definition of an organ? |
|
Definition
| multiple cells acting together to perform a common function. |
|
|
Term
| What are th functions of a membrane |
|
Definition
| 1. compartmentalize the cell into different aqueous microenvironments, each with their different functions and content. 2 interface with the different aqueous environments (recieve messages, contain identitiy tags, and adhere to structural supports) 3. selectively transport necessary substances through (selectively permeable) |
|
|
Term
| what can you use to see a membrane |
|
Definition
|
|
Term
| What are the two types of membrane lipids? |
|
Definition
| phospholipids and cholesterol |
|
|
Term
| What are the funcitons of MEMBRANE LIPIDS? |
|
Definition
create membrane fluidity/movement
permeable to hydrophobic molecules
impermeable to hydrophilic molecules |
|
|
Term
| What are the two types of membrane proteins? |
|
Definition
| peripheral (extrinsic) and integral (intrinsic) |
|
|
Term
| what are some functions of peripheral membrane proteins? |
|
Definition
attach cytoskeleton to membrane
part of the 2nd messenger systems |
|
|
Term
| integral membrane proteins sometimes have carb units attached to it. (true/false) |
|
Definition
|
|
Term
| what is the term referring to the amalgamation of all the carbs of transverse proteins to the point where a layer of carbs can be seen? |
|
Definition
|
|
Term
| What are the functions of integral membrane proteins? |
|
Definition
| adhesion, cell-cell recognition, receptor, transport, and signaling |
|
|
Term
| two most important membrane functions: |
|
Definition
1. act as a selective barrier b/n 2 environments
2. transport across the membrane |
|
|
Term
| How do lipids and gases cross membranes? |
|
Definition
|
|
Term
| how do ions and water pass membranes? |
|
Definition
| facilitated diffusion (through channel integrated proteins) |
|
|
Term
| how do glucose and AA pass through membranes? |
|
Definition
|
|
Term
| how do large molecules move across membranes? |
|
Definition
| endocytosis (phagocytosis is large amount while pinocytosis is small amount) |
|
|
Term
| What is the mitochondria responsible for? |
|
Definition
| energy production (through Krebs cycle, ETC, and oxidative phosphorylation) |
|
|
Term
| structure of mitochondria: |
|
Definition
| 2 membranes and 2 spaces (inner membrane has form folds) |
|
|
Term
| what are the form folds of the mitrochondria called? |
|
Definition
|
|
Term
| what are the components of the mitochondrial matrix? |
|
Definition
| DNA, ribosomes, and Ca++ (the only thing you can actually see from EM) |
|
|
Term
| what are ribosomes made of? |
|
Definition
|
|
Term
| what are the two types of Ribosomes and why are they different? |
|
Definition
| free and bound (to ER) they are only differ in their location. |
|
|
Term
| what is the function of the ribosome? |
|
Definition
|
|
Term
| what is another term for free ribosomes? |
|
Definition
| polyribosomes (bc they're are often many ribosomes reading one RNA strand at a time) |
|
|
Term
| is the SER always continuous with the RER? |
|
Definition
| no, it can but doesn't have to be. |
|
|
Term
| what are the purposes for the RER? |
|
Definition
synthesize proteins for export
synthesize membrane proteins
synthesize protein contents of membrane bound organelles
NOTICE THAT IT ONLY PRODUCES MEMBRANE ASSOCIATED PROTEINS |
|
|
Term
| RER is responsible for: forming, modifying, and ___________? |
|
Definition
| separating (keeping like proteins together. this is continued in the golgi complex) |
|
|
Term
| what prevents lipases from destroying the cell if they are released from the lysozome into the cell? |
|
Definition
| they work best in acidic conditions and are less effective out in the cytoplasm |
|
|
Term
| what are the main functions of the cytoskeleton? |
|
Definition
1. structural support
2. movement of organelles/cell |
|
|
Term
| What are the three different types of cytoskeletal proteins? |
|
Definition
| microfilaments, intermediate filaments, and microtubules |
|
|
Term
| microfilaments consist of both? |
|
Definition
| actin (structural support or movement) and myosin. |
|
|
Term
| what is the term for when proteins can breakdown and be used/ the term for when proteins are not changable? |
|
Definition
|
|
Term
| intermediate filaments are used primarily for ____________? |
|
Definition
|
|
Term
| T/F. Intermediate filaments tend to stay stable in their structure. |
|
Definition
|
|
Term
| Types of intermediate fillaments: |
|
Definition
1. epithelial cells use CYTOKERATINS
2. connective tissue cells use VIMENTIN
3. muscle cells use DESMIN |
|
|
Term
| What are the purposes of microtubules? |
|
Definition
| structural support and movement |
|
|
Term
| what is the name of the protein subunit dimer that makes up microtubules? |
