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.