CHM2030 Introduction to General, Organic, and Biological Chemistry
TEST EXAMPLES
Part I. True (1)/False (2) questions

Mark (1) for True and (2) for False questions
(T) Margarine is formed by adding hydrogen to "reduce" the double bonds of a vegetable oil.

(T) All unsaturated hydrocarbons can be saturated with hydrogen and reduced.

(T) All unsaturated hydrocarbons can be saturated with water to generate alcohols.

(F) The above reaction is a reduction reaction.

(F) Alkanes, alkenes, and alkynes are burned to produced different products.

(T) Alcohols can be formed by hydration of alkenes.

(F) Polyethylene can be easily formed from ethylene even without catalyst.

Please refer to the structure in the lecture note of the compounds below.
(T) Aspirin, ibuprofen, and acetaminophen all contain an aromatic structure.
(T) Aspirin contain a carboxylate functional group.
(T) Aspirin is an ester of salicylic acid.
(F) acetominophen is an ester.

(T) Petroleum cracking process is to break down or rearrange natural hydrocarbons into more useful hydrocarbons.

(T) Hydrocarbons are hydrophobic.

(T) Both water and alcohols can be involved in H-bonding interaction.

(T) Both aldehydes and ketones can be formed from oxidation of alcohols.

(T) Both aldehydes and ketones can be formed indirectly from alkenes because alcohols can be prepared from alkenes.

(T) Primary alcohols can be oxidized into aldehydes, then further oxidized into carboxylic acids.

(F) Secondary alcohols can be oxidized into ketones, then further oxidized into carboxylic acids.

(F) Both aldehydes and ketones can be oxidized into carboxylic acids.

(F) Tertiary alcohols can be oxidized to carboxylic acid.

(F) Thiols give very pleasant odors.

(T) Many aldehydes and ketones give very good flavors, such as the flavors of almond, cinnamon, vanilla, etc.

(T) An ester is formed by reacting an alcohol with a carboxylic acid.

(F) A polyester is formed by reacting unlimited amount of an alcohol and a carboxylic acid.

(F) An amino acid contains an amide and an acid functional groups.

(F) Reaction of a carboxylic acid and an amine can produce polymer, such as nylon-66.

(T) A polyester can be formed by reacting a diol with a dicarboxylic acid

(T) The >C=O group can be involved in H-bonding with an amine.

(T) A peptide bond formed between two amino acids is an amide bond.

(F) The essential amino acids the we need are all D-form amino acids.

(T) The L-form and D-form amino acids have the same chemical properties.

(T) MSG is a salt of an amino acid.
(F) Amino acids are always negative because H+ is given away by their carboxylic acid group.

(F) At pH = pI of an amino acid, the amino acid has no charge.

(F) At pH = pI of an amino acid, the amino acid is positively charged.

(F) At pH = pI of an amino acid, the amino acid is negatively charged.

(T) At pH = pI of an amino acid, the amino acid has both a positive and a negative charge.

(T) A molecule possessing both a positive and a negative charge is called a zwitterion.

(F) At pH equals to the isoelectric point of an amino acid, the amino acid has no charge on it at all.

(T) The cause of sickle cell anemia is because a mutation at an amino acid of hemoglobin. This change results in hemoglobin coagulation through hydrophobic interaction.

(T) The sweetener NutraSweet® is a dipeptide (Asp-Phe) and is much sweeter than sucrose. However, it cannot be used for people with phenylketonuria.

(T) The commonly used antibiotic bacitracin (an ingredient in triple antibiotic ointment) is a peptide.

(T) The order of amino acids in proteins is called the primary structure of proteins.

(F) There are three different kinds of secondary structures for protein, a , b , and g structures.

(T) The tertiary structure of a protein is the 3-D structure we are talking about proteins.

(T) The quaternary structure of proteins is the packing of subunits of proteins, such as packing of 2a and 2b subunits into a hemoglobin molecule.

(F) All keratins contain a-helical structure.

(T) Heavy metal ions can react with the S on Cys to cause denaturation of proteins.

(F) All proteins are denatured at higher temperatures, like at 80 deg-C.

(F) There is no functional enzyme at pH 3, since all proteins under such acidic conditions are denatured.

(T) Disulfide bonds are formed in protofibril, which makes hair, horn, nails, etc. very strong.

(F) The two dipeptides Asp-Phe and Phe-Asp have the same properties.

(F)  Proteins cannot be changed any more after they have been synthesized at the stage of translation.

(F) Hemoglobin and myoglobin catalyze oxygen transport in our body, and are two best examples of enzymes.

(F) Lactose intolerance is due to the lack of the enzyme galactase, thus cannot convert galactose further. Note: Galactose is a product when lactose is hydrolyzed.

