BDS1 Semester 1 Flashcards
What is the definition of life in terms of physiological functions? (name 8)
- Homeostasis
- Organization (-complexity)
- Metabolism (-obtain and transform energy for growth, reproduction and homeostasis)
- Growth (-accumulation of mass; waste removal)
- Adaptation (-over time/generations)
- Response to stimuli (-often via movement; learning)
- Reproduction
- One more to add to the list… time-limited (senescence and death)
What are the most commonly found atoms that are required for life?(name 6)
Hydrogen, carbon, nitrogen, oxygen, phosphorus and sulfur
Name in order the 6 levels of living functions.
- Cell
- Tissue
- Organ
- Organism
- Community
- Population
Define a functional group.
It is a site of chemical reactivity in a molecule.
Give one example of a functional group.
Amines in proteins
What is a carbonyl group?
Within biology, a carbonyl group within a molecule allows it to undergo the many reactions necessary to maintain life. Many common biological molecules contain a carbonyl group, which allows the cell the ability to create new molecules and modify the molecule with a number of other functional groups.
Example of a carbonyl group.
Aldehyde CH3CHO
What do electrophiles love to associate with?
Electrons
What ions do electrophiles involve?
H+ and Fe3+
What do nucleophiles love to associate with?
Nuclei
What are examples of nucleophiles?
NH3 and OH-
How does carboxylic acids form?
When one of the members on a carbonyl group is OH group, the compound is a carboxylic acids with the generic formula RCO2H
Are fatty acids considered carboxylic acids?
yes
What is the difference between saturated and unsaturated fats?
Saturated fats do not have a carbon-carbon double bond in them.
What compounds are considered dicarboxylic acids?
Compounds that contain two CO2H functional groups are known as dicarboxylic acids
What compounds are considered tricarboxylic acids?
Compounds that contain three CO2H functional groups are known as tricarboxylic acids
What does reaction between a carboxylic acid and alcohols forms?
Ester
What can ester be used for?
Anything from perfumery to local anaesthetics
What are amides?
An amide is a functional group containing a carbonyl group linked to a nitrogen atom or any compound containing the amide functional group. Amides are derived from carboxylic acid and an amine. Amide is also the name for the inorganic anion NH2.
What are amines?
Amines are formally derivatives of ammonia, wherein one or more hydrogen atoms have been replaced by a substituent such as an alkyl or aryl group (these may respectively be called alkylamines and arylamines; amines in which both types of substituent are attached to one nitrogen atom may be called alkylarylamines).
What are cyclic amides called?
Lactams
What is a fornix?
The fornix is the area where the mucosa of our lips/cheeks and mucosa covering the bone surrounding our tooth roots meet.
What is the oral cavity divided into?
The vestibule and the oral cavity proper
What is buccal side?
Side that is closer to the lips for pre-molars and molars.
What does FDI stand for?
Federtion dentale internationale
What are the adult teeth called?
Permanent dentition
What are the baby teeth called?
Deciduous dentition
How many teeth does and adult have
28 (7 in each quadrant) plus 1, 2, 3 or 4 wisdom teeth (3rd molars)
What does occlusal mean?
It’s the surface on the top of molars and pre-molar teeth
What does incisal mean?
it’s the surface on the tops of incisors and canines
What does labial mean?
Surface closest to the cheeks for incisors and canines
What does lingual mean?
Surface closest to the tongue
What does mesial mean?
Surface that is facing the imaginary midline in the quadrants
What does distal mean?
Surface that is facing away from the midline
What is a groove?
a groove is a shallow linear depression
What is a groove?
a groove is a shallow linear depression seen on the first premolar for example
What is a pit?
A pit is a small pinpoint depression seen for example on the first molar
What is a ridge?
A linear elavation
What is a fossa?
A rounder or angular depression seen on the second pre-molar for example
What is the name of the bone that holds teeth together?
Alveolus
What is a frenum?
a small fold or ridge of tissue which supports or checks the motion of the part to which it is attached, in particular a fold of skin beneath the tongue, or between the lip and the gum.
What is a glucan?
a polysaccharide consisting of glucose units.
What are monosaccharides?
any of the class of sugars (e.g. glucose) that cannot be hydrolysed to give a simpler sugar.
What are disaccharides?
any of a class of sugars whose molecules contain two monosaccharide residues.
What are oligosaccharides?
a carbohydrate whose molecules are composed of a relatively small number of monosaccharide units
What are polysaccharides?
a carbohydrate (e.g. starch, cellulose, or glycogen) whose molecules consist of a number of sugar molecules bonded together.
How are amino sugars formed?
OH is replaced with an amino group
How are deoxysugars formed?
OH group replaced at C6 with H
How are acid sugars formed?
The sugar acids are obtained when a carbonyl group or a hydroxyl group is oxidized to a carboxylic acid group
What does hydrolysed mean?
It means that water was used to break down the chemical bond
What are homopolysaccharides?
They are polysaccharides that contain a single monosaccharide unit
What are heteropolysaccharides?
They are polysaccharides that contain two or more monosaccharides
What is cellulose?
It is a fibrous water insoluble linear unbranched homo-polysaccharide main constituent of wood and cotton
What are the four classes of teeth?
Incisor, canine, premolar and molar
What do we call the upper jaw?
Maxilla (or maxillary jaw)
What do we call the lower jaw?
Mandibule (or mandibular jaw)
What is an important aspect of tooth identification?
Multiple features of the tooth need to be considered, no single feature is definitive
What are the key features of permanent incisors? (name 3)
Trapezoidal view from labial side, triangular from proximal, single root
What is the main difference between the central and lateral maxillary incisors?
