ChTLE 2024 Organic Chemistry Pre-Board Exam (2/3)

The two strands of DNA are said to be:

A. oppositely charged

B. complementary

C. identical

D. partners

B.

The amino acid sequence of a polypeptide chain comprises the _____ structure of the protein.

A. primary

B. secondary

C. tertiary

D. quarternary

A.

An amino acid with a polar R group.

A. Cysteine

B. Phenylalanine

C. Leucine

D. Valine

A.

An amino acid with a basic R group.

A. Alanine

B. Arginine

C. Proline

D. Glutamine

B.

An amino acid that is electrically neutral at pH 5.

A. Aspartic acid

B. Histidine

C. Glycine

D. Threonine

D.

An amino acid that will move towards the cathode at pH 10.

A. Glutamic acid

B. Tyrosine

C. Alanine

D. Valine

C.

A test for the presence of benzene ring in protein.

A. Biuret

B. Millon's

C. Hopkin's Cole

D. Xanthoproteic

D.

Protein present in bones.

A. collagen

B. fibroin

C. elastin

D. keratin

A.

Protein in grains.

A. lactalbumin

B. myosin

C. leucasin

D. globulin

C.

Simple protein in blood.

A. edestin

B. fibrinogen

C. myosin

D. glutenin

B.

An alkaloidal reagent that is used in the treatment of burns.

A. tannic acid

B. picric acid

C. phosphotungstic acid

D. phosphomolybdic acid

B.

A conjugated protein with colored pigment.

A. chromoprotein

B. glycoprotein

C. nucleoprotein

D. phosphoprotein

A.

The Xanthoproteic test is a test for the presence of:

A. Tryptophan

B. Serine

C. Tyrosine

D. Threonine

C.

A color test for protein that uses glyoxylic acid as reagent.

A. Millon's

B. Xanthoproteic

C. Ninhydrin

D. Hopkin's Cole

D.

A dipolar ion formed when amino acid undergoes self protonation.

A. anion

B. cation

C. zwitterion

D. AOTA

C.

DNA is the genetic material of the cells. The building block of DNA are:

A. amino acids

B. monosaccharides

C. disaccharides

D. nucleotides

D.

Enzymes are molecules that speed up chemical reactions. All enzymes are:

A. carbohydrates

B. nucleic acids

C. proteins

D. lipids

C.

When proteins are broken down by enzymes, the products are:

A. amino acids

B. carbohydrates

C. fatty acids

D. nucleic acids

A.

A nucleotide contains _____.

A. sulfur

B. nitrogen base

C. 6-carbon sugar

D. all of the above

B.

The structure of DNA was described by_____.

A. Watson and Crick

B. Mendel

C. Redi

D. Chargaff

A.

Which of the following vitamins are all fat soluble.

A. ABCD

B. ACDE

C. ADEK

D. BCDE

C.

Defficiency of this vitamin will cause scurvy.

A. Vit A

B. Vit B

C. Vit C

D. Vit D

C.

Vitamin B6 is also known as:

A. Niacin

B. Pyridoxin

C. Thiamin

D. Rivoflavin

B.

A vitamin that function as an antioxidant.

A. Vit A

B. Vit B

C. Vit C

D. Vit D

A.

Phylloquinone is commonly known as:

A. Vit B3

B. Vit K

C. Vit F

D. Vit H

B.

The percentage of A + G in DNA equals_____.

A. 25%

B. 50%

C. 80%

D. 100%

B.

The nucleotide of DNA have __________ bases.

A. purine

B. pyrimidine

C. either A or B

D. neither A or B

C.

The process of copying DNA molecule.

A. translation

B. reproduction

C. replication

D. transcription

C.

A new copy of a DNA molecule is precisely synthesized during a process called:

A. translation

B. transcription

C. replication

D. reproduction

A.

Which form of RNA acts as a blueprint for polypeptide biosynthesis by the ribosome?

A. mRNA

B. tRNA

C. rRNA

D.NOTA

A.

The preparation of alkyl halide that obeys Markovnikov's rule.

A. Hydrogenation

B. Halogenation

C. Hydrohalogenation

D. Hydration

C.

The solvent used for the preparation of Grignard reagent.

A. Alcohol

B. Ether

C. Acid

D. Ester

B.

Which of the following alcohol will react faster with HBr?

A. n-butanol

B. 2-methyl-1-propanol

C. 2-butanol

D. 2-methyl-2-propanol

D.

An industrial source of alcohol.

A. Coal

B. Fats

C. Sugar

D. Ethers

C.

The enzyme that aids in the fermentation of sugar to alcohol.

A. Diastase

B. Zymase

C. Maltase

D. Glucosidase

B.

Which method is not used in the preparation of simple alcohol?

A. Hydration of alkenes

B. Hydrolysis of alkyl halides

C. Fermentation of sugar

D. Oxidation of alkenes

C.

The method of preparation that gives high percentage of alcohol.

A. Diborane method

B. Hydrolysis

C. Sulfonation

D. Reduction

A.

A toxic compound formed by distillation of ethylene glycol.

A. Diethylene glycol

B. Diethyl ether

C. Ethylene oxide

D. Dioxane

A.

Which compound has the highest density?

A. Fluorobutane

B. 2-methyl-1-iodopentane

C. Chloropentane

D. Bromohexane

B.

Alcohol act as an acid if it reacts with;

A. HBr

B. CH3ONa

C. K

D. NaOH

C.