Final Exam Flashcards
Outer to inner layers
- Thick Peptidoglycan Cell Wall (This gets stained Purple by Gram Stains)
- Periplasmic Space
- Plasma Membrane
Gram Positive
Outer to inner layers
- Outer Membrane (Lipopolysaccharide and Protein)
- Periplasmic Space
- Thin Peptidoglycan Cell Wall
- Plasma Membrane
Gram Negative
This causes caries by dissolving the enamel and dentin
Lactate
People who keep their teeth clean and have no periodontal diseases have more XXXX facultative anaerobes in their mouth.
Gram Positive
Thick wall of Gram +ve bacteria allows them to tolerate the low pH caused by lactate.
These agents are used to stop hemorrhage from inflamed pulp and injured gingiva
Hemostatic agents
These hemostatic agents shrink or constrict tissues
astringents
What are the best Dental Astringents:
zinc, Iron, and Aluminum salts
- This astringent is Common in gingival retraction because of its astringent abilities
- Can precipitate protein, constrict blood vessels, and extract fluid from tissues. Highly soluble in water
Aluminium Chloride
This astringent on an open wound results in agglutination of surface proteins leading to quick and efficient hemostasis
Ferric Subsulfate solution (Monsel’s solution)
Which coagulation pathway is this?
- triggered when blood comes into physical contact with abnormal vessel wall (e.g from infection, bacteria in blood vessel, anything unusual)
- Factor XII, XI, & IX becomes active which triggers factor X activation leading to the final common pathway
Intrinsic Pathway
Which coagulation pathway is this?
- initiated by factors released from injured tissues (tissue factors) into the blood
- Factor VII becomes activated which triggers factor X to be activated as well leading to the final common pathway
Extrinsic Pathway
Final coagulation common pathway in chronological order
- Prothrombin (II) → Thrombin (IIa) (Pro- Before)
- Fibrinogen (I) → Fibrin (Ia) (gen- Genesis> It makes Fibrin)
- XIIIa aids form to cross-linked fibrin clot
This protein is found in: Hair, wool, skin, horns and fingernails; composed of α-helical polypeptides
Keratin
What type of keratin is this? these type of areas: outer surface of hard palate and gingival mucosa
Parakeratinized areas
What type of keratin is this? cheeks, lips, ventral surface of tongue, soft palate; allows permeability of small fluids and molecules
Nonkeratinized regions:
What type of collagen is this?
- formed in the intracellular matrix
- selected hydrolysine residues are glycosylated with glucose and galactose
Procollagen
What type of collagen is this?
- It is formed in the extracellular matrix
- secreted by a golgi vacuole into the extracellular matrix
- the n-terminal and c-terminal are cleaved by peptidases
tropocollagen
This is not included in the synthesis of enamel
- Collagen
- ameloblasts
- enamelin
- amelogenin
Collagen
What is the composition of ? 33% Glycine; ~30% Proline and Hydroxyproline
Collagen
Which collagen oral disorder is this? fragile bones
33% Glycine; ~30% Proline and Hydroxyproline
Which collagen oral disorder is this? opalescent or completely missing teeth
Detinogenesis imperfecta:
- Ascorbate cannot be made by humans as we lack L-gulonolactone oxidase
- Protects macromolecules from oxidative damage by neutralizing ROS
- Antioxidant property is more important extracellularly
- Deficiency leads to periodontal disease (scurvy)
- Loss of gingival and periodontal membrane fibers → loosening of teeth
- Periodontal membrane fibers are removed but not replaced → slow turnover of collagen in bone
Ascorbate (vitamin C) is important in the hydroxylation (proline and lysine) of collagen
- What is the main mineral in teeth?
- formed during mineralization - calcium, phosphate, and hydroxide ions combine to form it
Hydroxyapatite: Ca10(PO4)6(OH)2; a dimer and highly insoluble
What are the hard tissues in the tooth?
Enamel
Dentin
What tissue formation is described below?
- Formed in the extracellular matrix with amelogenins and enamelins (both are proteins) as building blocks
- Ameloblasts secretes amelogenins and enamelins; present only during development
Enamel formation
What tissue formation is described below?
Formed around the pulp on an extracellular matrix of collagen and non-collagenous proteins secreted by odontoblasts
Dentin formation
This process includes the following:
- Scaffolding proteins (“rebars of teeth production”): collagen, amelogenins
- High concentration of ions: calcium, phosphate
- Process called nucleation
- calcium, phosphate, and hydroxide ions combine to form solid hydroxyapatite
Mineralization
- What happens to the enamel at pH 5.5
- Protons diffuse into hydroxyapatite crystal to react with OH group to change the crystal into an amorphous calcium monohydrogen phosphate solid that slowly dissolves.
