| 4906061037 | amino acid | have 4 groups attached to a central carbon
- amino group
- carboxylic acid group
- a hydrogen atom
- R group | | 0 |
| 4906061038 | Stereochemistry for amino acids | at the alpha carbon the stereochemistry is always L in eukaryotes. D-amino acids can exist in prokaryotes. All amino acids except cysteine have S configuration. Glycine is the only amino acid that is not chiral. | | 1 |
| 4906061039 | nonpolar, nonaromatic side chain | glycine, alanine, valine, leucine, isoleucine, methionine, proline | | 2 |
| 4906061040 | aromatic side chain | tryptophan, phenylalanine, tyrosine | | 3 |
| 4906061041 | polar side chain | serine, threonine, asparagine, glutamine, cystine | | 4 |
| 4906061042 | negatively charged side chain (acidic) | asparatate, glutamate | | 5 |
| 4906061043 | positively charged side chain (basic) | lysine, arginine, histidine | | 6 |
| 4906061044 | amphoteric | can accept or donate protons | | 7 |
| 4906061045 | pKa | is the pH at which half of the species is deprotonated
[HA] = [A-] | | 8 |
| 4906061046 | Amino acids at different pH values | low pH = fully protonated
pH near the pI = neutral zwitterion
high pH = fully deprotonated | | 9 |
| 4906061047 | isoelectric point | can be calculated by averaging the two pKa values of the amino acids without a charged side chain | | 10 |
| 4906061048 | titration of an amino acid | the curve will be nearly flat at the pKa values of the amino acid and nearly vertical at the pI of the amino acid | | 11 |
| 4906061049 | pI of amino acids | Acidic amino acids have a pI well below 6
Basic amino acids have a pI well above 6
Amino acids without charged side chains have a pI around 6 | | 12 |
| 4906061050 | formation of a peptide bond | occurs via a condensation or dehydration reaction. The nucleophilic amino group of one amino acid attacks the electrophilic carbonyl group of another amino acid.
*Note that amino bonds are rigid because of resonance. | | 13 |
| 4906061051 | breaking of a peptide bond | occurs via hydrolysis.
In the body: trypsin -> cleaves at the carboxyl end of arginine and lysine. Chymotrypsin -> cleaves at the carboxyl end of phenylalanine, tryptophan, and tyrosine.
Organic chemistry: hydrolyzes the amide bond using acid or base catalysis | | 14 |
| 4906061052 | primary structure | is the linear sequence of amino acids in a peptide and is stabilized by peptide bonds |  | 15 |
| 4906061053 | secondary structure | is the local structure of neighboring amino acids and is stabilized by hydrogen bonding between amino acid groups and non adjacent carboxyl groups |  | 16 |
| 4906061054 | alpha helix | are clockwise coils around a central axis | | 17 |
| 4906061055 | beta pleated sheets | are rippled strands that can be parallel or antiparallel | | 18 |
| 4906061056 | proline | can interrupt secondary structure because its rigid cyclic structures | | 19 |
| 4906061057 | tertiary structure | is the three-dimensional shape of a single polypeptide chain, and is stabilized by hydrophobic interactions, acid-base interactions, hydrogen bonding, and disulfide bonds | | 20 |
| 4906061058 | hydrophobic interactions | push hydrophobic R groups to the interior side of a protein which increased entropy of the surrounding water molecules and creates negative Gibbs free energy | | 21 |
| 4906061059 | disulfide bonds | occur when two cysteine molecules are oxidized and create a covalent bond to form cystine | | 22 |
| 4906061060 | quaternary structure | is the interaction between peptides in proteins that contain multiple subunits | | 23 |
| 4906061061 | denaturation of proteins | can occur through heat and increasing solute concentration which lead to loss of three-dimensional protein structure | | 24 |
| 4906061062 | isoelectric point of a neutral amino acid | pI = pKa NH+ group + pKa COOH group / 2 | | 25 |
| 4906061063 | Isoelectric point of an acidic amino acid | pI = pKa R group + pKa COOH group / 2 | | 26 |
| 4906061064 | isoelectric point of basic amino acid | pI = pKa NH+ group + pKa R group / 2 | | 27 |
| 4906061065 | enzymes | are biological catalysts that are unchanged by the reactions they catalyze and are reusable. | | 28 |
| 4906061066 | Key features of enzymes | lower activation energy
increase the rate of reaction
do not alter the equilibrium constant
are not changed or consumed in the reaction
are pH and temperature- sensitive, with optimal activity at specific pH ranges and temperatures
do not affect the overall delta G of the reaction
are specific for a particular reaction or class of reaction | | 29 |
