[BIOCHEM LAB FINALS] TO2

Qualitative Analysis

What is the process of identifying chemical substances present in a sample?

Color Formation

What observable change occurs when a chemical reaction produces a colored product?

Ring Formation

What observable change occurs when a colored product develops in a ring shape?

Precipitate Formation

What observable change occurs when an insoluble solid forms during a chemical reaction?

Amino Acid

What biological molecule serves as the fundamental monomer or building block of proteins?

Amino Group

What functional group is represented by NH2 in the general amino acid structure?

Carboxyl Group

What functional group is represented by COOH in the general amino acid structure?

Alpha Carbon

What central carbon is attached to the amino group, carboxyl group, hydrogen, and R group?

Hydrogen Atom

Which atom is attached to the alpha carbon along with the amino group, carboxyl group, and R group?

R Group

What variable component determines the distinctive chemical properties of an amino acid?

Non polar, polar, basic, acidic

What four classes are presented in the amino acid classification diagrams?

Nonpolar Hydrophobic Amino Acids

Which class includes alanine, valine, leucine, isoleucine, methionine, proline, tryptophan, and phenylalanine?

Alanine (Ala, A)

Which amino acid is abbreviated Ala and represented by the one-letter code A?

Valine (Val, V)

Which amino acid is abbreviated Val and represented by the one-letter code V?

Leucine (Leu, L)

Which amino acid is abbreviated Leu and represented by the one-letter code L?

Isoleucine (Ile, I)

Which amino acid is abbreviated Ile and represented by the one-letter code I?

Methionine (Met, M)

Which amino acid is abbreviated Met and represented by the one-letter code M?

Proline (Pro, P)

Which amino acid is abbreviated Pro and represented by the one-letter code P?

Tryptophan (Trp, W)

Which amino acid is abbreviated Trp and represented by the one-letter code W?

Phenylalanine (Phe, F)

Which amino acid is abbreviated Phe and represented by the one-letter code F?

Polar Hydrophilic Amino Acids

Which class includes glycine, serine, threonine, cysteine, tyrosine, asparagine, and glutamine?

Glycine (Gly, G)

Which amino acid is abbreviated Gly and represented by the one-letter code G?

Serine (Ser, S)

Which amino acid is abbreviated Ser and represented by the one-letter code S?

Threonine (Thr, T)

Which amino acid is abbreviated Thr and represented by the one-letter code T?

Cysteine (Cys, C)

Which amino acid is abbreviated Cys and represented by the one-letter code C?

Tyrosine (Tyr, Y)

Which amino acid is abbreviated Tyr and represented by the one-letter code Y?

Asparagine (Asn, N)

Which amino acid is abbreviated Asn and represented by the one-letter code N?

Glutamine (Gln, Q)

Which amino acid is abbreviated Gln and represented by the one-letter code Q?

Polar Positively Charged Amino Acids

Which class includes histidine, lysine, and arginine?

Histidine (His, H)

Which amino acid is abbreviated His and represented by the one-letter code H?

Lysine (Lys, K)

Which amino acid is abbreviated Lys and represented by the one-letter code K?

Arginine (Arg, R)

Which amino acid is abbreviated Arg and represented by the one-letter code R?

Polar Negatively Charged Amino Acids

Which class includes aspartic acid and glutamic acid?

Aspartic Acid (Asp, D)

Which amino acid is abbreviated Asp and represented by the one-letter code D?

Glutamic Acid (Glu, E)

Which amino acid is abbreviated Glu and represented by the one-letter code E?

Tyrosine

Which amino acid is identified as the first unknown sample in the PDF?

Proline

Which amino acid is identified as the second unknown sample in the PDF?

Histidine

Which amino acid is identified as the third unknown sample in the PDF?

Arginine

Which amino acid is identified as the fourth unknown sample in the PDF?

UAA 5

Which amino acid is identified as the fifth unknown sample in the PDF?

UAA 6

Which amino acid is identified as the sixth unknown sample in the PDF?

UAA 7

Which amino acid is identified as the seventh unknown sample in the PDF?

Solubility Test

Which test compares the reported solubility of amino acid samples in hot water, HCl, NaOH, and chloroform?

Hot Water

Which heated polar solvent is used in the amino acid solubility test?

Hydrochloric Acid (HCl)

Which acidic solution is used as a solvent in the solubility test?

Sodium Hydroxide (NaOH)

Which alkaline solution is used as a solvent in the solubility test?

Chloroform

Which nonpolar solvent is included in the solubility test?

Glycine Solubility Result

What solubility results are reported for glycine in hot water, HCl, NaOH, and chloroform?

Lysine Solubility Result

What solubility results are reported for lysine in hot water, HCl, NaOH, and chloroform?

Glutamine Solubility Result

What solubility results are reported for glutamine in hot water, HCl, NaOH, and chloroform?