Central is usually larger and longer then the lateral
What it the difference between the central and lateral mandibular incisors?
Central is usually smaller and more like a trapezium while lateral is larger and has aslight slunt
What are the distinctive properties of maxillary canines?
Bell shaped from labial side and M shaped cingulum with a triangular lingual ridge
What are the features of the mandibular canines?
The miseal surface if flat and the cingulum and marginal ridges are not not as distinct
What are the features of the first upper premolars? (name 5)
Buccal cusp peak, a central grove, distolingual surface is more defined (think a defined jawline), triangular fossa situated on towards the distal side, mesial developmental depression (also known as canine fossa)
What are the features of second upper premolar? (Name 3)
The shape is sually smaller and less triangular looking from the buccal side then first premolar, many supplemental grooves, no mesial developmental depression
What is a possible alternation relating to the roots of upper first and second pre-molars?
They may have 2 roots
What are the features of first and second mandibular molars? (name 3)
Rectangular occlusal outline, 4-5 cusps with paletal cusps being the tallest, two roots
What are the features of first upper molars?
Larger then second upper molars, carabelli trait sometimes, 4 cusps, long central depression
What are the features of second upper molars?
Smaller then the first upper molars, Hot cross bun shape, less sharp cusps
What are electrolytes?
Compounds that produce ions when dissolved in water
What are ions?
An ion is a charged atom or molecule. It is charged because the number of electrons do not equal the number of protons in the atom or molecule. An atom can acquire a positive charge or a negative charge depending on whether the number of electrons in an atom is greater or less then the number of protons in the atom.
What are acids?
Acids are electrolytes that can donate H+ ions in water solution
How do we define a strong acid?
We define a strong acid by its dissociation constant.
What is a dissociation constant?
The dissociation constant, or Ka, is the ratio of ions to acid. It is determined by comparing the concentration of product to reactants once a reaction reaches equilibrium.
What determines a base strength?
An ability of a base to ionise and produce hydroxine ions (OH-)
What do pH buffers do?
pH buffers remove acid or base ions from the environment so pH charges are minimised
what are triacyl glycerols?
Triacylglycerols, also known as triglycerides, are the simplest lipids formed by fatty acids. It is made up of three fatty acids ester linked to a single glycerol. Most triacylglycerols contain two or three different fatty acids. Triacylglycerols are nonpolar, hydrophobic, and insoluble in water.
What are phospholipids?
A phospholipid is a type of lipid molecule that is the main component of the cell membrane. Lipids are molecules that include fats, waxes, and some vitamins, among others. Each phospholipid is made up of two fatty acids, a phosphate group, and a glycerol molecule.
What are sphingolipids?
any of a class of compounds which are fatty acid derivatives of sphingosine and occur chiefly in the cell membranes of the brain and nervous tissue.
What are enzymes?
Enzymes are biological molecules (typically proteins) that significantly speed up the rate of virtually all of the chemical reactions that take place within cells. They are vital for life and serve a wide range of important functions in the body, such as aiding in digestion and metabolism.
What is the prosthetic group?
a non-protein group forming part of or combined with a protein.
What is an apoenzyme?
An apoenzyme is an inactive enzyme, activation of the enzyme occurs upon binding of an organic or inorganic cofactor.
What is a holoenzyme?
a biochemically active compound formed by the combination of an enzyme with a coenzyme.
What is are saturation kinetics?
he kinetics of a reaction (or of mediated transport) when the velocity of the reaction (or of the transport) increases to a maximal value (plateau) as the concentration of the reactant (or of a component being transported) is increased.
What is a peroxisome?
a small organelle present in the cytoplasm of many cells, which contains the reducing enzyme catalase and usually some oxidases
What are the 3 main types of fibres in the cell?
Microtubules, intermediate filaments, microfilaments
What are microfilaments composed of?
Composed of actin proteins
What are the main functions of microfilaments?
Cell shape/rigidity, cell division, phagocytosis
What is the function of microtubules?
transport of structure within the cell
What are microtubules composed of?
Tubulin
What are intermediate filaments made of?
Different proteins unlike microfilaments and microtubules
What is a microvilli?
Microvilli (singular: microvillus) are microscopic cellular membrane protrusions that increase the surface area for diffusion and minimize any increase in volume, and are involved in a wide variety of functions, including absorption, secretion, cellular adhesion, and mechanotransduction.
What is the main function of microvilli?
Increase the surface area of cell membrane
What is a cilia?
a short microscopic hairlike vibrating structure found in large numbers on the surface of certain cells, either causing currents in the surrounding fluid, or, in some protozoans and other small organisms, providing propulsion.
What is a function of a tight junction?
Seals neighbouring cells together in an epithelial sheet to prevent leakage of molecules between them
What is a function of adherens junction?
Joins an actin bundle in one cell to a similar bundle in a neighbouring cell
What is the function of desmosome?
Joins the intermediate filaments in one cell to those in a neighbor
What is a function of a gap junction?
Allows the passage of small
What is a function of hemidesmosome?
Anchor intermediate filaments in a cell to the basal lamina
How do we distinguish between right and left central maxillary incisor?
The mesioincisal angle
How do we distinguish between central and later maxillary central incisors?
Lateral inscisors are smaller and have marginal (side ridges) more prominent than central ridge
How do we distinguish central incisors on the mandible from lateral incisors on the mandible?
Central incisors are symmetrical while lateral incisors have mesioincisal angle towards the mid line
How do we distinguish between between a 13 and 43
A 43 has a less distinct cingulum
What is H&E staining?