| 4906061067 | oxidoreductase | catalyze oxidation-reduction reactions that involve the transfer of electrons | | 30 |
| 4906061068 | transferases | move a functional group from one molecule to another molecule | | 31 |
| 4906061069 | hydrolases | catalyze clevage with the addition of water | | 32 |
| 4906061070 | lyases | catalyze cleavage without the addition of water and without the transfer of electrons. The reverse reaction (synthesis) is often more important biologically. | | 33 |
| 4906061071 | isomerases | catalyze the interconversion of isomers, including both constitutional isomers and stereoisomers | | 34 |
| 4906061072 | ligases | are responsible for joining two large biomolecules , often of the same type | | 35 |
| 4906061073 | Mnemonic for Major Enzyme Classifications | LI'L HOT | | 36 |
| 4906061074 | exergonic reactions | release energy; delta G is negative | | 37 |
| 4906061075 | mechanism of enzymes | They do not alter the free energy or enthalpy change that accompanies the reaction nor the final equilibrium position. It does however change the rate (kinetics) at which equilibrium is reached. They act by stabilizing the transition state, providing a favorable miroenvironment, or bonding with the substrate molecules. | | 38 |
| 4906061076 | lock and key theory | hypothesizes that the enzyme and substrate are exactly complementary | | 39 |
| 4906061077 | induced fit model | hypothesizes that the enzyme and substrate under go a conformational change to interact fully | | 40 |
| 4906061078 | substrate kinetics | as a substrate concentration increases the reaction rate does as well until a maximum value is reached | | 41 |
| 4906061079 | Michaelis- Menten rate | |  | 42 |
| 4906061080 | Michaelis-Menten equation | |  | 43 |
| 4906061081 | Michaelis-Menten plot | |  | 44 |
| 4906061082 | Lineweaver-Burk plot | |  | 45 |
| 4906061083 | cooperative enzymes | display a sigmoidal curve because of the changes in activity with substrate binding | | 46 |
| 4906061084 | feedback inhibition | is a regulatory mechanism whereby the catalytic activity of an enzyme is inhibited by the presence of high levels of a product later in the same pathway | | 47 |
| 4906061085 | reversible inhibition | is characterized by the ability to replace the inhibitor with a compound of greater affinity or to remove it using mild laboratory treatment | | 48 |
| 4906061086 | competitive inhibition | results when the inhibitor is similar to the substrate and bind at the active site. This can be over come by adding more substrate. Vmax is unchanged and Km increases |  | 49 |
| 4906061087 | noncompetitive inhibition | results when the inhibitor binds to an allosteric site instead of the active side which induces a change in enzyme conformation. Vmax is decreased and Km is unchanged. |  | 50 |
| 4906061088 | mixed inhibition | results when the inhibitor binds with unequal affinity to the enzyme and the enzyme-substrate complex. Vmax is decreases and Km is increased or decreased depending on if the inhibitor has a higher affinity for the enzyme or enzyme-substrate complex. |  | 51 |
| 4906061089 | uncompetitive inhibition | results when the inhibitory binds only with the enzyme substrate complex. Km and Vmax both decrease. |  | 52 |
| 4906061090 | irreversible inhibition | alters the enzyme in such a way that the active site is unavailable for a prolonged duration or permanently. New enzyme molecules must be synthesized for the reaction to occur again | | 53 |
| 4906061091 | allosteric sites | can be occupied by activators which increase either affinity or enzymatic turnover | | 54 |
| 4906061092 | Phosphorylation and glycosylation | can alter the activity or selectivity of enzymes | | 55 |
| 4906061093 | zymogens | are secreted in inactive form and are activated by cleavage | | 56 |
| 4906061094 | structural proteins | compose the cytoskeleton , anchoring proteins, and much of the extracellular matrix | | 57 |
| 4906061095 | Most common structural proteins | collagen, elastin, keratin, actin, and tubulin | | 58 |
| 4906061096 | collagen | thee alpha helices woven together and make up most of the extracellular matrix of connective tissue. It provides strength and flexibility | | 59 |
| 4906061097 | elastin | found in the extracellular matrix of connective tissue and primarily functions to stretch and recoil. | | 60 |
| 4906061098 | keratin | are intermediate filament protein found in epithelial cells. They provide mechanical integrity of the cell and function as regulatory proteins.