UAA 1 Solubility Result

What solubility results are reported for tyrosine in hot water, HCl, NaOH, and chloroform?

UAA 2 Solubility Result

What solubility results are reported for proline in hot water, HCl, NaOH, and chloroform?

Miscible

What term is used in the PDF's solubility table to describe the reported result in hot water, HCl, and NaOH?

Immiscible

What term is used in the PDF's solubility table to describe the reported result in chloroform?

Zwitterion

What type of molecule contains both positive and negative regions of charge?

Zwitterion Form

What amino acid form contains a positively charged amino group and a negatively charged carboxyl group?

Positive Charge in a Zwitterion

Which charged amino group is represented as NH3+ in the zwitterion diagram?

Negative Charge in a Zwitterion

Which charged carboxyl group is represented as COO- in the zwitterion diagram?

Zwitterion and Solubility

What property of amino acids is affected by their zwitterion form according to the PDF?

Qualitative Tests

What section introduces the chemical tests used to identify amino acids?

Ninhydrin Test

Which qualitative test detects alpha-amino acids by producing a characteristic blue-purple color?

Ruhemann's Purple

What is the name of the blue-purple product associated with the usual positive ninhydrin reaction?

Ninhydrin Blue-Purple Result

What color is produced when most alpha-amino acids react with ninhydrin?

Ninhydrin Yellow Result

What color do proline and hydroxyproline produce in the ninhydrin test?

Proline and Hydroxyproline

Which two amino acids produce a yellow color in the ninhydrin test according to the PDF?

Imino Group

Which group is identified in the PDF as responsible for the yellow ninhydrin reaction of proline and hydroxyproline?

Hydrindantin

What intermediate or reaction product is named in the PDF's simplified ninhydrin reaction description?

Ninhydrin Reaction

What reagent reacts with an amino acid to produce the characteristic ninhydrin color reaction?

Xanthoproteic Test

Which test detects aromatic amino acids through nitration with concentrated nitric acid?

Aromatic Amino Acids

Which class of amino acids is targeted by the xanthoproteic test?

Concentrated Nitric Acid

Which acid is used to nitrate susceptible aromatic rings in the xanthoproteic test?

Nitration

What chemical process produces nitrated aromatic derivatives in the xanthoproteic test?

Nitrotyrosine

What nitrated amino acid derivative is illustrated in the xanthoproteic test slide?

Xanthoproteic Yellow Result

What color indicates the initial positive xanthoproteic reaction?

Xanthoproteic Orange Result

What color develops when alkaline conditions follow the initial xanthoproteic reaction?

Heat in the Xanthoproteic Test

What condition is indicated above the reaction arrow for the xanthoproteic reaction in the PDF?

Pauly's Diazo Test

Which qualitative test detects histidine and tyrosine through formation of a colored azo compound?

Sulfanilic Acid

Which chemical forms a diazonium salt in Pauly's diazo test?

Sodium Nitrite (NaNO2)

Which reagent reacts with sulfanilic acid in the diazonium salt preparation described in the PDF?

Hydrochloric Acid in Pauly's Test

Which acid is used with sodium nitrite to form the diazonium salt?

Diazonium Salt

What reactive compound forms from sulfanilic acid, sodium nitrite, and hydrochloric acid in Pauly's test?

Alkaline Conditions in Pauly's Test

Under what conditions does the diazonium salt couple with histidine or tyrosine?

Azo Compound

What type of colored compound forms when the diazonium salt couples with histidine or tyrosine?

Azo Compound Color

What color is produced by the azo compound in Pauly's diazo test according to the PDF?

Visible Light Absorption

What property of the azo compound contributes to its red-orange appearance?

Millon's Test

Which qualitative test detects tyrosine through its phenolic group?

Phenolic Group

Which functional group of tyrosine is targeted by Millon's test?

Millon's Reagent

Which reagent reacts with tyrosine during Millon's test?

Heating in Millon's Test

What condition is specified for the reaction between tyrosine and Millon's reagent?

Millon's Positive Result

What color or precipitate is associated with a positive Millon's test in the illustrated results?

Millon's Negative Result

What observation indicates a negative Millon's test in the illustrated results?

Histidine Test

Which qualitative test uses bromine to react with the imidazole ring of histidine in an acidic solution?

Imidazole Ring

Which structural ring in histidine is targeted by the histidine test?

Bromine (Br2)

Which chemical reacts with histidine in the acidic medium described in the PDF?

Acidic Medium

Under what conditions does bromine react with the imidazole ring in the histidine test?

Brominated Histidine Derivative

What product is described when bromine reacts with histidine in an acidic solution?

Histidine Test Positive Result

What positive color is reported for the histidine test in the PDF?

Sakaguchi Test

Which qualitative test detects arginine through its guanidino group?

Guanidino Group

Which functional group of arginine undergoes the reaction described in the Sakaguchi test?

Alpha-Naphthol

Which reagent reacts with arginine in the Sakaguchi test?