H&E staining. The most commonly used staining system is called H&E (Haemotoxylin and Eosin). H&Ec contains the two dyes haemotoxylin and eosin. Eosin is an acidic dye: it is negatively charged (general formula for acidic dyes is: Na+dye-). It stains basic (or acidophilic) structures red or pink. Haemotoxylin is a base: it is positively charged and stains acid structures blue or purple.
Why is pH is important in dentistry?
Changes in pH may result to irreversible damage to the teeth
What is the critical pH?
5.5
What is a fluid in yoru body that needs to be maintained within a narrow pH range?
Blood ( should be near nuetral)
What produces acid in the mouth?
Bacteria
What are the 3 major factors that may cause a dis balance in mouth pH levels?
Bacterial metabolism, gastric reflux and diet
How do we maintain pH stability in the mouth?
By use of saliva (pH buffering)
What does the measurement of pH indicate?
Proton concentration
What is pH buffer?
A pH buffer is a structures that allows to reduce the fluctuation of pH within an environment
What is an electrolyte?
It is a compound that produces ions when dissolved in water
What is a strong electrolyte?
A strong electrolyte are substances that completely ionise to make ions in water
What is a weak electrolyte?
Weak electrolytes dissolve in water to produce a mixture of ions and molecules.
What does H+ actually stand for?
H3O+ because H+ does not exist in nature for a long time thus associates with water
What does Ka stand for?
Ka is a dissociation constant
When a solution goes above pH of 7, it becomes….?
Basic
How to calculate the pH?
1 x 10 ^-pH
What are the 3 indicators of good oral health?
- pH of resting saliva
- The amount of saliva produced
- Buffering capacity of sliva
What does a buffer contain?
•A buffer usually contains two substances, a weak acid or weak base
and its salt.
What weak acid does saliva contain?
Carbonic acid (works with pH above 7.3)
What ion is used in saliva to buffer the pH?
Bicarbonate ion (works with pH above 7.3)
What is the best way to normalise the pH of the oral environment after eating or drinking something acidic?
Chew gum. Gum will trigger the production of saliva which will increase the amount of bicarbonate ions thus reducing the number of hyronium ions.
What does pKa measure?
pKa measures the strength of the weak acid/ weak base.
What is pKa?
pKa is the pH at which an acid is 50% dissociated.
What is the most abundant molecule in nature?
A carbohydrate
What does polyhydroxyl mean?
containing more than one hydroxyl group in the molecule.
What is a monosaccharide?
They are simple sugars conataining aldehyde or ketone. Examples Glucose and Fructose.
What is a disaccharides ?
A molecule with 2 monosaccharides units, example Surcose.
What are oligosaccharides?
A molecule with 3 or more monosaccharide units.
What are polysaccharides?
A molecule with 100s - 1000s monosaccharide units. They are branched. Example starch.
What does the prefix+ose stand for in carbons?
Prefix stands for the number of carbons present in the molecule.
What is an O-Glycosidic bond?
Bond that forms in disaccharides like sucrose, lactose etc.
What is homopolysaccharide?
It is a polysaccharide molecule that contains a single monosaccharide unit.
What is a heteropolysaccharide?
It is polysaccharide that contains two or more monosaccharide units.
Why is coiling of polymers important?
It allows for more efficient conversion of polymers into monosaccharides?
What is a part of bacterial cell walls?
Heteropollysaccharide of altering beta (1 to 4)
What is EM (extracellular matrix comprised of)
Fibrous proteins and a meshwork of Heteropolysaccharides
What is hyaluronic acid made out of?
Repeating units of glucoronic acid and N-acetylglucosamine
What are proteoglycans?
Proteoglycans are usually hyaluronic acid attached to extracellular protein/carbohydrate molecule call aggrecans.
What is one function of glycoproteins?
They can be used on the surface of the cell membrane as carrier proteins.
What are the 5 steps of identifying a tooth?
- class 2. jaw 3. dentition 4. series 5.side (e.g. incisor, maxillary, permanent, central, right)
What are the features of permanent incisors?
- Trapezoidal from labial. 2. Triangular from proximal. 3. Flat incisal edge for cutting. 4. single root
What is the difference between the maxillary and mandibular permanent incisors?
Maxillary incisors are usually larger, the roots are more rounded, central incisor is usually longer then the later incisor
What are the key features of maxillary canines?
Bell shape, distinct cingulum, lingual ridge.
What are the key features of mandibular canines?
Flat mesial surface and less distinct cingulum & marginal ridges.
What are the key features of upper first pre-molars?
2 cusps, central grove, supplemental grooves, mesial developmental groove, hexagonal occlusal outline, mesial developmental depression, 2 roots, buccal cusp is taller.
What are the key features of upper second pre-molar?
2 cusps, central groove (less distinct), single root, more supplemental grooves, cusps are nearly equal in height, quite round.
What are the key features of lower first pre-molar?
MLI developmental groove, transverse ridge, single root, 45 degree tilt, transverse ridge
What are the key features of the lower second pre-molar?
Variable occlusal with either U-shape (2 cusps) or Y-shape (3 cusps), no tilt
What are the key features of first upper molars?
Rhomboidal shape, oblique ridge, 4 cusps (larger on the buccal side), sometimes cusp of carabelli, 3 roots
What are the key features of the mandibular first molar?
Rectangular in shape, 5 cusps, taller lingual cusps, central groove
What are the key features of the mandibular second permanent molar?
Cross shape, 4 cusps,
What are the key features of the maxillary second molar?
Smaller then first molar, rounded
What determines the function of a protein?
It’s unique 3D structure
What is the blueprint for a protein?
DNA
How many genes are there?
About 20 thousand
How many amino acids are there?
About 20
What makes up an amino acid?