Ex: hair and nails | | 61 |
| 4906061099 | actin | makes up microfilaments and the thin filaments in myofibrils. It is the most abundant protein in eukaryotic cells. It contains a positive and negative end which allows motor proteins to travel along it. | | 62 |
| 4906061100 | tubulin | makes up microtubules. It provides structure, chromosome separation in mitosis, and intracellular transport with kinesin and dynein. | | 63 |
| 4906061101 | motor proteins | have one or more heads capable of force generation through a conformational change.
Ex: myosin, kinesin, and dynein | | 64 |
| 4906061102 | myosin | is the primary motor protein that interacts with actin. It is also found in the thick filament in a myofibril. Each subunit has a head and a neck. Movement at the neck is responsible for the power stroke of sarcomere contraction. | | 65 |
| 4906061103 | kinesin and dyneins | are motor proteins associated with microtubules. They have two head, in which one remains attached to tubulin at all times. Kinesin brings vesicles to the positive end while dyneins go toward the negative end. |  | 66 |
| 4906061104 | Application of motor proteins | muscle contraction, vesicle movement within cells, and cell motility. | | 67 |
| 4906061105 | binding protiens | bind specific substrate, either to sequester in the body or hold its concentration at a steady state | | 68 |
| 4906061106 | Cell adhesion molecules (CAMs) | are integral membrane proteins that allow cells to bind to other cells or surfaces. | | 69 |
| 4906061107 | cadherins | are calcium dependent glycoproteins that hold similar cells together | | 70 |
| 4906061108 | integrins | have two membrane-spanning chains and permit cells to adhere to proteins in the extracellular matrix. Some also have signaling capabilities | | 71 |
| 4906061109 | selectins | allow cells to adhere to carbohydrates on the surface of other cells and are most commonly used in the immune system | | 72 |
| 4906061110 | antibodies | also called imunoglobulins are used by the immune system to target a specific antigen, which may be a protein on the surface of a pathogen or a toxin | | 73 |
| 4906061111 | antibody structure | contains a constant region and a variable region which is responsible for antigen binding. It has two identical heavy chains and two identical light chins that are held together by disulfide linkages and noncovalent interactions. | | 74 |
| 4906061112 | opsonization | marking the pathogen for destruction by other white blood cells immediately | | 75 |
| 4906061113 | agglutination | clumping together the antigen and antibody into a large insoluble protein complex that can be phagocytized and digested by macrophages | | 76 |
| 4906061114 | ion channels | can be use for regulating ion flow into or out of a cell. There are three main types of channels
1) ungated channels are always open
2) voltage-gated channels are open within a range of membrane potentials
3) ligand-gated channels open in the presence of a specific binding substance, usually a hormone or neurotransmitter | | 77 |
| 4906061115 | facilitated difusion | is a type of passive transport that allows the diffusion of molecules down a concentration gradient through a pore in the membrane created by transmembrane proteins | | 78 |
| 4906061116 | enzyme linked receptors | participate in cell signaling through extracellular ligand binding and initiation of second messenger cascades. They have three primary protein domains including the membrane-spanning domain, ligand-binding domain, and a catalytic domain. | | 79 |
| 4906061117 | membrane spanning domain | anchors the receptor in the cell membrane | | 80 |