- Ca10 (PO4)6 (OH)2 -> CaHPO4
- Acids lower pH and strip Calcium and Phosphate off from tooth
Demineralization
These cells mineralize dentin in the presence of many factors on a scaffolding protein called collagen
Odontoblasts
These cells mineralize enamel in the presence of protein factors including a scaffolding protein class called amelogenins
Ameloblasts
This part of the tooth mineralizes towards the pulp
dentin
This part of the tooth mineralizes towards the crown and loses ameloblasts
enamel
In the oral cavity, what do bacteria metabolize aerobically?
CO2 and H2O
In the oral cavity, what do bacteria metabolize anaerobically?
lactic acid - we do not want this
- Made by ameloblasts
- Only calcified tissue that does NOT contain collagen
- 97% by weight mineral (hardest substance in the body)
- Less than 1% by weight protein
Enamel
- Made by odontoblasts
- Calcified over type 1 collagen fibers like bone
- 70% mineral
- 30% protein
Dentin
- Primary function is to form dentin (by the odontoblasts)
Pulp
Which genetic structure is this?
- Polymer of deoxyribonucleoside monophosphates linked by 3’⇢5’ phosphodiester bonds
- consists of two strands, arranged in a double helix. These strands are made up of subunits called nucleotides. Each nucleotide contains a phosphate, a 5-carbon sugar molecule and a nitrogenous base.
DNA
Which genetic structure is this? Single stranded helix
- Ribonucleotides joined by phosphodiester bonds
- ribose sugar
- 3 classes
- mRNA
- rRNA
- tRNA
RNA
- Begins at a site called the origin of replication by DnaA protein (Mainly A-T base pairs)
- DNA Helicase unwinds the double helix while ssDNA-binding proteins keep the strands apart and protect DNA from nucleases
- Primase adds an RNA primer with a free OH on the 3’ end
- DNA Pol III synthesizes in 5’ -> 3’ direction with leading and lagging strands until it reaches proximity to an RNA primer
- Topoisomerase I (Cuts 1 strand) and Topoisomerase II (Cuts both strands) removes supercoils. Example.
- RNA primer is excised and gap filled by DNA Pol I
- DNA Ligase links the final phosphodiester linkage of DNA chain synthesized by DNA pol III with the chain made by DNA Pol I
DNA replication in prokaryotes
Which enzyme unwinds the double helix in DNA replication of prokaryotes?
DNA Helicase
what keeps the SNA strands apart and protects DNA from nucleases?
Single Stranded DNA binding proteins
This enzyme adds an RNA primer with a free OH on the 3’ end
Primase
This DNA polymerase synthesizes in 5’ -> 3’ direction with leading and lagging strands until it reaches proximity to an RNA primer
DNA Pol III
This enzyme cuts 1 strand of DNA during DNA Replication in prokaryotes
Topoisomerase I
This enzyme cuts both DNA strands and removes supercoils during DNA replication in prokaryotes
Topoisomerase II (Cuts both strands) removes supercoils
During DNA replication in prokaryotes, XXXX is excised and the gap is filled with XXXX
RNA Primer, DNA Pol I
This enzyme links the final phosphodiester linkage of DNA chain synthesized by DNA pol III with the chain made by DNA Pol I
DNA ligase
- RNA Polymerase attaches to TATAA Box (TATAAT sequence) (Doesn’t require primer)
- Proceeds along DNA anti-sense strand with RNA growing 5’ -> 3’ direction
- Rho-independent termination - Generates sequence of self-complementary bases that causes it to fold on itself forming a hairpin loop. This facilitates separation of RNA from DNA
- Rho-dependent termination - Rho uses its ATP-dependent helicase activity to separate RNA from DNA
- RNA is used as unaltered primary transcript as soon as it is made. (Prokaryotes will often begin translation as transcription is taking place as they don’t have a nucleus to separate them)
This is the Transcription in Prokaryotes process
This type of termination in the transcription process in prokaryotes generates sequence of self-complementary bases that causes it to fold on itself forming a hairpin loop. This facilitates separation of RNA from DNA
Rho-independent termination
During this type of termination in the transcription process of prokaryotes, Rho uses its ATP-dependent helicase activity to separate RNA from DNA
- Rho-dependent termination
T/F
RNA is used as unaltered primary transcript as soon as it is made. (Prokaryotes will often begin translation as transcription is taking place as they don’t have a nucleus to separate them)
True
T/F
RNA Polymerase attaches to TATAA Box (TATAAT sequence) (Doesn’t require primer)
True
T/F
During transcription in prokaryotes, the process proceeds along DNA anti-sense strand with RNA growing 5’ -> 3’ direction
True
RNA primers during DNA replication in eukaryotes are removed by?