A central carbon, a hydrogen atom, carboxyl group, an amine group and an R group
What do amino acids make good buffers?
Due to the fact that they can lose a hydrogen atom or absorb a hydrogen atom (amino acids make up the protein component of 3 stage saliva buffering theory).
What is the key feature of aromatic amino acid?
It is non-polar thus does not associate well with water (oil into water affect)
What is the general trend associated with increasing the number of hydro-carbon chains in a molecule?
Increasing the number of hydro-carbon chains results in decrease in water solubility
Why is post-translation-modification important to sustain life?
Post-transnational modification allows to modify proteins post translation thus allowing to change said proteins making them more specialised thus more efficient in certain situations (lead to non-standard amino acids).
What is a peptide bond?
A peptide bond is a strong covalent bond that formed between amino acids by amide linkages.
What are the four structures of proteins?
Primary, secondary, tertiary, quaternary
Why is a fatty acid called a fatty acid?
Because it contains a carboxylic acid group
What is an amphipathic molecule?
A molecule that contains both hydrophilic and hydrophobic components
What is a key feature of a saturated fat?
It doesn’t have any double bonds thus it is linear and is a solid at room temperature
What is a key feature of unsaturated fat?
It has a double bond in it and is a liquid at room temperature
Where is the double bond located in the omega-3 fatty acid?
It is located 3 hydro-carbon chains from the omega ( or the last) hydro-carbon.
Why is it a problem for our body to store amphipathic molecules of fat?
Our body wants a relatively non-polar molecule that will allow for storage in the tissue of the body thus the hydrophilic components need to be removed.
What does the body do to neutralise fatty acid?
Connect them with glycerol and create triaglycerol and store them.
What are the three types of lipids found in our body?
Storage lipids, phospholipids and sphingolipids
What is the function of phospholipids in our body?
Create micelles
What are some of the functions of sphingolipids?
They are also present in cell membranes and also help to determine blood types (due to the sugars that their tail contains)
What is good cholesterol and what is bad cholesterol?
Good cholesterol is the high density one, bad cholesterol is the low density one.
What are nuclei acid made out of?
Nucleic acids are made out of monomers called nucleotides
What are the 2 primary forms of nucleic acids?
RNA and DNA
What are the three core components of a nucleotide?
- Five carbon (pentose) sugar. 2. Phosphate group. 3. Nitrogenous base.
Classify the important carbons within a carbon ring structure of a nucleic acid and define it’s function.
1’ carbon - bound to nitrogenous base
2’ carbon - gives nucleic acid it’s name depending on presence / absence of OH group
3’ and 5’ carbons - bound to phosphate groups associated with conditionality of linear macromolecules.
What are the two “flavours” of nitrogenous bases?
Purines (A and G) and pyrimidines (C, T, U)
What are the two primary functions of nucleic acids?
- Encode information for protein synthesis
2. Can be copied with high-fidelity
What are the four functions of RNA (hint think names)?
mRNA, tRNA, rRNA and miRNA
What are two main functions of DNA?
Acts as a template for creating RNA and template for creating new DNA
What are the two important processes that are associated with enzymes that are essentially there objectives?
- Hold molecules close together. 2. Have molecules in the correct orientation.
What are the two objects that sometimes need to bind to the protein component to create an active enzyme?
Co-factors ( e.g. ions) and co-enzymes (e.g. FAD)
What is the active form of an enzyme called?
Holoenzyme
What it he inactive form of an enzyme called?
Apoenzyme
What is activation energy?
The minimum quantity of energy which the reacting species must possess in order to undergo a specified reaction.
What is the primary function of enzymes?
To reduce the activation energy
What does weak non covalent bonding produce for an enzyme?
It produces enzyme specificity
What is a transitional state?
A transitional state is a moment at which maximum energy is applied on a substrate
What does low K(m) mean?
High affinity
What are the two types of cells?
Prokaryotes an eukaryotes
What are the 4 common components in all cells?
- Membrane bound
- Cytoplasm/ cytosol
- Genetic material - DNA
- Organelle - ribosomes
What is the nuclear envelope?
Nuclear envelope is the double membrane that surrounds the nucleus.
Describe chromatin
It is the material that makes up the chromosomes both when condensed and decondensed
What is the nucleolus?
Nucleolus is the dark area in the middle of the cell, it is the site of ribosome biogenesis in eukaryotic cells.
What is he light part of chromatin in the nucleus?
It is non-tightly bound euchromatin (genetic material is available for protein synthesis)
What is the dark apart of chromatin in the nucleus?
It is tightly bound heterochromatin (genetic material is not available for protein synthesis)
What are the inclusions within a cell?
They could be inert structures, cell products and materials that nor organelles nor active in metabolism.
What it the structure of a ribosome?
Large subunit on top of a smaller subunit, made out of protein
Is a ribosome basophilic ?
Yes
What is a golgi body used for?
Creation of vesicles for export, modification of protein, carbohydrate synthesis, lysosome production
What are the two faces of a vesicle?
Immature and mature face
What are the functions of lysosomes?
Used for digestion of foreign substances (e.g. bacteria), autophagy, autolysis hydrolysis
What is role of mitochondria?
Conversion of ADP into ATP and conversion of ATP into ADP
Why does mitochondria have a folded membrane?
Increased surface area equals more interaction
What are the five distinct spaces in mitochondria?
- Outer mitochondrial membrane. 2. Intermembrane space 3. Inner mitochonrial membrane. 4. Cristae spcae. 5. Matrix
What are the three parts that make up the cytoskeleton?
- microtubules
- microfilaments / actin filaments
- intermediate filaments
What are the functions of the cytoskeleton?