| 4906061118 | ligand binding domain | is stimulated by the appropriate ligand and induces a conformational change that activates the catalytic domain | | 81 |
| 4906061119 | G protein-coupled receptors | have a membrane-bound protein associated with a trimeric G protein. They also initiate second messenger systems | | 82 |
| 4906061120 | Functions of heterotrimeric G proteins | Gs: stimulates adenylate cyclase increasing levels of cAMP
Gi: inhibits adenylate cyclase decreasing levels of cAMP
Gq : activates phospholipase C which cleaves a phospholipid from the membrane to form PIP2. PIP2 is then cleaved into DAG and IP3; IP3 can open calcium channels in the ER to increase calcium levels in the cell | | 83 |
| 4906061121 | How G protein-coupled receptors work | 1) ligand binding engages the G protein
2) GDP is replaces with GTP; the alpha subunit dissociates from the beta and gamma subunits
3) the activated alpha subunit alters the activity of adenylate cyclase or phospholipase C
4) GTP is dephosphorylated to GDP; the alpha subunit rebinds to the beta and gamma subunits | | 84 |
| 4906061122 | electrophoresis | uses a gel matrix to observe the migration of proteins in response to an electric field | | 85 |
| 4906061123 | native PAGE | maintains the protein's shape, but results are difficult to compare because the mass-to-charge ration differs for each protein. Most useful to compare the molecular size or the charge of proteins known to be similar in size | | 86 |
| 4906061124 | SDS-PAGE | denatures the proteins and masks the native charge so that comparison of size is more accurate, but the functional protein cannot be recaptured from the gel | | 87 |
| 4906061125 | isoelectric focusing | separates proteins by their isoelectric point; the protein migrates toward an electrode until it reaches a region of the gel where pH = pI of the protein | | 88 |
| 4906061126 | chromatography | separates protein mixtures on the basis of affinity for a stationary phase or a mobile phase | | 89 |
| 4906061127 | column chromatography | uses beads of a polar compound, like silica or alumina (stationary phase), with nonpolar solvent (mobile phase) |  | 90 |
| 4906061128 | ion-exchange chromatography | uses a charged column and a variably saline eluent |  | 91 |
| 4906061129 | size-exclusion chromatography | relies on porous beads. Larger molecules elute first because they are not trapped in the small pores |  | 92 |
| 4906061130 | affinity chromatography | uses a bound receptor or ligand and an eluent with free ligand or a receptor for the protein of interest |  | 93 |
| 4906061131 | X-ray crystallography | is used primarily to determine protein structure after a protein is isolated. NMR can also be used but this is less common | | 94 |
| 4906061132 | Edman degradation | is used to determine amino acid sequencing. Amino acid composition can be determined by simple hydrolysis but this will not yield the order | | 95 |
| 4906061133 | UV spectroscopy | can be used to determine protein concentration | | 96 |
| 4906061134 | Bradford protein assay | this is the most common method for testing protein concentration and uses a color change from brown-green to blue. This method is limited by the presence of detergent and excessive buffer. It is also less accurate when more than one protein is present. | | 97 |
| 4906061135 | Migration velocity | V = Ez/ f | | 98 |
| 4906061136 | aldoses | sugars with aldehydes at their most oxidized group | | 99 |
| 4906061137 | ketoses | sugars with ketones at their most oxidized group | | 100 |
| 4906061138 | D sugars | sugars with the highest-numbered chiral carbon with the -OH group on the right | | 101 |