|
Definition
|
|
Term
| are microtubules labile or stable? |
|
Definition
|
|
Term
| How is a microtubule structurally formed? |
|
Definition
| dimers of tubulin spiral around in a chain forming a tube. This tube pairs up with another tube forming a doublet. |
|
|
Term
| What are some examples in which microtubules are used? |
|
Definition
| centriole (flagella) and mitotic spendle |
|
|
Term
| What is cilia made of and in what arrangement? |
|
Definition
| microtubules, 9 + 2 formation (the two in the middle are not doublets) |
|
|
Term
| What is the structural significance of microvilli? |
|
Definition
| increased surface area (usually for absorption) |
|
|
Term
| What are the different types of intercellular junctions? |
|
Definition
| Tight junction (zonula occludens), zonula adherens (belt of adhesion), Gap junction (nexus - communicating junction), Desmosome (macula adherens), and hemidesmosome (1/2 desmosome) |
|
|
Term
| how many pairs of chromosomes are there in the human cell? |
|
Definition
|
|
Term
| what is another name for the plasma membrane? |
|
Definition
|
|
Term
| what are the main functions of integral proteins? |
|
Definition
| cell-cell recognition, adhesion, receptor, transport, and signalling |
|
|
Term
| what is the space called B/N all of the nuclei and the organelles in the cell membrane? |
|
Definition
|
|
Term
| what are the names of the faces of the golgi aparatus? |
|
Definition
| cis (forming) face and trans (maturing) face |
|
|
Term
| what is another name for the fibrilar bundle of flagellum usually positioned in a 9 + 2 fashion? |
|
Definition
|
|
Term
| what are some examples of where microtubules are used? |
|
Definition
| centrioles, flagella, cilia |
|
|
Term
| what are attached to the microtubule dimers that allows for harnessing energy from ATP? |
|
Definition
|
|
Term
| what is the assembly of the six proteins that form a gap junction called? |
|
Definition
|
|
Term
| what is the name for the junction formation in cells and in what order do they occur? |
|
Definition
name: junctional complex
order: 1. zonula occlusens (tight junction)
2. zonula adherens
3. desmosome (macula adherens) |
|
|
Term
| what is the term for a cell with no nuclei? |
|
Definition
|
|
Term
| what are the proteins inside the nucleus (structural materials) called? |
|
Definition
| fibronous layer (found right inside the nuclear membrane |
|
|
Term
| T/F. Nuclear membrane is continuous with smooth ER? |
|
Definition
| False. Nuclear membrane is continuous with rough ER. |
|
|
Term
| are there pores in the nuclear membrane? |
|
Definition
| yes (selectively permeable) |
|
|
Term
| what do nuclear pores allow out of the nucleus? |
|
Definition
|
|
Term
| what do the nuclear pores allow in? |
|
Definition
| hormones and other messangers, nucleo proteins, metabolites (ATP) |
|
|
Term
| What is the layer between the nuclear membranes called? |
|
Definition
|
|
Term
| what is the name of the DNA folding proteins? |
|
Definition
| histones (nucleoproteins) |
|
|
Term
| what form does the DNA begin to form following the wrapping around the histones and before starting to form the loop like strands? |
|
Definition
|
|
Term
| about how many genes are there in a human? |
|
Definition
|
|
Term
| what is the term that describes the process of observing the chromatin in their wravled state and comparing them? |
|
Definition
|
|
Term
| What are the phases of mitosis? |
|
Definition
| prophase, metaphase, prophase, telophase |
|
|
Term
| what happens in prophase? |
|
Definition
| chromatin begin to wravel and become distinct chromosomes, nuclear envelope begins to break down, spindles form at opposite ends of the cell |
|
|
Term
| what happens in metaphase? |
|
Definition
| chromosomes are lined at the metaphase plate |
|
|
Term
| what happens in prophase? |
|
Definition
| paired chromosomes move to opposite ends of the cell |
|
|
Term
| what happens in telophase? |
|
Definition
|
|
Term
| Recite the Cell Cycle starting in the interphase, G0 |
|
Definition
|
|
Term
|
Definition
| period prior to the synthesis of DNA - cell increases in mass in prep for cell division. |
|
|
Term
| what happens in the S phase? |
|
Definition
|
|
Term
| what happens in the G2 phase? |
|
Definition
| the period after the DNA is synthesized (replicated) and prior to the start of prophase. The cell continues to make proteins and increase in size. |
|
|
Term
| What two cases call for apoptosis? |
|
Definition
| embryology (forming new structures and getting rid of old ones) and just when cells begin to loose function and need to be replaced |
|
|
Term
| what are the steps of apoptosis? |
|
Definition