- DNA Pol I
- RNase
- DNA Pol III
- DNA Ligase
RNase
T/F
DNA replication in prokaryotes has multiple origins of replication because it has larger DNA
F; DNA replication in prokaryotes has one origin of replication because it has small DNA, Eukaryotes have multiple origins of replication because they have large DNA
What happens in transcription of eukaryotes?
- Similar to prokaryotes except it involves separate polymerases along with transcription factors
- Undergoes modification of RNA through capping at 5’ end, addition of Poly(A) tail at 3’ end, and removal of introns
- RNA Polymerase attaches to TATAA Box (TATAAT sequence) (Doesn’t require primer)
- 1&3
- All the above
- Similar to prokaryotes except it involves separate polymerases along with transcription factors
- Undergoes modification of RNA through capping at 5’ end, addition of Poly(A) tail at 3’ end, and removal of introns
- DNA polymerase that Elongates okazaki fragments of lagging strand
DNA Pol 𝛿 (delta)
DNA polymerase that Elongates the leading strand
DNA Pol ɛ (epsilon)
- DNA polymerase that Synthesizes rRNA (rRNA is 80% of RNA in cell)
RNA Pol I
DNA polymerase that Synthesized mRNA
RNA Pol II -
DNA polymerase that - synthesized tRNA and 5S rRNA
RNA Pol III
Which type of mutation is this? One amino acid is swapped for another. (Effects on RNA)
Purine with Purine or Pyrimidine with Pyrimidine. (A>G)
Transition
Which type of mutation is this? One amino acid is swapped for another. (Effects on RNA)
Purine with Pyrimidine or the other way. (A>T/U)
Transversion
Substitution can lead to 3 different types of mutations. (Effects on Protein)
- No change to Protein because some Codons are redundant.
Silent Mutation
Substitution can lead to 3 different types of mutations. (Effects on Protein)
- Different Amino Acid. (This protein might still work if the change was to a similar size and type of AA)
Missense Mutation
Substitution can lead to 3 different types of mutations. (Effects on Protein)
- Forms a Stop codon. (This protein will most likely not work at all)
Nonsense Mutation
DNA mutation where an insertion or deletion happens leading to huge changes in the reading frame. This protein is also going to be garbage as every codon after the mutation will be ruined)
Frameshift mutation
DNA Damage can be caused by the following
- Hydrolysis
- Oxidation
- Methylation
- UV Light:
- Forms Pyrimidine Dimers (THYMINE)
- Ionizing Radiation:
- Damages DNA Directly
- Forms Strand Breaks in the Double Helix.
DNA damage that Forms Pyrimidine Dimers (THYMINE)
UV Light
DNA damage that causes
- Damages DNA Directly
- Forms Strand Breaks in the Double Helix.
Ionizing Radiation
Which type of DNA repair disease is this?
- Pyrimidine dimers formed in skin cells exposed to UV light
- Defects in excision repair due to mutant UV specific endonuclease
Xeroderma pigmentosum
Which type of DNA repair disease is this?
- Defects in excision repairs
- Neurodegenerative disease
- Poor coordination
Ataxia Telangiectasia
Which type of biotechnology is this? separate macromolecules based on charges and size (Gel separates the size and Electricity separates by charge)
Gel Electrophoresis
Which type of biotechnology is this? detect specific proteins.
Western Blotting
Which type of biotechnology is this? detects specific DNA sequences
Southern Blotting
Which type of biotechnology is this? detects specific RNA sequences
Northern Blotting
Which type of biotechnology is this? amplify small samples of DNA
polymerase chain reaction (PCR)
Which type of biotechnology is this? separate components of mixture via columns
High Performance Liquid Chromatography (HPCL)
Which type of biotechnology is this? determine molecular 3D structures
X-ray Crystallography and Nuclear Magnetic Resonance
Which type of biotechnology is this?
- determine amino acid sequence of peptide
Edman Degradation
Which type of biotechnology is this? determine amino acid sequence of peptide
Mass Spectrometry (more modern)
SNOW DROP mnemonic
Southern blot
Northern blot
O
Western blot
DNA
RNA
O
Protein
Start Codon is AUG and codes for
Methionine
- Stop Codons are
- Stop Codons are UAG, UAA, UGA.
- Generic code is XXX or XXX. eg: Valine is coded by GUU, GUC, GUA and GUG.
- This means the third AA is allowed to be anything and it will still code for the same thing (Called a silent mutation!)
protein that provides structural support for a chromosome
histone
Each chromosome contains a long molecule of DNA, which must fit into the cell nucleus. To do that, the DNA wraps around complexes of histone proteins, giving the chromosome a more compact shape
- Eukaryotic DNA is packaged with histones into nucleosomes which also pack into chromosomes.
- DNA> Nucleosome beads (Histone core + DNA) > Chromosomes
Histones