| 4906061139 | L sugars | sugars with the highest-numbered chiral carbon with the -OH on the left | | 102 |
| 4906061140 | Common monosaccarides | |  | 103 |
| 4906061141 | Stereoisomers | Compounds that have the same Chemical formula but differ in spatial arrangement of their component atoms | | 104 |
| 4906061142 | Enantiomers | A stereoisomer that is non-identical, non-superimposable mirror images of each other |  | 105 |
| 4906061143 | diastereomers | are non-superimposable configurations of molecules with similar connectivity. They differ at at least one chiral carbon | | 106 |
| 4906061144 | epimers | are a subtype of diasteromers that differ at exactly one chiral carbon |  | 107 |
| 4906061145 | anomers | are a subtype of epimers that differ at the anomeric carbon | | 108 |
| 4906061146 | anomeric carbon | is the new chiral center formed in ring closure; it was the carbon containing the carbonyl in the straight-chain form. | | 109 |
| 4906061147 | alpha anomers | have the -OH on the anomeric carbon trans to the free -CH2OH group | | 110 |
| 4906061148 | beta anomers | have the -OH on the anomeric carbon cis to the free -CH2OH group | | 111 |
| 4906061149 | Haworth projections | provide a good way to represent three dimensional structure | | 112 |
| 4906061150 | mutarotation | cyclic compounds shift from one anomeric form to another with the straight-chain form as an intermediate | | 113 |
| 4906061151 | monosaccharides | are single carbohydrates units, with glucose as the most commonly observe monomer | | 114 |
| 4906061152 | Tollen's or Benedict's reagents | are used to determine reducing sugars | | 115 |
| 4906061153 | Tautomerization | Refers to the rearrangement of bonds in a compound, usually by moving a hydrogen and forming a double bond | | 116 |
| 4906061154 | deoxy sugars | are sugars with a -H replacing an -OH group | | 117 |
| 4906061155 | Esterification | sugars can react with carboxylic acids and their derivatives to form esters | | 118 |
| 4906061156 | phosphorylation | a phosphate ester is formed by transferring a phosphate group from ATP one a sugar | | 119 |
| 4906061157 | glycoside formation | is the basis for building complex carbohydrates and requires the anomeric carbon to link to another sugar | | 120 |
| 4906061158 | disaccharides | form as result of glycosidic bonding between two monosaccarides subunits. | | 121 |
| 4906061159 | sucrose | glucose- alpha- 1,2-fructose |  | 122 |
| 4906061160 | lactose | galactose- beta- 1,4 - glucose |  | 123 |
| 4906061161 | maltose | glucose- alpha- 1,4- glucose |  | 124 |
| 4906061162 | cellulose | is the main structural component for plan cell walls and is a main source of fiber in the human diet |  | 125 |
| 4906061163 | starches | include amylose and amylopectin and function as a main energy storage form for plants |  | 126 |
| 4906061164 | glycogen | functions as a main energy storage form for animals | | 127 |
| 4906061165 | Phospholipids | are amphipathic and form the bilayer of biological membranes. They contain a hydrophilic head and hydrophobic tails. The saturation of the fatty acid tails determine the fluidity of the membrane | | 128 |
| 4906061166 | glycerophospholipids | are phospholipids that contain a glycerol backbone | | 129 |
| 4906061167 | sphingolipids | are phospholipids that contain a sphingosine or sphingoid backbone | | 130 |
| 4906061168 | types of sphingolipids | |  | 131 |
| 4906061169 | sphingomyelins | are the major class of sphingophospholipids and contain a phosphatidylcholine or phosphatidylethanolamine head group. They are a major component of the myelin sheath. | | 132 |