| a message is recieved (either from inside or outside the cell), release of capsase enzymes results in the degradation of all of the cell's organelles and structures, nucleus shrinks (pyknotic), karyorrhexis occurs (the fragmentation of the cell to form bite size peices for the macrophages), macrophages come in and clean up the bits and peices |
|
|
Term
| Where are the three gerenal places where epithelium can be found? |
|
Definition
| body surfaces, body cavities, and holow organs. |
|
|
Term
| What is the main purpose of epithelium? |
|
Definition
| to act as the interface b/n different biological compartments (like a membrane) |
|
|
Term
| What are some of the functions of epithelium? |
|
Definition
| protection, compartmentalize, mediate exchange b/n biological compartments, and secretion |
|
|
Term
| what are the basic structures common to all types of epithelium? |
|
Definition
1. continuous sheets of cells
2. polarity (apical, lateral, and basilic surfaces)
3. apical surface specializations
4. Lateral surfaces |
|
|
Term
| what are four different types of external/internal apical surfaces and their purpose? |
|
Definition
| flat (most epithelial cells - no real significant purpose); microvilli (increase surface area for absorption; cilia (movement of whatever is in the lumen); keratin covering (used for protection - ONLY EXISTS WITH MULTIPLE LAYER EPITHELIUM. NEVER SINGLE LAYER); Terminal Web (structural support) |
|
|
Term
| What is it called when actin is accumulated on the internal apical surface of an epithelium cell and is used for structural support? |
|
Definition
|
|
Term
| What is always located directly under a layer of epithelium? |
|
Definition
| lamina propria (basement membrane is under this |
|
|
Term
| what are the different intercellular junctions and the order in which they appear? |
|
Definition
1. tight junction (zonula oclusens) - impermeable
2. zonlua adherens - actin - in the case of epithelia it joins with the actin of the terminal web
3. Gap Junction - communication
4. Desmosomes (macula adherens) - intermediate filaments
Optional 5th - sometimes there are half desmesomes called hemidesmosomes. They are seen in such situations as when lamina propria binds to the basement membrane of epithelia. |
|
|
Term
| can the basement membrane be seen with LM? |
|
Definition
| Well, the BM is right on the line of resolution for the LM, but it can defintely be seen in EM. |
|
|
Term
| What does the basemement membrane look like under electron microscopy? |
|
Definition
| it looks like a sandwich with a dark middle layer and two lighter outer layers. |
|
|
Term
| What is the basement membrane? |
|
Definition
| the linear array of proteins that epithelial cells rest on. |
|
|
Term
| what are the functions of the basement membrane? |
|
Definition
structural - component for epithelial cells to attach to
filtering - filters waste
influence cell polarity - basement adds direction
regulate epithelial cell proliferation |
|
|
Term
| what kind of junction is often seen on the basal side of the epithelial cell? |
|
Definition
|
|
Term
| what is the lamina propria and where is it located? |
|
Definition
| it is connective tissue (typically dense irregular CTP) that is located directly under the basement membrane. |
|
|
Term
| what is the main purpose of the lamina propria? |
|
Definition
1.its primary job is to provide support keeping the epithelia attached with hemidesmosomes
2. provide the epithelia with vascularature. |
|
|
Term
| what type of collagen is found in lamina propria? |
|
Definition
|
|
Term
| What does the term labile tissue refer to and what type of tissue does it describe? |
|
Definition
| it refers to continual cell death and renewal and epithelium cells are labile tissues. |
|
|
Term
| which cells undergo mitosis in epithelium cells? |
|
Definition
| cells attached to the basement membrane. |
|
|
Term
| how to epithelial cells die when the time comes? |
|
Definition
|
|
Term
| how many zonula occlusens can a cell have? |
|
Definition
| 1. same goes with zonula adherens |
|
|
Term
| What are the four functions of epithelium? |
|
Definition
1. physical protection
2. compartmentalize
3. mediate exchange between biological compartments
4. secretion |
|
|
Term
| what about epithelium makes it protective? |
|
Definition
keratin, multiple layers, desmosomes (these are all things that good strong epithelium will have)
If you are not as concerned with strength, epithelium does not necessarily have to have these things. |
|
|
Term
| in what ways does epithelium compartmentalize? |
|
Definition
| it is a contiuous layer of cells and keeps one compartment from coming in contact with the outside world. |
|
|
Term
| What different ways can epithelium mediate exchange between biological compartments? |
|
Definition
Its structural features (such as tight junctions keep outside substances from just passing by.
