Lab Final

1. Prewet the pipette tip to avoid lower delivery volumes. 2. Work at temperature equilibrium to minimize variation of volume.

1. Do not perform experiments unsupervised. 2. Wear goggles. 3. Ensure clothes cover the entire body. 4. No open-toed shoes. 5. Tie back hair.

pH reflects the concentration of hydrogen ions on a logarithmic scale. Acids partially ionize and donate hydrogen, thus lowering the pH of the solution.

<p>Keeping a clean workspace is important for preventing contamination and ensuring accurate experimental results.</p> Signup and view all the answers

<p>The acceptance of hydrogen ions, affecting pH</p> Signup and view all the answers

<p>The pKa value, with smaller pKa indicating stronger acids and larger pKa indicating stronger bases</p> Signup and view all the answers

<p>Resist pH changes, maintaining stability</p> Signup and view all the answers

<p>The pH change during acid-base reactions</p> Signup and view all the answers

<p>The concentration of absorbing species</p> Signup and view all the answers

<p>Light absorption</p> Signup and view all the answers

<p>Various methods, such as the Bradford method</p> Signup and view all the answers

<p>Column, ion-exchange, size-exclusion, affinity, and high-performance liquid chromatography</p> Signup and view all the answers

<p>Molecular mass and sequence amino acids</p> Signup and view all the answers

<p>Charged fragments</p> Signup and view all the answers

<p>Peptide synthesis</p> Signup and view all the answers

<p>Size, as demonstrated with hemoglobin and vitamin B12 in the lab</p> Signup and view all the answers

<p>PCR is used to amplify DNA segments using DNA polymerase, primers, dNTPs, and Taq polymerase.</p> Signup and view all the answers

<p>The Sanger Method uses ddNTPs to interrupt DNA synthesis and determine DNA sequences.</p> Signup and view all the answers

<p>DNA fingerprinting uses short tandem repeats (STRs) for paternity testing and restriction endonucleases to cleave DNA. The process involves isolating DNA, cutting with enzymes, gel electrophoresis, and Southern blotting.</p> Signup and view all the answers

<p>X-ray crystallography produces electron density maps from protein crystals.</p> Signup and view all the answers

<p>NMR measures nuclear spin to capture protein structure dynamics.</p> Signup and view all the answers

<p>Carbohydrate purification methods include fractional precipitation, ion-exchange, size exclusion, and affinity chromatography.</p> Signup and view all the answers

<p>Carbohydrate analysis methods include traditional chemical and enzymatic approaches, mass spectrometry, and high-resolution NMR spectroscopy.</p> Signup and view all the answers

<p>Solid-phase oligosaccharide synthesis yields defined oligosaccharides useful in exploring lectin-oligosaccharide interactions.</p> Signup and view all the answers

<p>DNA cloning involves obtaining a DNA segment, using cloning vectors, joining DNA fragments, moving recombinant DNA to host organisms, and selecting host cells containing recombinant DNA.</p> Signup and view all the answers

<p>Gel electrophoresis techniques are used to estimate the number of different proteins in a mixture, degree of purity, isoelectric point, and approximate molecular weight of proteins in a sample.</p> Signup and view all the answers

<p>SDS electrophoresis uses a detergent to give all proteins a similar charge-to-mass ratio and separates proteins by molecular weight.</p> Signup and view all the answers

<p>Two-dimensional electrophoresis combines isoelectric focusing and electrophoresis to determine the isoelectric point and separate proteins by molecular weight, providing a more sensitive technique for protein analysis.</p> Signup and view all the answers

<p>The shared proteins between species E and B, C, and D indicate a closer evolutionary relationship, leading to the placement of species E on its own branch in the phylogenetic tree.</p> Signup and view all the answers

<p>Western blotting involves transferring proteins from a gel to a membrane and using antibodies to detect specific proteins, allowing for the identification and quantification of target proteins.</p> Signup and view all the answers

<p>The Western blotting process includes steps such as adding primary and secondary antibodies, using enzyme-linked secondary antibodies, and adding colorimetric substrate to visualize the protein bands.</p> Signup and view all the answers

<p>Troubleshooting steps for Western blotting include addressing issues such as extra bands, vertical lines, halo bands, absence of bands, presence of only prestained standards, bands with white circles or holes, smiling or frowning bands, and pale bands.</p> Signup and view all the answers

<p>Melting curves can be used to estimate the C-G and T-A ratio of DNA by solving for the denaturation temperature ($T_m$), which provides insights into the stability and composition of DNA.</p> Signup and view all the answers

<p>The lab involved the extraction and denaturation of proteins from muscle tissue, followed by gel electrophoresis to separate the proteins by molecular weight.</p> Signup and view all the answers

<p>The lab included the use of Western blotting to identify myosin light chain proteins in the fish muscle extract.</p> Signup and view all the answers

<p>Troubleshooting steps were applied during the lab to address issues related to Western blotting, such as the appearance of extra bands and pale bands.</p> Signup and view all the answers

<p>Melting curves were used in the lab to estimate the C-G and T-A ratio of DNA by solving for the denaturation temperature ($T_m$), providing insights into the composition and stability of DNA.</p> Signup and view all the answers

<p>The gene encoding the protein of interest is fused with a gene for an epitope tag. The protein is then precipitated by complexing it with an antibody that binds to the epitope. This immunoprecipitation helps identify associated proteins. The precipitated proteins can then be separated using affinity chromatography, and the proteins eluted from the column are identified by mass spectrometry.</p> Signup and view all the answers

