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Organic Chemistry Test

Description: This test contains 25 multiple choice questions on the topics from organic chemistry.
Number of Questions: 28
Created by:
Tags: Biomolecules dyes polymers etc. Some Important Polymers Proteins Dyes
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Among the following biomolecules, ___________ is a neurotransmitter.

  1. Abamectin

  2. Abietic acid

  3. Acetic acid

  4. Acetylcholine


Correct Option: D
Explanation:

The chemical compound acetylcholine is a neurotransmitter in both the peripheral nervous system (PNS) and central nervous system (CNS) in many organisms including humans. Acetylcholine is one of many neurotransmitters in the autonomic nervous system (ANS) and the only neurotransmitter used in the motor division of the somatic nervous system.

Which among the following is a nonessential amino acid?

  1. Isoleucine

  2. Leucine

  3. Lysine

  4. Asparagine


Correct Option: D
Explanation:

Asparagine is one of the 20 most common natural amino acids on Earth. It has carboxamide as the side-chain's functional group. It is a nonessential amino acid. Its codons are AAU and AAC.

Which among the following is a group of self-extinguishing materials?

  1. Polysiloxane

  2. Polycarbonates

  3. Polysulfides

  4. Polyether


Correct Option: B
Explanation:

Polycarbonates are transparent, self-extinguishing materials. They possess properties like crystalline thermoplasticity, high impact strength, good thermal and oxidative stability. They can be used in machinery, auto-industry and medical applications. For example, the cockpit canopy of F-22 Raptor is made of high optical quality polycarbonate.

Which among the following biomolecules is a crystalline pentose alcohol?

  1. Actin

  2. Adenosine

  3. Adenylate cyclase

  4. Ribitol


Correct Option: D
Explanation:

Ribitol is a crystalline pentose alcohol formed by the reduction of ribose. It occurs naturally in the plant Adonis vernalis, as well as in the cell walls of Gram positive bacteria .It also contributes to the chemical structure of riboflavin.

_______ is used as a pH indicator in titrations.

  1. Martius yellow

  2. Methyl orange

  3. Methyl red

  4. Naphthol Green B


Correct Option: B
Explanation:

Methyl orange is a pH indicator frequently used in titrations because of its clear colour change. As it changes colour at the pH of a mid-strength acid, it is usually used in titrations for acids.

Which of the following amino acids plays its role in the urea cycle?

  1. Methionine

  2. Taurine

  3. Ornithine

  4. Histidine


Correct Option: C
Explanation:

Ornithine is an amino acid that plays a role in the urea cycle. L-Ornithine is one of the products of the action of the enzyme arginase on L-arginine, creating urea. Therefore, ornithine is a central part of the urea cycle, which allows for the disposal of excess nitrogen.

The dye used to stain cartilage in bone specimens is

  1. Alcian blue

  2. Alizarine Yellow R

  3. Red 2G

  4. Acid dyes


Correct Option: A
Explanation:

Alcian blue stain – used to stain cartilage. Cheapest form available works fine.

This ____________ non-essential amino acid has a polar side group.

  1. Arginine

  2. Tyrosine

  3. Serine

  4. Selenocysteine


Correct Option: B
Explanation:

Tyrosine is one of the 20 amino acids that are used by cells to synthesize proteins. Its codons are UAC and UAU. It is a non-essential amino acid with a polar side group.

The carboxylate anions of ________ amino acids are important neurotransmitters.

  1. Proline

  2. Glutamine

  3. Glutamic acid

  4. Cysteine


Correct Option: C
Explanation:

Glutamic acid is one of the 20 proteinogenic amino acids, and its codons are GAA and GAG. It is a non-essential amino acid. The carboxylate anions and salts of glutamic acid are known as glutamates. In neuroscience, glutamate is an important neurotransmitter that plays a key role in long-term potentiation and is important for learning and memory.

The codon UGG is the standard genetic code for ______ amino acids.