1. passive diffusion through the cell (lipids, AA, glucogen, gases)
2. Active transport (ions)
3. Pinocytosis (this method is popular in blood vessels) |
|
|
Term
| What different types of secretions can epithelium be involved with and what materials do they consist of? |
|
Definition
1. serous - watery, thin; contain protein of some sort or another (example: saliva, sweat, etc...)
2. mucous - thick; made of glycoprotein (example: GI tract, nose)
3. lipid - made of lipids (example: lipid/cholesterol based hormones, sabaceous glands, etc...) |
|
|
Term
| What is the difference between the three different types of secretion glands' cell morphology? |
|
Definition
The mucus and lipid secretory cells produce a lot of lipids and carbs so they have very large clearish secretory vessicles. The lipid secretory cell has a lot of ER (much more than the other two). The serous secretory cell has a lot of ribosomes (the mucous cell has ribosomes too) and will be intensely stained do to all of the proteins.
NOTE: lipid secretory cells do not have ribosomes and therefore do not have a lot of ribosomes at all and therefore do not need a large nucleoulus. |
|
|
Term
| what is the difference between exocrine and endocrine glands? |
|
Definition
exocrine are typically released into a duct or a surface of some sort. Endocrine glands are typically released into blood vessels.
NOTE: these only refer to multicellular epithelium. Unicellular are exocrine but do not release into ducts. |
|
|
Term
| What is unique about unicellular secretion cells? What is an example? |
|
Definition
| They are exocrine cells that do not release into ducts. An example is a goblet cell. |
|
|
Term
| What is the name for cells that provide a little extra squeezing to release their ducts contents? |
|
Definition
|
|
Term
| what are the different types of ducts? |
|
Definition
1. simple and compound
2. acinar and tubular |
|
|
Term
| What are the three ways in which secretory cells can secrete their stuff? |
|
Definition
1. merocrine - secretory products are the contents of the secretory vessicles
2. apocrine - secretion of chunks of the cell (most of the cell stays behind) example: some sweat glands)
3. holocrine - the whole cell is what is secreted (example: sabaceous gland) |
|
|
Term
| what is typically found on epithelia that absorb substances? |
|
Definition
|
|
Term
| What is the key to cancer spreading from epithelia? |
|
Definition
| once it finds a way to breach the basement membrane it is gone and it metastesizes. |
|
|
Term
| what do some epithelia have that help it move luminal contents? |
|
Definition
|
|
Term
| what characteristic do some epithelia have that allow it to be efficient transporters? |
|
Definition
|
|
Term
| what are the three different types of planes of section? |
|
Definition
| cross section, oblique section, and longitudinal section |
|
|
Term
| what are the different classifications of epithelium based on 1. layers 2. shape 3. surface specializations? |
|
Definition
1. simple or stratisfied
2. cuboidal or columnar or squamous
3. ciliated or keratinized |
|
|
Term
| what are the functions of squamous cells? |
|
Definition
| material transport and exchange |
|
|
Term
| what are the functions of simple cuboidal and simple columnar epithelia? |
|
Definition
|
|
Term
| what are the functions of ciliated simple columnar and pseudostratisfied columnar epithelia? |
|
Definition
to move contents of the lumen
NOTE: these are the only two types of epithelia that can be ciliated |
|
|
Term
| what is the main purpose of stratisfied epithelia? |
|
Definition
| protect against abrasive forces (dead cells at the top can easily be sloughed off while protecting the live ones. If it is keratinized it can be used for waterproofing too. |
|
|
Term
| What does transitional look like and what is it? |
|
Definition
| it looks like stratisfied squamous when stretched out and looks like stratisfied cuboidal when not stretched. NOTE that there is very few cases where stratisfied cuboidal actually exists so if she shows us a stratisfied cuboidal it will really be transitional. |
|
|
Term
| what are the general components of connective tissue? |
|
Definition
| cells and extracellular matrix |
|
|
Term
| what are the components of the extracellular matrix in CT and what is the types of those components? |
|
Definition
1. Fibers: collagen, elastin