- cell shape
- cell movement
- cell structure
- organelle & vesicle movement
- cell division
Where do you find the microfilaments?
Around the boundary of the cell.
Where do you find the intermediate filaments?
In the middle of the cell
Where do you find the microtubules?
They form the spindal aparatus
What are the functions of microfilaments?
Cell shape, mechanical support (microvilli), cell movement, phagocytosis, cell division
What are the functions of microtubules?
Transport of organelles, make up centrioles and cilia
What are the functions of intermediate filaments?
Structure, anchorage, support of junctions between cells
What are microvilli used for?
Increase surface area
What is cilia?
Cilia is a hair like structure that help by physically pushing material like mucus
What are the four types of junctions?
- Tight Junction 2. Zonula adherens 3. Desmosomes 4. Hemidesmosomes
What are the functions of a tight junction?
Seals neighboring cells together in an epithelial sheet to prevent leakage of molecules between them
What are the functions of a adherens junction?
Joins an actin bundle in one cell to a similar bundle in a neighboring cell
What are the functions of a desmosome?
Joins the intermediate filaments in one cell to those in a neighbor
What are the functions of a gap junction?
Allows the passage of small water-soluble ions and molecules
What are the functions of a hemidesosome?
Anchors intermediate filaments in a cell to the basal lamina
What are the three divisions of endocytosis?
- Phagocytosis 2. Pinocytosis 3. Potocytosis
What is the current membrane model?
Fluid mosaic model
How can we describe the rate of influx of substrate when talking about simple diffusion?
It is linear
How can we describe the rate of influx of substrate when talking about facilitated diffusion?
It has a curvature and has a maximum rate.
What are the two types of active transporter?
Primary with use of ATP and secondary with use of Na+ gradients
Why are ion channels important?
Without ion channels there would be no electrical signalling.
What are the four main classes of ion channels?
K+ channels, NA+ channels, Ca2+ channels and Cl- channels.
For 1.1 and 2.1 what is the key curvature feature?
There is a mesioincisal 90 degree angle, triangular from distal and mesial views
What is the key feature of mesial / distal view of 1.2 2.2?
It is more triangular and smaller then 1.1/2.1
What are the key features of lower central incisors?
More cematrical on both sides, mesial edge is upright and is curved triangle shape from mesial/distal view
What are the key features of lower lateral incisors?
Not symmetrical, trapezoidal in shape
What are the key features of the upper canines from the R/L side?
Steeper slope from the distal view then mesial
What are the key features of the lowr canines from the R/L side?
Steeper slope from the distal view then mesial
What are the key features of the upper pre-molars from the R/L side?
Find the mesial developmental groove, indicated the 1st pre-molar and mesial side
What image can be seen on the light microscope?
Usually the purple stained image
What image can be seen on the TEM?
Usually black and white image
What image can be seen on SEM?
Usually very high quality image
How can we identify foreign bodies in polarising microscopy?
Usually are shown as crystals or empty spaces
What is the most common staining?
H&E staining
Distinguish acidophilic and basophilic dyes.
Basic dyes are acidophilic and colour thing in blue (things like DNA), acid dyes are basophilic and colour things in pinkish, magenta colour (things like protein).
What is the difference between LM and EM?
EM has greater resolving power
Cell polarity is…
the differential & asymmetric organisation of cellular components
What are the five functions that require cell polarity?
- Cell adhesion/ barrier or communication. 2. Concentration of ions across the cell. 3. Efficient absorption. 4. Movement/fluid current flow. 5. Protein synthesis.
What are the three surfaces that can be associated with a cell?
Apical, basal and lateral.
What are the 8 potential examples of some of the human nucleus types?
Spherical, ovoid, lobulated, segmented, Kidney bean shaped, elongated, condensed, polyploid.
What is one advantage and one disadvantage of lobulation?
Advantage: lobulated white blood cells are able to fit in tight spaces. Disadvantage: cells are more susceptible to damage.
What is a fusiform cell?
They are spindle-shaped cell, example smooth muscle cells.
What are the two types of cell death?
Apoptosis (programmed) and necrosis (accidental)
List the steps of apoptosis and describe them
- Pyknosis (DNA condenses into shrunken basophilic mass) 2. Karyorrhexis ( Nucleus fragmentation. 3. Karyolysis (nuclear fading)
What is the main difference in results of apoptosis and necrosis?
Apoptosis results in multiple membrane bound apoptotic bodies and the insides are never released, while necrosis is basically just a release of organelles.
What are the 4 primary tissue?
- Muscle tissue
- Nervous tissue
- The epithelium
- Connective tissue
What is a tissue?
A tissue is a group of cell organised to perform one (or more) specific functions.
What are the morphological characteristics of epithelium cells?
Epithelium = covers & lines, forms glands:
Shape of cells
Number of cell layers
Specialisation at tissue surface.
What are the morphological characteristics of connective tissue?
Connective tissue = underlines & supports:
Type of cells
Type of arrangment of fibres
Relative proportions of cells, fibres & AGS.
What are the morphological characteristics of muscle tissue?
Ability of cells to contract
Contractile proteins present - actin & myosin
What are the morphological characteristics of nervous tissue?
Exhibit electrical properties
Ability to receive, transmit & intergrate electrical impulses
Non-excitable supporting cells = neuroglia
What are the five characteristics of epithelial tissue?
- Highly cellular
- One free surface
- Basal lamina
- Avascular
- Dynamic
What are the sub-types of epithelial tissue?
Surface epithelium and glandular epithelium
Characteristics of connective tissue.
- range of cell types
- Abundat extracellular material
- Highly vascular
- CDPST function
Characteristic of muscle tissue.
- Contractile
2. 3 subtypes: skeletal, cardiac, smooth.