| 4906061170 | glycosphingolipids | are attached to sugar moieties instead of a phosphate group. | | 133 |
| 4906061171 | gangliosides | contain oligosaccharides with at least one terminal N-acetylneuraminic acid | | 134 |
| 4906061172 | Waxes | contain long-chain fatty acids esterified to long-chain alcohols. They are used as protection against evaporation and parasites in plants and animals. | | 135 |
| 4906061173 | Terpenes | are odiferous steroid precursors made from isoprene, a five-carbon molecule (C5H8). | | 136 |
| 4906061174 | Terpenoids | are derived from terpenes via oxygenation or backbone rearrangement. | | 137 |
| 4906061175 | steroids | contain three cyclohexane rings and one cyclopentane ring. Their oxidation state and functional groups may vary. |  | 138 |
| 4906061176 | steroid hormones | have high-affinity receptors, work at low concentrations, and affect gene expression and metabolism. | | 139 |
| 4906061177 | cholesterol | is a steroid important to membrane fluidity and stability; it serves as a precursor to a host of other molecules | | 140 |
| 4906061178 | prostaglandins | are autocrine and paracrine hormones that regulate cAMP levels. they have powerful effects on muscle contraction, body temperature, they sleep-wake cycle, and pain. They are unsaturated carboxylic acids derived from arachidonic acid and contain one 5 carbon ring. | | 141 |
| 4906061179 | vitamin A | also called carotene is metabolized to retinal for vision and retinoic acid for gene expression in epithelial development. | | 142 |
| 4906061180 | vitamin D | also called cholecalciferol is metabolized to calcitriol in the kidney's and regulates calcium and phosphorus homeostasis in the intestine (increasing calcium and phosphate absorption), promoting bone formation . A deficiency of vitamin D causes rickets. | | 143 |
| 4906061181 | vitamin E | also called tocopherols and act as biological antioxidants. Their aromatic rings destroy free radicals, preventing oxidative damage. | | 144 |
| 4906061182 | vitamine K | (phylloquinone and menaquiones) is important for formation of prothrombin, a clotting factor. It performs post-translational modifications on a number of proteins, creating calcium-binding sites. | | 145 |
| 4906061183 | triacylglycerols | are the preferred method of storing energy for long-term use. They contain one glycerol attached to three fatty acids by ester bonds and are very hydrophobic. The carbon atoms in lipids are more reduced than carbohydrates, giving twice as much energy per gram during oxidation. |  | 146 |
| 4906061184 | adipocytes | are animal cells specifically used for the storage of large triacylglycerol deposts | | 147 |
| 4906061185 | saponification | is the ester hydrolysis of triacyglycerols using a strong base, like sodium or potassium hydroxide |  | 148 |
| 4906061186 | micelle | is a soap that act as surfactants that can dissolve a lipid-soluble molecule in its fatty acid core and washes away with water because of its shell of carboxylate head groups | | 149 |
| 4906061187 | DNA | is a macromolecule that stores genetic information in all living organisms | | 150 |
| 4906061188 | Nucleosides | contain 5 carbon sugar bound to a nitrogenous base. Nucleotides are nucleosides with one to three phosphate groups added |  | 151 |
| 4906061189 | Nucleotides | adenosine (A), cytosine (C), guanine (G), thiamine (T), and uracil (U) | | 152 |
| 4906061190 | Watson-Crick model | backbone is comprised of alternating sugar phosphate groups and is always read 5' to 3'
there are two strands with antiparallel polarity wound into a double helix
purines (A and G) pain with pyrimidines (C, U, and T).