  1. Aspartic acid

  2. Valine

  3. Tryptophan

  4. Threonine


Correct Option: C
Explanation:

Tryptophan is one of the 20 standard amino acids, as well as an essential amino acid in the human diet. It is encoded in the standard genetic code as codon UGG.

Which of the following polymers contains monomers joined by peptide bonds?

  1. Polyester

  2. Polyamide

  3. Polyurethane

  4. Polyurea


Correct Option: B
Explanation:

A polyamide is a polymer containing monomers of amides joined by peptide bonds. They can occur both naturally and artificially, examples being proteins, wool and silk, and can be made artificially through step-growth polymerization or solid-phase synthesis, examples being nylons, aramids, and sodium poly(aspartate).

The reaction of dianhydrides with diamines gives ________.

  1. Aromatic polyimide

  2. Aromatic polysulfides

  3. Polyethersulfone (PES)

  4. Aromatic polyether


Correct Option: A
Explanation:

Aromatic polyimide are synthesized by the reaction of dianhydrides with diamines, for example, pyromellitic anhydride with ''p''-phenylenediamine. It can also be accomplished using diisocyanates in place of diamines.

Which among the following dyes is a lysochrome?

  1. Sudan II

  2. Titan yellow

  3. Chrysoine resorcinol

  4. Orange G


Correct Option: A
Explanation:

Sudan II (C18H16N2O) is a lysochrome (fat-soluble dye) azo dye used for staining of triglycerides in frozen sections, and some protein bound lipids, and lipoproteins on paraffin sections. It has the appearance of red powder with melting point 156-158 °C and maximum absorption at 493(420) nm.

In ________ polymers, the repeating units are joined together by glycosidic bonds.

  1. Polyelectrolytes

  2. Polysaccharides

  3. Polypeptides

  4. Polynucleotide


Correct Option: B
Explanation:

Polysaccharides are polymeric carbohydrate structures, formed of repeating units (either mono- or di-saccharides) joined together by glycosidic bonds. These structures are often linear, but may contain various degrees of branching. Polysaccharides are often quite heterogeneous, containing slight modifications of the repeating unit.

Which of the following polymers is widely used in car tyres?

  1. Acrylonitrile butadiene styrene

  2. Styrene-Butadiene

  3. Nitrile rubber

  4. Styrene acrylonitrile resin


Correct Option: B
Explanation:

Styrene-Butadiene or Styrene-Butadiene-Rubber (SBR) is a synthetic rubber copolymer consisting of styrene and butadiene. It has good abrasion resistance and good aging stability when protected by additives, and is widely used in car tyres, where it may be blended with natural rubber.

The exoskeletons of arthropods are composed of ________ polymer.

  1. Starch

  2. Glycogen

  3. Cellulose

  4. Chitin


Correct Option: D
Explanation:

Chitin is a long-chain polymer of a N-acetylglucosamine, a derivative of glucose, and is found in many places throughout the natural world. It is the main component of the cell walls of fungi, the exoskeletons of arthropods such as crustaceans (e.g., crabs, lobsters and shrimps) and insects, the radulas of mollusks, and the beaks of cephalopods, including squid and octopuses.

Egg ovalbumin and milk casein are the examples of _______ proteins.

  1. Structural proteins

  2. Motor proteins

  3. Signalling proteins

  4. Storage proteins


Correct Option: D
Explanation:

These proteins contain energy, which can be released during metabolism processes in the organism. Egg ovalbumin and milk casein are such proteins. Almost all proteins can be digested and used as a source of energy and building material by other organisms.

Which of the following varieties of polyethylene is used for natural gas and offshore oil applications?