Characteristics of nervous tissue.
- Composed of neurons & neurogila
2. Monitoring and responding
What are the three layers of trilaminar embryo?
Ectoderm, mesoderm and endoderm.
Ectoderm can produce…
Nervous tissue and epithelium tissue
Mesoderm can produce…
Connective tissue, muscle tissue and epithelial tissue
Endoderm can produce…
epithelium
What is the cutaneous membrane?
Composed of stratified squamous epithelium, underlying CT containing epithelial derivatives. Basically skin
What are the two epithelial membranes?
Mucosa and serosa
Features of mucosa.
- Lines cavities connected to outside.
2. Surface epithelium,basement membrane, supporting CT +/- glands, smooth muscle
Features of serosa.
- Lines internal body cavities.
2. Mesothelium, basement membrane & supporting CT.
What is a synovial membrane?
It is a connective tissue membrane that lines capsules of synovial joints. Produces lubricant.
What composes microfilaments?
Mostly actin
What composes microtubules?
tubulin
What composes intermediate filament?
Many different proteins
What is fibronectin?
Fibronectin is a protein that is involved in a number of functions like connective tissue etc.
What are the 5 characteristics of epithelial tissue?
- Highly cellular 2. Forms sheets or layers 3. Basal lamina 4. Avascular 5. Dynamic
What are the 4 functions of surface epithelium?
- Barrier 2. Secretion 3. Absorption 4. Bidirectional transportation
What are the clusters of glandular epithelial cells are called?
Acini
What are the two types of glands?
Exocrine and endocrine glands
What are the three components of cell to cell adhesion?
- Adhering junctions 2. Tight junctions 3. Communicating junctions
Where does basal lamina lay?
It lies at the interface between epithelial cells & adjacent connective tissue.
Where else can we see the basal lamina?
Between muscle cells & CT, nervous tissue & CT.
What are the three functions of basal lamina?
- Filter 2. Fence 3. Frame
What are the three shapes of epithelial cells?
- Squamous 2. Cubiodal 3. Columnar
What does keratinised cell mean?
It means that the cell is dead
What is metaplasia?
Transformation of one type of epithelium into another via replacement of one differentiated cell type with another mature differentiated cell type normally present in the tissue.
What are the three components of CT?
1.Cells 2, AGS 3. Fibres
How do we classify the CT?
- Proportions of cell to fibres to AGS. 2. Organisation/orientation of fibres.
What does mesechyme give rise to?
CT cells and stem blood cells
What are the three types of fibres?
Collagen, elastic & reticular
What types of cell are present in CT?
- Structural cells (fibroblasts for creation and adipocytes for storage) 2. Immature cells (ECM) 3. Mature cells (all the cytes)
What defensive cells are there?
Macrophages, mast cells, plasma cells, lymphocytes, neutrophils & eosinophils.
What are the two key observations about AGS?
- Located between cells & fibres. 2. Functions to provide medium for substance exchange.
What are the variations of AGS?
- Fluid (Blood) 2. Semifluid (Cartilage) 3. Gelatinous (loose and dense CT) 4. Hard (Bone)
What is collagen used for?
Strength (Thick looking fibrils, banded)
What are reticular fibres used for?
Net-like network for cells
What are elastic fibres used for?
Elasticity (not as thick and not banded)
What are the 3 roles of fibres?
- Connecting and binding tissues & organs & transmitting force. 2. Giving support shape and flaxibility 3. Protection
What are the three roles of cells?
- Store energy and act as insulation. 2. Protect the body from infections
What is the role of AGS?
Transport nutrient/waste products between blood & epithelium.
What are the two types of connective tissue?
Loose CT (more AGS then fibres) and dense CT (more fibres then AGS)
What are the two types of dense CT?
Dense regular (fibres run parallel), dense irregular (fibres run in different direction)
What is progression complexity related to collagen family protein?
Fibrils to fibres to fibre bundles.
What are the three types of collagen?
Fibrillar collagens, network or sheet forming collagens, linking & anchoring collagens.
What cell creates collagen?
Fibroblasts
What is a illongate nucleus that can be sometimes found in collagen?
It is a fibrocyte, a cell that before was a fibroblast that created this collagen fibre
How are reticular fibres represented?
Tiny koonts
What are elastic fibres formed from?
elastine
What do they look like?
Branched and long
Where is elasin prominant?
Aorta
What is AGS composed of?
Protein and carbohydrate components
Where do fat cells originate from?
They arise from mesenchymal cells during period from late fetus to aprrox. 15 months
Where do macrophages arise from?
Monocytes
What are the key features of macrophages?
- Pseudopodia 2. Phagosomes 3. Lysosomes 4. Residual bodies 5. RER 6. Microtubules
What is a distinct feature of a plasma cell?
It looks like a clock.
Role of mast cell?
Need special staining for mast cells. Storage of chemical mediators of infalmatory response. Allergy reactions.
What are the three types of leukocytes?
Lymphocytes, neutrophils, eosinophils.
How do we separate secretory cells?
They are either endocrine, exocrine, unicellular or multicellular
Explain the development of exocrine glands?
Invagination of epithelial cells, further differentiation, creation of a duct
What is an acinus?
Cluster of secretory cells
What are the two types of secretion produced by acini cells?
Mucous acini and serous acini
What are the three types of secretion?
Merocrine (only secretion), apocrine (secretion and some cytoplasm (mammary gland)), holocrine (entire cell becomes secretion (sebaceaous glands))
What are the myoepithelial cells?
Basiclally muscle like sells that surround galnds and contract
What is the main difference between mucosa and serosa?