A-T has two hydrogen bonds while G-C has three hydrogen bonds. In RNA A-U via two hydrogen bonds |  | 153 |
| 4906061191 | Chargaff's rule | state that purines and pyrimidines are equal in number in a DNA molecule and that because of base-pairing the amount of adenine equals the amount of thymine and so on | | 154 |
| 4906061192 | Z-DNA | contains a zig-zag shape and is usually observed with high GC content or high salt concentrations. |  | 155 |
| 4906061193 | B-DNA | is most common and forms a right handed helix | | 156 |
| 4906061194 | Denaturation of DNA | is caused by heat, alkaline pH, and chemicals like formaldehyde and urea. Removal of these conditions may cause reannealing of the DNA | | 157 |
| 4906061195 | 46 | the number of chromosomes in human cells | | 158 |
| 4906061196 | Organization of Eukaryotic Chromosome | DNA is wound around histone proteins to form nucleosomes. Together the DNA and histones make up chromatin which can be divided into heterochromatin (dense, silent DNA that is dark under light spectroscopy) and euchromatin (less dense, active DNA that is light under light spectroscopy). Telomeres are at the end of chromosomes and have a high G-C content to prevent unraveling. Centromeres are located in the middle of the chromosome and hold sister chromatids together until they are separated during anaphase in mitosis. |  | 159 |
| 4906061197 | replisome | is a set of specialized proteins that assist the DNA polymerase | | 160 |
| 4906061198 | Helicases | help to unwind DNA at the origin of replication to produce two replication forks |  | 161 |
| 4906061199 | single stranded DNA binding proteins | protect unwound strands of DNA from reannealing | | 162 |
| 4906061200 | supercoiling | causes torsion strain on the DNA molecule which can be released by DNA topisomerase II (DNA gyrase) which creates nicks in the DNA | | 163 |
| 4906061201 | Semiconservative replication | one old parent strand and one new daughter strand is incorporated into each of the two new DNA molecules | | 164 |
| 4906061202 | Primase | inserts a small RNA primer to begin replication. Without and adjacent nucleotide DNA cannot be synthesized | | 165 |
| 4906061203 | DNA polymerase III / DNA polymerase alpha and delta | for Prokaryotes and Eukaryotes respectively, aids in synthesizing a new strand of DNA. They read the template DNA 3' to 5' and synthesize the new strand 5' to 3' | | 166 |
| 4906061204 | leading strand | requires only one primer and is synthesized continuously in its entirety | | 167 |
| 4906061205 | lagging strand | requires many primers and is synthesized in discrete sections called Okazaki fragments | | 168 |
| 4906061206 | DNA polymerase I / RNase H | for prokaryotes and Eukaryotes respectively, aids in the removal of the RNA primers | | 169 |
| 4906061207 | DNA ligase | fuses DNA strands together to create one complete molecules | | 170 |
| 4906061208 | DNA replication prokaryote vs eukaryote | |  | 171 |
| 4906061209 | oncogenes | develop from mutations of proto-oncogenes, and promote cell cycling. They may lead to cancer. | | 172 |
| 4906061210 | cancer | unchecked cell proliferation with the ability to spread by local invasion or metastasize | | 173 |
| 4906061211 | Tumor repression genes | code for proteins that reduce cell cycling or promote DNA repair; mutations of tumor suppressor genes can also lead to cancer | | 174 |
| 4906061212 | Proofreading | during replication DNA polymerase proofreads its work and excised incorrectly matched bases, the daughter strand is identified by its lack of methylation and corrected accordingly | | 175 |
| 4906061213 | mismach repair | occurs during the G2 phase of cell cycle using the genes MSH2 and MLH1 | | 176 |
| 4906061214 | nucleotide excision repair | fixes helix-deforming lesions of DNA (such as thymine dimers) via a cut-and-patch process that requires and excision endonuclease |  | 177 |
| 4906061215 | base excision repair | fixes nondeforming lesion of the DNA helix (such a cytosine deamination) by removing the base, leaving an apurinic/apyrimidinic (AP) site. An AP endonuclease then removes the damaged sequence, which can be filled in wit the correct bases | | 178 |
| 4906061216 | Recombinant DNA | is DNA composed of nucleotides from two different sources |  | 179 |
| 4906061217 | DNA cloning | introduces a fragment of DNA into a vector plasmid. A restriction enzyme cuts both the plasmid and the fragment which are left with sticky ends. Once the fragment binds to the plasmid it can be introduced into a bacterial cell and permitted to replicate, generating many copies of the fragment of interest. | | 180 |