  1. Ultra-high-molecular-weight polyethylene

  2. High-density polyethylene

  3. Cross-linked polyethylene

  4. Medium Density Polyethylene


Correct Option: C
Explanation:

Cross-linked polyethylene, is a form of polyethylene with cross-links. It is formed into tubing, and is used predominantly in hydronic radiant heating systems, domestic water piping and insulation for high tension (high voltage) electrical cables. It is also used for natural gas and offshore oil applications,  transportation of chemicals, and transportation of sewage and slurries.

The amino acid necessary for the optimal growth of infants is

  1. Glutathione

  2. Histidine

  3. Isoleucine

  4. L-arginine


Correct Option: C
Explanation:

Isoleucine is necessary for the optimal growth of infants and for nitrogen balance in adults.

Which of the following amino acids supports healthy ageing and cellular rejuvenation?

  1. L-carnosine

  2. Leucine

  3. L-theanine

  4. Lysine


Correct Option: A
Explanation:

L-carnosine supports healthy ageing and cellular rejuvenation by its effects on two mechanisms: glycosylation and free radical damage.

Which of the following amino acids promotes proper blood glucose levels from dietary protein?

  1. Alanine

  2. Asparagine

  3. Carnosine

  4. Citrulline


Correct Option: A
Explanation:

Alanine is necessary for the promotion of proper blood glucose levels from dietary protein. It stimulates lymphocyte production and may help people who have immune suppression. It also strengthens the immune system by producing antibodies.

The amino acid needed for the metabolism of fats and fatty acids in the body is

  1. Phenylalanine

  2. Proline

  3. Serine

  4. Taurine


Correct Option: C
Explanation:

Serine is needed for the metabolism of fats and fatty acids, muscle growth and a healthy immune system.

Serotonin is is a neurotransmitter._________ amino acid is important for the its production.

  1. Threonine

  2. Tryptophan

  3. Tyrosine

  4. Valine


Correct Option: B
Explanation:

Tryptophan is important for the production of serotonin. Increasing tryptophan may help to normalize sleep patterns.

The polymer used for making missiles, solid propellant rocket motors and pressure vessels is

  1. Polystyrene

  2. Polyethylene

  3. Polypropylene

  4. Polyacrylonitrile


Correct Option: D
Explanation:

Polyacrylonitrile (PAN) is a resinous, fibrous, or rubbery organic polymer. PAN fibres are the chemical precursor of high-quality carbon fibre. It is chemically modified to make the carbon fibres found in plenty of both high-tech and common daily applications such as civil and military aircrafts,  primary and secondary structures, missiles, solid propellant rocket motors, pressure vessels, fishing rods, tennis rackets, badminton rackets and high-tech bicycles.

Which among the following can be excluded from the category of proteins?

  1. Enzymes

  2. Receptors

  3. Immunoglobulin or Antibodies

  4. None of these


Correct Option: D
Explanation:

All are proteins.

The amino acid strengthening the protective lining of the stomach and intestines is

  1. Creatine

  2. Cysteine

  3. GABA

  4. Glutamine


Correct Option: B
Explanation:

Cysteine strengthens the protective lining of the stomach and intestines, which may help prevent damage caused by aspirin and similar drugs.

Which among the following is a secondary diazo dye?

  1. Congo red

  2. Crystal violet

  3. Janus Green B

  4. Yellow 2G


Correct Option: A
Explanation:

Congo red is a secondary diazo dye. Congo red is water soluble, yielding a red colloidal solution; its solubility is better in organic solvents such as ethanol. It has a strong, though apparently non-covalent affinity to cellulose fibres.

The protein structure defining the protein molecule in 3d is

  1. Quaternary structure

  2. Ternary structure

  3. Secondary structure

  4. Primary structure


Correct Option: C
Explanation:

One of the main conformational parameter of the amino acid structure is the value of the PHI and PSI angles. These angles completely define the conformation of the polypeptide chain. With some special values for these angles the main chain can adopt specially classified conformations, like alpha-helix or beta-strand. The other main feature of the protein secondary structure is the local stabilisation by hydrogen bonds. These conformations are classified as a protein secondary structure.

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