Mucosa line the cavities which are in contact with outside environment, serosa line the organs.
What 2 tissue types make up the mucosa?
Innermost surface epithelium & underlying loose connective tissue
What are the three types of serosa?
- Parietal peritoneum 2. Masentery 3. viseral peritoneum
What are the three layers of skin?
Epidermis, dermis and hypodermis
What are the two types of skin?
Thin skin (the most common) and thiiiiiiiiccc skin (covers palms and soles)
Describe epidermis.
Stratified squamous keratinised epithelium, no blood vessels
What is the main cell type in the epidermis?
Keratinocyte
Name the layers of the epidermis starting from the bottom to the top.
- Stratum basale 2. Stratum spinosum 3. Stratum granulosum 4. Stratum corneum
What are the key features of stratum basale?
- Keratinocytes on basement membrane 2. Desmosomes between kearatinocytes. 3, Hemidesmosomes adhere cell to dermis 4. Cytokeratins appear
What are the key features of stratum spinosum?
- Cells begin to flatten 2. Accumulate keratin 3. Narrow gaps present between keratinocytes 4. Cytoplasmic extensions snap gaps & are joined by desmosomes
What are the key features of stratum granulosum?
- Granular layer (water proofing) 2. Keratinocytes die
What is the key feature of stratum corneum?
It is dead
What are melanocytes?
They are cells that produce melanin, they are present in the basal layer and go between keratinocytes.
What are the langerhans cells?
They are cells that differentiate from the monocytes, they are a type of macrophage, have a role in inflamitory response for example dermatitis
Epidermal ridge?
When epidermis goes into the dermis
Dermal papila?
When dermis goes into epidermis
What are the two layers of the dermis?
Papillary layer (Loose Ct, fine elastic fibres & collagen) and reticular layer (dense irregular CT, withstands stress in all direction)
Difference between eccrine and apocrine sweat glands?
Eccrine is just regular and apocrine relate to hair follicles
What is arrector pili muscle & sebaceous glands?
Arrector pili muscle make the hair follicles go upright and sebaceous glands secrete the lubricant.
What is the cutaneous plaxus?
A layer of blood vessels that is present in the dermis and hypodermis junction
What is the sub-papillary plexus?
A layer of blood vessels that runs between papillary & reticular layers.
What are the three models of the Dentist-Patient relationship?
Paternalism, consumerism, Mutual / Collaborative
What do we mean by matrix?
Matrix - intercellular components are firm, resist deformation
What do we mean by lacuna?
Hollow spaces in the matrix in which cell reside.
What cells are related to cartilage?
Chondrocytes (they create matrix)
What collagen type is used for crtilage?
Type 2
What is perichondrium?
Dense irregular CT that envelopes the cartilage
What are the two types of growth o fht ecartilage?
Interstitial growth (matrix growth) and appositional growth (new layer of perichondrium)
What are the three types of cartilage?
Hyaline, elastic, fibrocartilage
What are the osteoblasts?
Bone forming cells
What are osteocytes?
Cells that maintain matrix
What are the oseoclasts?
bone resorbing cells
What are the three layers of the mucosa?
Wpithelium, lamina propria, muscularis mucosa
What are the three types of oral mucosa?
Masticatory mucosa, lining mucosa, specialised mucosa.
What are the two types of keratinasation?
Orthokeratinisation and parakeratinisation
What make up NS?
brain, spinal cord, nerves ganglia
What are the functional divisions of the nervous system?
Somatic nervous system, autonomic nervous system, enteric nervous system
What is the amount of neurons and the glial cells in hour nervous system?
10% is comprised of neurons, 90% is comprised of glial cells
What neuron is used as a sennsory object?
Unipolar
What neuron is used in the eye retina?
Bipolar
What neuron is used as a motor neuron and interneuron?
Multipolar
What are the foru types of glia cells in the central nervous system?
- Ependynal cells 2. Microglia 3. Oligodendrocytes 4. Astrocytes
What is the ependymal cell?
It is a cell that forms the ependyma, it is a simple columnar epithelium with cilia and it produces cerebrospinal fluid (CSF)
What is the microglia in brain?
It is a cell that forms monocytes in blood, phagocytic cells, it continuesley surveys CNS environment.
What is the oligodendrocyte?
Provides myclin in CNS
What is an astrocyte?
It is a star shaped cell, utilised for numerous cellular processes, it creats a blood brain barrir.
What is the BBB?
BBB is the blood brain barrier and it allows for the brain to be separated from the blood in order to create better regulation
What are the three layers of the meninges?
Dura mater, arachnoid mater, pia mater
What does CSF do?
While the primary function of CSF is to cushion the brain within the skull and serve as a shock absorber for the central nervous system, CSF also circulates nutrients and chemicals filtered from the blood and removes waste products from the brain.
Grey matter is mostly composed of?
Neuron cell bodies
White matter is composed of?
Axons
What is the fast pain axon?
A delta - myclinated axon
What is the slow pain axon?
C - unmyelinated axon
What are the three basic muscle types?
- Skeletal 2. Cardiac 3. Smooth muscle
What are myocytes?
They are muscle fibers
What are sacolemma?
Muscle cell membrane
What is sacoplasm?
It is the muscle cell cytoplasm
Ligaments attach?
Bone to bone
Tendons attach?
Muscle to bone
What is the epimysium?
Epimysium is a connective tissue that covers the entire skeletal muscle.
What is fascia?
It is a fibrous tissue that is web like
What is a muscle fibre cell?
A muscle fibre cell is composed of many fibrils which give the cell its striated appearence. Myofibrils are bundles of myofilament (actin & myosin)
In what order would you perform an extra-oral soft tissues exam.