| 4906061218 | DNA librairies | are large collections of known DNA sequences | | 181 |
| 4906061219 | genomic libraries | contain large fragments of DNA, including both coding and noncoding regions of the genome. They cannot be used to make recombinant proteins or for gene therapy | | 182 |
| 4906061220 | cDNA libraries | contain smaller fragments of DNA and only include the exons of genes expresses by the sample tissue. They can be used to make recombinant proteins or for gene therapy | | 183 |
| 4906061221 | Genomic vs cDNA libraries | |  | 184 |
| 4906061222 | hybridization | is the joining of complementary base pair sequencing. | | 185 |
| 4906061223 | PCR | is an automated process by which millions of copies of a DNA sequence can be created from a very small sample by hybridization | | 186 |
| 4906061224 | agarose gel electrophoresis | method of separating DNA molecules by size | | 187 |
| 4906061225 | southern blotting | can be used to detect the presence and quantity of various DNA strands in a sample. After electrophoresis, the sample is transferred to a membrane that can be probed with single-stranded DNA molecules to look for a sequence of interest | | 188 |
| 4906061226 | DNA sequencing | uses dideoxyribonucleotides with terminate the DNA chain because they lack a 3' -OH group. The resulting fragments can be separated by gel electrophoresis and the sequence can be read directly from the gel | | 189 |
| 4906061227 | gene therapy | is a method of curing genetic deficiencies by introducing a functional gene with a viral vector | | 190 |
| 4906061228 | transgenic mice | are created by integrating a gene of interest into the germ line or embryonic stem cells of a developing mouse. These mice can be mated to select for the transgene | | 191 |
| 4906061229 | chimeras | are organisms that contain cells form two different lineages (such as mice formed by integration of transgenic embryonic stem cells into a normal mouse blastocyst) | | 192 |
| 4906061230 | knockout mice | are created by deleting a gene of interest | | 193 |
| 4906061231 | Central dogma | DNA -> RNA -> proteins | | 194 |
| 4906061232 | Start codon | AUG | | 195 |
| 4906061233 | Stop codon | UGA, UAA, UAG | | 196 |
| 4906061234 | Redundancy/wobble | Occurring in the third-base of a codon allows mutations to occur without effects in the protein | | 197 |
| 4906061235 | Silent mutation | No effect on protein synthesis | | 198 |
| 4906061236 | Nonsense mutation | Also called truncation are mutations that produce a premature stop codon | | 199 |
| 4906061237 | Misssense mutation | Produces a codon that codes for a different amino acid | | 200 |
| 4906061238 | Frameshift mutation | Result from a nucleotide addition or deletion and change the reading frame of subsequent codons | | 201 |
| 4906061239 | Structural differences between RNA and DNA | Substitution of arrival sugar for deoxyribose
Substitution of uracil for thymine
Single-stranded instead of double-stranded | | 202 |
| 4906061240 | mRNA | Carries the message from DNA in the nucleus via transcription of the gene; travels into the cytoplasm to be translated | | 203 |
| 4906061241 | tRNA | Brings in amino acids, recognizes the codon on the mRNA using its anti-codon | | 204 |
| 4906061242 | rRNA | Makes up the ribosome; enzymatically active | | 205 |
| 4906061243 | Helicase and topoisomerase | Unwind double stranded DNA | | 206 |
| 4906061244 | RNA polymerase | Binds to the TATA box within the promoter region of the gene (25 base pairs upstream from the transcribed base) | | 207 |
| 4906061245 | hnRNA | Is synthesized from the DNA template (antisense) strand | | 208 |
| 4906061246 | Post transcriptional modifications | A 7-methylguanylate triphosphate cap is added to the 5' end
A poly-A tail is added to the 3' end
Splicing is done by the snRNA and snRNP's in the splicosome. Introns are removed in a lariat structure and exons are ligated together | | 209 |
| 4906061247 | Polycistronic genes | A post translational modification that can increase variability of gene products by starting transcription in different sites within the gene leads to different gene products | | 210 |
| 4906061248 | Alternative splicing | A posy translational modification that can increase variability of gene products by combining different exonerated in a modular fashion to acquire different gene products | | 211 |