2. Ground Substance: Glycoproteins, Proteoglycans |
|
|
Term
| What predominates in most CT? |
|
Definition
|
|
Term
| What are just some types of connective tissue? |
|
Definition
| CT proper, adipose, cartilage, bone, blood |
|
|
Term
| In what ways does CT act as structural support? |
|
Definition
| packing/cushioning (CTP), tensile strength (tendon/ligament), rigid physical support (bone) |
|
|
Term
| In what ways does connective tissue act as metabolic support? |
|
Definition
| transport (metabolites can travel through CT through diffusion and blood) and storage (adipose) |
|
|
Term
| what are some jobs CT can have? |
|
Definition
| storage, transport, cushion, tensile strength, rigid support, immune response, repair after injury (scars) |
|
|
Term
| what cells are located in CT Proper? |
|
Definition
|
|
Term
| what do fibroblasts look like under both LM and EM? |
|
Definition
| They both make fibroblasts look like squamous cells (accurately described as squamous). Also, they do not really make a lot of proteins and dont have that many organelles so the nucleus is skinny and dark. |
|
|
Term
| What are all of the different types of CT cells? |
|
Definition
| fibroblasts, chondroblasts, chondrocytes, osteoblasts, and osteocytes |
|
|
Term
| What do adipose cells look like and what do they do? |
|
Definition
| they are round and have their nucleus and the rest of their cytoplasm scrunched to the outside of the sphere. It looks like a ring from LM perspective. The adipose cell is typically very clear due to its large number of lipids. The point of the cell is to act as a storage unit of energy in the form of triglyceride. |
|
|
Term
| Where are adipose cells located? |
|
Definition
|
|
Term
| What are some CT cells that act as defense/immune/inflammation cells? |
|
Definition
| macrophage, mast cell, blood cell(lymphocytes, neutrophils, eosinophils) |
|
|
Term
| what is another name for a macrophage? what do macrophages do, what do they look like, and where are they located? |
|
Definition
| It can also be referred to as a histocyte. they phagocytose debris and foreign material. It looks like a large oval under LM but is more ameoba shaped under EM. It typically has a large, oval, clearish nucleus that is very active. The cell looks ameoba'esque because it does move around. It also has a lot of lysozomes. It is most commonly located in CT proper. |
|
|
Term
| what do mast cells do, what do they look like and where are they located? |
|
Definition
| mast cells are involved with allergies (they have no known healthy function). They look like circular cells with prominent dark blue granuals in their cytoplasm (important component: histamine). They have a little darker nucleus and are typically located in CT proper. |
|
|
Term
| What cells in blood act as immune defense? |
|
Definition
| lymphocytes, neutrophils, and eosinophils |
|
|
Term
| What are the different types of fibers in CT and what are their corresponding proteins? |
|
Definition
collagen: collagen
elastic: elastin |
|
|
Term
| What is the most abundant protein in the body? |
|
Definition
| collagen (there are 20 related proteins) |
|
|
Term
| What is the function of the collagen fibers? |
|
Definition
|
|
Term
| Describe the path of collagen from DNA to extracellular full fledged collagen. |
|
Definition
| first the DNA is transcribed to mRNA then the mRNA is translated into preprocollagen protein (which is soluble). After the signal peptides are cleaved modification occurs (hydroxylation, glycosylation) and it forms procollagen (agregated into triple helix). After being modified by the golgi body and shipped to the outside of the cell it immediately is cleaved by extracellular enzymes and becomes tropocollagen. These tropocollagen proteins begin to polymerize because they are now insoluble and form fibrils. Once these fibrils bond together collagen is formed. |
|
|
Term
| what form of collagen along the way does it go from soluble to insoluble? |
|
Definition
| procollagen to tropocollagen |
|
|
Term
| what are the different types of collagen (that we need to know and where are they found? |
|
Definition
1. Type 1 - CT proper, bone, ligaments/tendons, and in fibrous cartilage
2. Type II - cartilage
3. Type III - reticular fibers (found almost everywhere) It is even smaller and it forms an external bracing to individual cells. You can never actually see these.