- Check the whole face 2. Check facial symmetry 3. Cheeks 4. Nose, philtrum, nasolabial groove 5. Lips 6. Mandible 7. TMJ 8. Lymph nodes
In what order would you perform an inter oral exam of the vestibule
- Upper and lower fornix 2. Gingiva 3. Overall colour and texture 4. Mucogingival junction 5. Alveolar mucosa 6. Frenae 7. Maxillary tuberosity. 8. Retromolar triangle
`What comprises the central nervous system?
Nerves, ganglia, nerve endings
How many peripheral nerves are thre?
31 pairs
How many cranial nerves are there?
12
What elements are there in the peripheral nerve structure?
Epinerium, perinerium and endonerium
What cell type malinates the central nervous system neuron?
Oligodendrocyte
What cell type malinates the peripheral nervous system neuron?
Schwann cell
What are the most relevant nerves for dental practice?
CN V & CN VII
Using the ionic basis of resting membrane potential explain which ions are move n which dirrection to maintain V of -60mV
Potassium can go either in or out, sodium usually goes in in small amounts, calcium goes in in very small amounts, chloride goes in in very small amounts. Special ATP pump is available to pump 3 sodiums out and bring 2 potassiums in.
WHat hapens when membrane potential goes above 0 mV?
Cell is depolorised
What happens if it goes from + to - ?
It is repolorised
What happens if it goes below the rest membrane potential?
It is hyperpolarised
What is the formula for electrical work?
Work = (the amount of ions moved)(charge of ions moved)(constant)*(voltage gradient)
The formula for chemical work is?
Work = (the amount of ions moved)(constant)(constant)*ln(concentration gradient)
What is the resting potential for potassium?
-93 mV
What is the resting potential for sodium?
+60 mV
What is the resting potential for chlorine?
-62 mV
How does depolarisation happen?
Openning of sodium channels
How does repolarisation happen?
Increased permiability to potassium
What structure conducts the action potential in a neuron?
Axon
What do myelinated axons have?
Nodes
What is a refractory period?
It is a period where a large number of sodium channels are unable to open thus, even witha big stimulus there will be no response
What is presynapsis?
It is electrical to chemical signal
What is post synapses?
It is chemical to electrical signal
What are the three types of crine signaling?
Autocrine, paracrine, endocrine
What are the three main types of hormones?
Peptides and proteins, steroids and amines
What are the two types of heart circulation?
Systemic and Pulmonary
What vessels does blue (depleted of oxygen blood) use?
Systemic veins, pulmonary arteries.
What vessels does red (oxygenated blood) use?
Systemic arteries, pulmonary veins
What are the four great vessels of the heart?
Aorta, superior & inferior vena cavae, pulmonary artery, pulmonary veins
What is the pericardium?
double-walled sac containing the heart and the roots of the great vessels.
What are the muscle of the heart called?
Myocardium (forms the mid layer)
What is the endocardium?
Inner heart lining
Rank blood vessels from largest to largest.
Arteries, arterioles, capillaries, venules, veins
What are the three layers of the vascular wall?
- Tunica intima 2. Tunica media 3. Tunica adventitia
What is an endothelial cell?
Endothelial cells form the barrier between vessels and tissue and control the flow of substances and fluid into and out of a tissue.
What factors are produced by the EC?
Vasodilators, antithrombotic, growth inhibitors, vasoconstrictors, prothrombotic, growth promotrs
What elements are in blood?
Cells, plsma, cell fragments (platelets)
What proteins are present in plasma?
Albumin, globulins, fibrinogen
What are the five major types of white blood cells?
Monocytes, lymphocyes, neutrophil, basophil, eosinophil
What area of the mouth do we cover in periodontology?
Gingiva, periodontal attachment apparatus, cementum, periodontal ligament, alveolar bone
What is the function of gingiva?
Gingiva protects the udnerlying tooth structures
What it the area of the gingiva closest to the tooth?
Gingival margin
What it the line called that attaches alveolar mucosa to the gingiva?
Mucogingival junction
What is the gingiva that is situated between the teeth called?
Interdental papilla
What is the name of the fibres present in the periodontal ligament?
Sharpey’s fibres
What is the first type of cementum?
Acellular, afibrillar cementum (mineralized ground substance produced by cementoblasts)
What is the second type of cementum?
Acellular, extrinsic-fiber cementum (densely packed fibres, produced by cementoblasts and fibroblasts)
What is the third type of cementum?
Cellular intrinsic-fiber cementum (circular fibres, produced by cementoblasts)
What is the forth type of cementum?
Cellular mixed-fiber cementum (extrinsic and intrinsic fibers, produced by cementoblasts and fibroblasts)
What are the three part of the alveolar bone?
- Alveolar bone proper 2. Trabecular bone 3. Compact bone
What is the main difference in term of calcium use between cardiac/skeletal muscle to smooth muscle?
Cardiac/skeletal muscle use Ca2+ troponin for regulation of contraction while smooth muscle use Ca2+ calmodulin
What are the three way we can stimulate hormone release?
Hormonal, neural and humoral
Why is calcium important?
Bone strength, control calcium channels, cardia and skeletal muscle, neurotransmitters etc
What does PTH do?
Increase the reabsorption of calcium in the nephron by use of vitamin D
What is a periodontal pocket?
A periodontal pocket is a pathologic increase in the depth of the gingival crevice or sulcus surrounding a tooth at the gingival margin
What is the normal depth for PPD?
3mm
What are the three major sweat glands?
- Parotid gland (serous acini) 2. Submandibular glands (serous and mucous acini) 3. Sublingual gland (mucous)
What are the two types of saliva?
- Primary 2. Secondary