<p>The CRISPR/Cas complex consists of guided RNAs, trans-activating CRISPR RNA (tracrRNA), and one or more Cas proteins. The complex binds and destroys invading bacteriophage DNA through the action of the Cas protein nuclease.</p> Signup and view all the answers

<p>CRISPR sequences consist of regularly spaced short repeats in bacterial genomes, while Cas proteins are nucleases or components of the immune system that have evolved to allow bacteria to survive infection by bacteriophages.</p> Signup and view all the answers

<p>Current CRISPR technology requires one Cas protein (Cas9) to cleave DNA and a single guide RNA (sgRNA) to pair with the target DNA sequence and activate the nuclease domains. Cas9 has two separate nuclease domains, and the sgRNA is made of gRNA and tracrRNA fused into one RNA.</p> Signup and view all the answers

<p>Mutation can be introduced by recombination when a DNA fragment enters a cell with CRISPR/Cas9 plasmids. CRISPR/Cas9 can be combined with other approaches such as RNA-Seq for additional information in research, medicine, genetic screening, and more.</p> Signup and view all the answers

<p>Lipids are generally separated by differences in polarity or solubility in nonpolar solvents. The methods include adsorption chromatography using polar materials like silica, and gas chromatography to resolve mixtures of volatile lipid derivatives.</p> Signup and view all the answers

<p>Neutral lipids are extracted with ethyl ether, chloroform, or benzene, while membrane lipids are extracted by ethanol or methanol. A commonly used extractant for membrane lipids is a mixture of chloroform, methanol, and water (1:2:.08).</p> Signup and view all the answers

<p>Mass spectrometry allows the analysis of crude mixtures of lipids without prefractionation. It can determine the length of a hydrocarbon chain or positions of double bonds but not cis &amp; trans.</p> Signup and view all the answers

<p>Specific hydrolysis involves cleaving ester-linked fatty acids with mild acid or alkaline treatment. It can also cleave amide-bound fatty acids from sphingolipids under harsher hydrolysis conditions. Phospholipases specific for one of the bonds in a phospholipid generate simpler compounds.</p> Signup and view all the answers

<p>Guided RNAs and tracrRNA play a role in pairing with the target DNA sequence and activating the nuclease domains of the Cas proteins in the CRISPR/Cas complex.</p> Signup and view all the answers

<p>The Cas protein nuclease within the CRISPR/Cas complex binds and destroys invading bacteriophage DNA by cleaving it, thereby providing immunity to the bacterial host.</p> Signup and view all the answers

<p>Mass spectrometry in lipid analysis allows the determination of the length of a hydrocarbon chain and the positions of double bonds, providing valuable structural information about lipids.</p> Signup and view all the answers

<p>To prevent lower delivery volumes</p> Signup and view all the answers

<p>To minimize variation of volume</p> Signup and view all the answers

<p>Concentration of hydrogen ions</p> Signup and view all the answers

<p>Pull the tip straight out</p> Signup and view all the answers

<p>The strength of the acid or base</p> Signup and view all the answers

<p>Concentration of absorbing species</p> Signup and view all the answers

<p>Light absorption</p> Signup and view all the answers

<p>Measuring protein concentration</p> Signup and view all the answers

<p>Separating molecules based on size</p> Signup and view all the answers

<p>Molecular mass</p> Signup and view all the answers

<p>Sorting and measuring charged fragments</p> Signup and view all the answers

<p>Peptide synthesis</p> Signup and view all the answers

<p>pH change during acid-base reactions</p> Signup and view all the answers

<p>To maintain stability of pH</p> Signup and view all the answers

<p>Size-exclusion and affinity</p> Signup and view all the answers

<p>Charged fragments</p> Signup and view all the answers

<p>To determine the RNAs transcribed from a genome under specific conditions</p> Signup and view all the answers

<p>To identify associated proteins</p> Signup and view all the answers

<p>Cas protein and single guide RNA (sgRNA)</p> Signup and view all the answers

<p>To determine the length of a hydrocarbon chain</p> Signup and view all the answers

<p>It provides heat stability to the DNA polymerase</p> Signup and view all the answers

<p>To cleave DNA at specific sites</p> Signup and view all the answers

<p>With ethyl ether, chloroform, or benzene</p> Signup and view all the answers

<p>Sanger Method</p> Signup and view all the answers

<p>To destroy invading bacteriophage DNA</p> Signup and view all the answers

<p>To separate DNA fragments by size</p> Signup and view all the answers

<p>To visualize endogenous proteins</p> Signup and view all the answers

<p>To produce electron density maps from protein crystals</p> Signup and view all the answers

<p>By turning lipids into gas for elution</p> Signup and view all the answers

<p>To capture protein structure dynamics</p> Signup and view all the answers

<p>To pair with the target DNA sequence</p> Signup and view all the answers

<p>Simpler compounds</p> Signup and view all the answers

<p>Solid-phase oligosaccharide synthesis</p> Signup and view all the answers

<p>To isolate specific DNA segments</p> Signup and view all the answers

<p>Determining deleting or altering a protein to determine its function</p> Signup and view all the answers

<p>To separate the precipitated proteins</p> Signup and view all the answers

<p>To separate molecules based on size</p> Signup and view all the answers

<p>To analyze carbohydrate structures</p> Signup and view all the answers

<p>To amplify DNA segments</p> Signup and view all the answers

<p>For paternity testing</p> Signup and view all the answers