4. Type IV - basement membrane. It is a linear array so no real thickness.
5. Type VII - lamina propria. It is just as thick as Type II. |
|
|
Term
| What are the function, location, and morphology of elastic fibers? |
|
Definition
function: structural support with stretch and recoil capabilities
locations: skin, bladder, cardiovascular system
morphology: doesnt have any definite shape due to to its elastic characteristic. |
|
|
Term
| what are the components of elastic fibers? |
|
Definition
| elastin (tropoelastin - subunits of elastin) and fibrillin |
|
|
Term
| What is the composition and morphology of ground substance? |
|
Definition
| composition: proteoglycans (and H20) and glycoproteins and ions/minerals. Proteoglycans and glycoproteins form and interconnected web. varies from fluid, gel, and solid. |
|
|
Term
| what are the functions of ground substance? |
|
Definition
1. structural support/space filling (it can add significant rigidity as in the case of bone where the ions add a lot to the strength of the substance)
2. metabolic transport - transport nutrients and metabolites
3. defense - visscosity/solidity is barrier to penetration of foreigh material. |
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Term
| What makes up proteoglycans and glycoproteins? |
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Definition
proteoglycans are made up more of carbs and some proteins (look like bristles)
glycoproteins are made mostly of proteins and have an attached carb. |
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Term
| what is the main goal of proteoglycans? |
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Definition
| it attracts water with its highly charged carb groups. this creates a medium for things to be dissolved and travel through. |
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Term
| What is the term for the carbs that act as 'bristles' on proteoglycans? |
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Definition
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Term
| what are the functions of proteoglycans? |
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Definition
1. bind water - we need water even in bone
2. provide some degree of permeability to that particular ECM - moving nutrients and waste through ECM |
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Term
| what are the different types of proteoglycans and where are they found? |
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Definition
1. Dermatan sulfate - skin, ligament, tendon
2. Chondroitan sulfate - cartilage
3. Heparin sulfate - basement membrane
4. Keratan sulfate - cartilage
5. Hyaluronic acid - 'everywhere' -this does not have the same structure as the others
NOTE: all of these names are named for the GAG molecule |
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Term
| What is the function of glycoprotein? |
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Definition
| to cross-link/bind all the different molecules of the ground substance with each other (proteoglycans, fibers, etc...) and the cell membranes of the CT cells |
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Term
| what are the different types of glycoproteins and where are they found? |
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Definition
1. fibronectin - many types of CT - links/binds CT components and orients collagen fibers
2. laminin - basal lamina - links epithelial cells to basal lamina
3. chondronectin - cartilage - links chondrocytes to Type II collagen
4. Integrins - cell membranes - links cell memmbranes to ECM. |
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Term
| what is the definition of cartilage? |
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Definition
| a semi-rigid form of CT/supporting tissue |
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Term
| What are the functions of cartilage? |
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Definition
1. structural support (ears, nose, ribs, trachea)
2. shock absorption: joints
3. sliding surface of synovial joints: prevents friction
4. growth of bone: epiphyseal plate |
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Term
| Describe the transformation of a chondroblast to a chondrocyte. |
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Definition
| Chondroblast undergoes mitosis and one daughter cell remains a chondroblast while the other starts to become chondrocyte. After mitosis the chondroblast remains a chondroblast as it begins to make fibers and ground substance. Once it becomes full of lipids/carbs for stored fuel and nucleus begins to get smaller, it is referred to as a chondrocyte |
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Term
| what are the different types of fibers in cartilage? |
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Definition
| Type I and II collagen and Elastic |
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Term
| what is in the ground substance of cartilage? |
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Definition
| ORGANIC MATERIALS ONLY: proteoglycans and glycoproteins, NO IONS/MINERALS |
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Term
| How does cartilage present itself throughout the body? |
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Definition
the outer layer is called paricardium. It is composed of dense connective tissue.
the cartilage itself is surrounded by a layer of chondroblasts that are always ready to undergo mitosis.