(T) Both starch and cellulose are polymers of glucose.

(F) Because proteins are soluble in water, hydrophobic interactions within and between protein molecules are impossible.

Some examples about nucleic acids:
(F) The complementary DNA strand of 3’-A-T-G-C-A-T-5’ is 3’-T-A-C-G-T-A-5’

(F) DNA replication is catalyzed by the enzyme DNA replicase.

(F) The technique PCR widely used in forensic identification is called "Protein Chain Reaction".

(T) One difference between DNA and RNA is that the oxygen on the #2 position of ribose is removed in DNA.

(F) All the three forms of DNA, the A, B, and Z forms, are right-handed.

(F) Gene is a piece of DNA that is long enough to form a double helix.

(F) The production of complementary RNA strand from DNA strand is called "duplication".

(T)  Proteins are synthesized in ribosomes.

(F) Messenger RNA delivers amino acid during translation for protein synthesis.

(T) Recombinant DNA techniques is described as "transplantation of gene from one organism into another".

(F) In sickle cell hemoglobin, the mutation on the single amino acid is attributed to the change of all the three base pairs of the genetic code.

(F) The two strands of DNA double helix are held tightly together by covalent bonds.

(T)  Nucleic acids are formed by linking nucleotides together with phosphodiester bonds.

Part II. Multiple Choice Questions 

Match the functional groups with their names (Please refer to the structure in Table 11.2.)
            (1) –COOH    (2) –CHO    (3) –CO–    (4) –COOR    (5) –CONHR
(5) An amide
(3) A ketone
(2) An aldehyde
(1) A carboxylic acid
(4) An ester

Match the functional groups with their names (Please refer to the structure in Table 11.2.)
            (1) C–C    (2) C=C    (3) C–X    (4) CtC    (5) C–O–C
(2) An alkene
(4) An Alkyne
(5) An ether
(1) An alkane
(3) A halocarbone

(3)  The sweetener NutraSweet® is the dipeptide ______ which is much sweeter than sucrose.
            (1) Phe-Asp    (2) Glu-Phe    (3) Asp-Phe    (4) Phe-Glu    (5) Cys-Phe

(4) When both hydrogens of a water molecule is replaced with a hydrocarbon chain, it forms
            (1) a ketone (2) an aldehyde (3) an ester (4) an ether (5) a carbohydrate

(4) Which one can be formed by oxidation of alcohol?
            (1) ketone (2) aldehyde (3) carboxylic acid (4) All of them! (5) None of them!

(2)  Aspirin is formed by adding acetic acid to salicylic acid, in which the phenol group of salicylic acid is modified by acetic acid. This reaction is called __________.
            (1) aspirination (2) esterification (3) etherification (4) acetylation

(1)  Which intermediate during alcohol metabolism that may cause liver cirrhosis?
            (1) aldehyde (2) acetone (3) carboxylic acid (4) ester (5) None of them!

(4) Which compound cannot form H-bond with water at all?
            (1) ketones (2) carboxylic acids (3) aldehydes (4) hydrocarbons (5) sugar

(1) Soaps can be formed from one of the following compounds containing a long chain.
            (1) carboxylic acids (2) ketones (3) aldehydes (4) hydrocarbons (5) sugar

(4)  Which is the ion in "hard water" that disables the washing power of soaps?
            (1) Na+ (2) Mg2+ (3) Al3+ (4) Ca2+ (5) K+

(4) Which bond can be hydrolyzed?
            (1) ester (2) amide (3) peptide (4) All of them! (5) None of them!

(4) Water is released during the formation of which compound?
            (1) ester (2) amide (3) peptide (4) All of them! (5) None of them!

(1) Reaction of a dicarboxylic acid with a diol can produce ______.
            (1) polyester (2) dicarboxyester (3) polyamide (4) dipeptide

(3) Which amino acid has a hydrophobic side chain?
            (1) histidine (2) cysteine (3) phenylalanine (4) arginine (5) aspartic acid

(2) Which of the above amino acid contain a sulfur atom?

(3) Which is the amino acid found in relatively large amount in turkey, which makes you feel drowsy after it is converted into serotonin?
            (1) tyrosine (2) methionine (3) tryptophan (4) serine

(2) Glucose must be phosphorylated to give glucose-6-PO4 during its metabolism. However, the equilibrium constant is too small to produce reasonable amount of the product. A high-energy compound is needed to drive the equilibrium to form glucose-6-PO4. What is the high-energy compound?
            (1) phospholipid (2) ATP (3) ADP (4) phosphocreatine (5) phosphotidylcholine

Connect the compounds with their functions.
(2) penicillin                     (1) causing increase of blood pressure
(3) enkephalins                 (2) inhibitor for cell wall synthesis
(1)  angiotensin II             (3) associated with relief pain
(5) thrombin                    (4) triggering pain, lowering blood pressure, and involved in inflammation.
(4) bradykinin                  (5) involved in blood clotting