The next layer is the actual cartilage where chondrocytes exist often in pairs and are located in lacuna. THERE IS NO VASCULATURE IN CARTILAGE. No blood vessels and no nerves. |
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Term
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Definition
| lacuna are the space that chondrocytes live in the cartilage. It does not really exist in live tissue just in preparation for slides when the cells shrink while the cartilage does not. |
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Term
| If the cartilage is completely avascular how do the chondrocytes recieve nutrition? |
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Definition
the diffusion of nutrients to and wastes from the chondrocytes through the ECM in cartilage allows for this to happen. The water attached to the proteoglycans really allows this to happen.
We limit how thick the cartilage can be so that diffusion doesnt have to occur so far
Cells are pretty inactive and have fuel stored up so as to not need that many nutrients and dont need to get rid of that much waste. |
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Term
| What is a major downturn to having avascular cartilacge? |
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Definition
| if it becomes injured it is very hard to repair. |
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Term
| What are the two different types of cartilage growth? |
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Definition
apositional growth - chondroblasts undergo mitosis
interstitial growth - chondrocytes undergo mitosis |
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Term
| How does the chondrocyte know to undergo mitosis? |
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Definition
| growth factor diffuses through the cartilage |
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Term
| What are the three different types of cartilage and what types of collagen exists in each? |
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Definition
hyaline - Type II
elastic - Type II and elastic (can only be seen with a special kind of elastin die)
fibrous - Type I |
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Term
| What are the functions of bone? |
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Definition
1. structural support: a. protection b. weight bearing
2. attachment for muscles via tendons (movement)
3. calcium reserve
4. houses/protects blood forming tissues (bone marrow)
NOTE: it has a specialized CT for rigid structural support |
|
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Term
| describe the process of becoming an osteocyte? |
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Definition
| osteoprogenitor cell (requires growth hormone) to osteoblast to osteocyte |
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Term
| what other types of cells are found in bone? |
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Definition
| osteoclasts (break down bone) |
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Term
| what does a osteocyte and osteoclast look like? |
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Definition
osteocyte: round with projections that help it bind to the ECM. It has a small dark nucleus bc it is mostly inactive and just maintains ECM
osteoclast - multinucleatd (made up of fused macrophages) |
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Term
| what makes up the largest percentage of bone? |
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Definition
| inorganic material (HYDROXAPATITE) |
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Term
| bone has both blood vessels and nerves. T/F |
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Definition
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Term
| Why does bone need cells specifically for breaking down while cartilage does not? |
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Definition
| bone does a lot of remodelling while cartilage does not. |
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Term
| What is unmineralized bone matrix called? |
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Definition
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Term
| What are the basic ingredients of mineralization of bone ECM? |
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Definition
1. collagen
2. calcium and phosphate ions
3. other ECM proteins required to stimulate and inhibit mineralization steps. |
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Term
| What are the basic steps of mineralization? |
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Definition
1. osteoblasts secrete collagen and other ECM proteins into extracellualr region
2. extracellular fluid is supersaturated with Ca and PO4 ions
3. Need 'nucleation sites' among collagen fibrils to initiate mineralization. 2 types: a. osteoblasts form 'matrix vesicles' containing phosphatases and other necessary components for mineralization. THESE BUD OFF CELL INTO ECM. b. Gaps b/n collagen fibrils are filled with ECM proteins which bind CA and PO4
With these two together (a and b) minerals grow between collagen fibrils
4. mineral growth then continues - mineral crystal surround all parts of collagen fibrils (lasts for months) |
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Term
| What are the different types of bone? What are the differences? |
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Definition
Primary and Secondary.
Primary bone is woven and temporary (generally). It is relatively unorganized and less strong. There are more cells in primary bone and not a lot of calcium. Secondary bone is mature bone (lamellar and exists in a rigid organized fashion) |
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Term
| What conditions are primary bone found? |
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Definition
1.embryonic development of bone
2. bone repair (fracture healing)
3. comprises alveolar bone (permanent) |
|
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Term
| what does all bone look like under LM? |
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Definition
| it looks like bland pink substance. |
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Term
| What are the gross anatomic types of bone? |
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Definition
| flat, short, long and irregular |
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Term
| Describe the morphology of long bones? What are the three main regions of long bones? |
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Definition
Periostium surrounds the outer layer
Endosteum covers the inner openings
Cortical bone (compact bone)- exists on outer side underneath the periosteum surrounding the spongy bone
Trabecular bone (spongy bone/cancellous bone) exists in the middle)
Bone marrow exists between the trabeculae
Haversian systems -exists in the compact cortical bone
Articular cartilage exists where the periosteum would normally exist but is on the end of the bone where it forms a joing
Epiphyseal plate exists between the head and neck of bone
THREE MAIN REGIONS:
1. Epiphysis (head)
2. Metaphysis ( imaginary line where epiphysis meets the diaphysis)
3. Diaphysis (skinny neck region of the bone). |
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Term
| what is the job of the trabecular bone? |
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Definition
|
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Term
| Around what region does the bone experience growth? |
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Definition
| epiphyseal plate (metaphysis) |
|
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Term
| what happens to an epiphyseal plate as a person grows and gets older? |
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Definition
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Term
| Describe the morphology of cortical bone? |
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Definition
it is lamellar bone and is also known as compact.
There is an outer circumferential lamellae, osteons (haversian systems), and inner circumferential lamella. |
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Term
| What is the purpose of osteons? |
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Definition
| bear weight of stress. Its lamella are set up to be parallel to lines of stress |
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Term
| What is the vasculature seen in bone? |
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Definition
| in the haversian canals and through the volkmann's canal (sideways) |
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Term
| How are the lamella set up in the ECM? |
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Definition
| Each lamella has collagen set up in the same direction but neighboring lamella are set up perpindicular to each other. |
|
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Term
| how do concentric circles of osteocytes in lacunae interconnect? |
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Definition
|
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Term
| how do canaliculi connect? |
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Definition
| they contain osteocyte processes and they connect via gap junctions |
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Term
| Where do trabecular bone lie? |
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Definition
|
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Term
| what is the purpose of trabecular bone? |
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Definition
|
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Term
| Where do the osteocytes sit in in bone? |
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Definition
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Term
| Where is the ednosteum located? |
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Definition
| lining the innersurfaces of bone |
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Term
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Definition
| single layer of osteoblasts. |
|
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Term
| what happens to the bone marrow cavity as you get older? |
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Definition
| it begins to fill up more with fat than marrow. |
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Term
| What is the periostium? what is its function? |
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Definition
It is a covering of DCT covering the external surface of bones (except at joints)
Its function: muscle insertion (tendon also made of DCT)
and is needed for apositional growth (makes bone thicker) |
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Term
| What is the morphology of the periostium? |
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Definition
| Its outer layer consists of DCT (fibroblasts and collagen) and its inner layer is cellular (osteoprogenitor cells) |
|
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Term
| What are Sharpey's fibers? |
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Definition
| they are DCT penetrations that go from outer layer to inner cellular layer of periosteum |
|
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Term
| Describe the process of bone regineration. |
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Definition
1. osteoclast digests bone
HOWSHIPS LACUNAE - the digested area of osteoclasts but only while the osteoclasts are in them.
2. release Ca and PO4
3. osteoblasts move in
4. synthesize osteoid
5. CaPO4 |
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Term
| Describe bone growth in width. |
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Definition
This is an apositional growth of cortical bone
1. Mitosis of periosteum osteoprogenitor cells and mitosis of endosteum osteoblasts
2. osteoblast synthesize ECM (osteoid)
3. Osteoid is mineralized
4. Periosteum forms new outer circumferential lamellae endosteum forms new inner circumferential lamella |
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Term
| Describe endochondral ossification (increase in length of bone). |
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Definition
1. mitosis of chondrocytes
2. form new layer of cartilage
3. death of these chondrocytes
4. replacement of dead cartilage by bone |
|
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Term
| what kind of cartilage makes up the epiphyseal plate? |
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Definition
|
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Term
| what are the different zones of endochondrial ossification? |
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Definition
1. resting zone: resting hyaline cartilage
2. zone of proliferation: growth factors exists here and is where mitosis of chondrocytes occur
3. Zone of calcification and hypertrophy: Cartilage ECM calcifies and chondrocyte hypertrophies (this calcification prevents the chondrocyte to die.
4. Zone of ossification: (at the endostium) Osteoblasts migrate up the calcified ECM scaffold. Osteoblasts create ostoid that calcifies higher and causes more chondrocytes to die.
5. Remodeling - late stage - Osteoclasts digest calcified cartilage ECM/osteod mixture
Osteoblasts synthesize new bone in response to direction stress |
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Term
| what is another name for the trabecular bone? |
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Definition
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