(3) Salts with both positive and negative charges present in the same molecule are called
            (1) a neutral ion (2) an isoelectric ion (3) a zwitterion (4) a twisterion

(2) The "starting codon" encodes the amino acid _____, which encodes the starting point of all proteins in living systems.
            (1) aspartic acid (2) methionine (3) serine (4) startine (5) hitidine

(3) Alpha helix (a -helix) structure is _______.
            (1) zigzaged    (2) left-handed    (3) right-handed.    (4) circular

(3) In a -helix, there are ______ residues (amino acids) per turn.
            (1) 1.2 (2) 2.4 (3) 3.6 (4) 4.8 (5) 6.0

(4) Collagen has a _______ structure.
            (1) a -keratin (2) a -helix (3) double helix (4) triple helix (5) collagenase

(1) At what pH is glycine positively charged relative to its IP value?
            (1) pH < IP (2) pH = IP (3) pH > IP

The mutation of a single amino acid in hemoglobin can result in sickle cell anemia. The difference between normal hemoglobin and sickle cell hemoglobin is the replacement of a single base in the hemoglobin gene, which is the change of (2) into (4).
            (1) aspartic acid (2) glutamic acid (3) histidine (4) valine (5) leucine

(5) Protein tertiary structure (3-D structure) can involve
            (1) hydrogen bonding (2) hydrophobic interaction (3) disulfide bond (4) salt bridge (5) All of them.

(1) Which is the enzyme that controls the buffer system in the blood?
            (1) carbonic anhydrase (2) bufferase (3) carboxypeptidase (4) urease (5) rennin

(2) Which of the followings cannot be hydrolyzed by certain enzymes in our body?
            (1) amylose     (2) cellulose     (3) glycogen     (4) All of them can be hydrolyzed.     (5)All of them cannot be hydrolyzed.

(3) Which one is an incorrect statement?
            (1) Essential amino acids cannot be synthesized in the body.
            (2) A common function of vitamins is simply to act as an enzyme cofactor.
            (3) Potassium ions can substitute for sodium ions in the body.
            (4) Some trace elements, such as Cu2+ and Zn2+, can act as enzyme cofactors.

(3)  Which is the enzyme in your saliva that can hydrolyze starch to give sweet taste of bread and rice upon chewing.
            (1) starchase (2) glucosase (3) amylase (4) amyloid (5) lactase

(5) Which factors can cause protein denaturation?
            (1) radiations (2) reduction (3) heavy metal ions (4) none of 1–3 (5) All of 1–3.

(5) There are ____ ways to link 4 amino acids together to form a tetrapeptide.
            (1) 8 (2) 12 (3) 16 (4) 20 (5) 24
            How amny way are there to link 5 amino acids together to form a pentapeptide?  (5! ways)

(3) Enzymes have the followings properties EXCEPT
            (1) They are very specific.
            (2) They may require cofactors.
            (3) They change chemical equilibrium to enhance the catalysis.
            (4) they do not change by the reaction they catalyze.
            (5) They are involved in metabolisms in our body.

(4) The first enzyme used to demonstrate that enzymes were proteins was:
            (1) trypsin (2) amylase (3) hemoglobin (4) urease (5) protease

Some examples about nucleic acids:
(1) The ordered sequence of steps in the central dogma of genetic information transmission is
            (1) replication, transcription, translation.         (2) translation, transcription, replication.
            (3) replication, translation, transcription.         (4) translation, replication, transcription.

(4) The RNA strand transcribed from the strand of DNA molecule 3’–G–A–T–T–C–G–5’ would be
            (1) 3’–C–T–A–A–G–C–5’                          (2) 3’–C–U–A–A–G–C–5’
            (3) 5’–C–T–A–A–G–C–3’                          (4) 5’–C–U–A–A–G–C–3’

(3) The type of RNA molecules that carry the information to ribosomes for  protein synthesis in cells is
            (1) rRNA. (2) cRNA. (3) mRNA. (4) tRNA.

(2) In nucleic acids, the riboses are linked by a
            (1) peptide bond. (2) phosphoester bond. (3) ester bond. (4) nucleic bond.

(1)  The scientist who actually obtained the sharpest X-ray diffraction patterns of DNA:
            (1) Rosalind Franklin (2) Erwin Chargoff (3) Linus Pauling (4) James Watson (5) Francis Crick

(5) The base found only in RNA is:
            (1) A (2) T (3) G (4) C (5) U

(3) In the normal B-form DNA structure, there are ____ base pairs per turn.
            (1) 5 (2) 8 (3) 10 (4) 15 (5) 20