JEE Chemistry Biomolecules MCQs Set C

Question: Which is a fat soluble vitamin?

• a) Vitamin A
• b) Vitamin C
• c) Vitamin B₆
• d) Vitamin B₂

Answer: Vitamin A

Question: Vitamin B₂, a water soluble vitamin is also known as

• a) riboflavin
• b) pyridoxine
• c) thiamine
• d) ascorbic acid

Answer: riboflavin

Question: Which of the following statements about vitamin B₁₂ isincorrect ?

• a) It is also present in rain water
• b) It is needed for human body in very small amounts
• c) It also occurs in plants
• d) It has a cobalt atom

Answer: It is also present in rain water

Question: The couplings between base units of DNA is through

• a) Hydrogen bonding
• b) Covalent bonding
• c) Electrostatic bonding
• d) van der Waals forces

Answer: Hydrogen bonding

Question: Which of the following is correct about H-bonding in nucleotide?

• a) A --- T and G --- C
• b) G --- T and A --- C
• c) A --- A and T --- T
• d) A --- G and T --- C

Answer: A --- T and G --- C

Question: In DNA, the complimentary bases are:

• a) Adenine and thymine; guanine and cytosine
• b) Adenine and thymine ; guanine and uracil
• c) Adenine and guanine; thymine and cytosine
• d) Uracil and adenine; cytosine and guanine

Answer: Adenine and thymine; guanine and cytosine

Question: The segment of DNA which acts as the instrumental manual for the synthesis of the protein is

• a) gene
• b) nucleotide
• c) ribose
• d) nucleoside

Answer: gene

Question: In DNA the linkages between different nitrogenous bases are

• a) H-bonding
• b) peptide linkage
• c) phosphate linkage
• d) glycosidic linkage

Answer: H-bonding

Question: DNA multiplication is called as

• a) replication
• b) transduction
• c) translation
• d) transcription

Answer: replication

Question: Chromosomes are made from

• a) proteins and nucleic acids
• b) carbohydrates and nucleic acids
• c) nucleic acids
• d) proteins

Answer: proteins and nucleic acids

Question: The double helical structure of DNA was proposed by

• a) Watson and Crick
• b) Meichers
• c) Khorana
• d) Emil Fischer

Answer: Watson and Crick

Question:

• a) DNA
• b) lipid
• c) RNA
• d) carbohydrates

Answer: DNA

 More Questions.............................................

Question: Which of the following compounds is responsible for the transmission of heredity characters?

• a) DNA
• b) Haemoglobin
• c) Glucose
• d) RNA

Answer: DNA

Question: The latest discovery in cytology is that of

• a) genetic code
• b) None of these
• c) respiration
• d) enzyme

Answer: genetic code

Question: Energy is stored in our body in the form of

• a) ATP
• b) fats
• c) ADP
• d) carbohydrates

Answer: ATP

Question: The chemical change in DNA molecule that could lead to synthesis of protein with an altered amino acid sequence is called

• a) mutation
• b) lipid formation
• c) replication
• d) cellular membrane

Answer: mutation

Question:  DNA has deoxyribose, a base and the third component which is

• a) phosphoric acid
• b) adenine
• c) ribose
• d) thymine

Answer: phosphoric acid

Question: The process by which synthesis of protein takes place based on the genetic information present in m-RNA is called

• a) Translation
• b) Replication
• c) Transcription
• d) Messenger hypothesis

Answer: Translation

Question:  Which of the following structures represents thymine ?

• a)

  

• b)

  

• c)

  

• d) None of these

Answer:

Question: When adenine is attached to ribose sugar, it is called adenosine. To make a nucleotide from it, it would require

• a) addition of phosphate
• b) oxygenation
• c) addition of a base
• d) hydrogenation

Answer: addition of phosphate

Question: Which of the following is not present in a nucleotide?

• a) Tyrosine
• b) Cytosine
• c) Guanine
• d) Adenine

Answer: Tyrosine

Question: The function of DNA in an organism is

• a) All of these
• b) to assist in the synthesis of proteins and polypeptides
• c) to store information of heredity characteristics
• d) to assist in the synthesis of RNA molecule

Answer: All of these

Question: Which of the following statements regarding DNA fingerprinting is incorrect?

• a) It is different for every cell and cannot be altered by any known treatment
• b) It is used to determine paternity of an individual
• c) It cannot be altered by surgery
• d) It is used in forensic laboratories for identification of criminals

Answer: It is different for every cell and cannot be altered by any known treatment

Question: Read the following statements and choose the correct answer?

(i) All monosaccharides are reducing sugars.
(ii) All monosaccharides are not reducing sugars.
(iii) In disaccharides if aldehydic or ketonic groups are bonded, these are non– reducing sugars.
(iv) In disaccharides if aldehydic or ketonic groups are free, these are reducing sugars.

• a) (i), (iii) and (iv)
• b) (i) and (iv)
• c) (ii), (iii) and (iv)
• d) (ii) and (iv)

Answer: (i), (iii) and (iv)

Question: Which of the following statement(s) is/are correct?

(i) Glucose is reducing sugar
(ii) Sucrose is reducing sugar
(iii) Maltose is non reducing sugar
(iv) Lactose is reducing sugar

• a) (i) and (iv) only
• b) (i) and (ii) only
• c) (i) and (iii) only
• d) All of these

Answer: (i) and (iv) only

Question:  Which of the following statements regarding carbohydrates are correct?

(i) Lactose is the carbohydrate found in milk.
(ii) More than 25 monosaccharides occur naturally.
(iii) Sucrose on hydrolysis gives one molecule each of glucose and fructose.
(iv) Maltose is a non-reducing sugar whereas sucrose is a reducing disaccharide sugar.

• a) (i) and (iii)
• b) (iii) and (iv)
• c) (i), (ii) and (iii)
• d) (ii), (iii) and (iv)

Answer: (i) and (iii)

Question:  Read the following statements.

(i) Pyran is a cyclic organic compound with one oxygen atom and five carbon atom.
(ii) The cyclic structure of glucose is correctly represented by Haworth strucure.
(iii) Five membered cyclic structure of glucose is called pyranose structure.
Which of the following statement(s) is/are true?

• a) (i) and (ii)
• b) (i), (ii) and (iii)
• c) (i) and (iii)
• d) Only (iii)

Answer: (i) and (ii)

Question: Consider the following statements.

(i) Linkage between two monosaccharide units through oxygen atom is called glycosidic linkage.

(ii) Sucrose on hydrolysis gives an equimolar mixture of fructose and glucose which is dextrorotatory.

(iii) Lactose consists of linkage between C₁ of galactose and C₄ of glucose.

(iv) Out of two components of starch the component present in greater proportion is insoluble in water.

(v) Glycogen is also known as animal starch because it is structurally similar to amylose a component of starch.

Which of the following is the correct code for statements above?

• a) TFTTF
• b) FTTTF
• c) FFFTT
• d) TFTFT

Answer: TFTTF

Question:

• a) (i) and (ii)
• b) (i) (iii) and (iv)
• c) (i), (ii) and (iii)
• d) (iii) and (iv)

Answer: (i) and (ii)

Question: Which among the following statements are true for glycine?

(i) It exists in crystalline form
(ii) It is optically active
(iii) It is soluble in water
(iv) It can form Zwitter ions

• a) (i), (iii) and (iv)
• b) (i), (ii) and (iii)
• c) (i), (ii) and (iv)
• d) (ii), (iii) and (iv)

Answer: (i), (iii) and (iv)

Question:

• a) (i) and (iii)
• b) (iii) and (iv)
• c) (i), (ii) and (iv)
• d) (ii), (iii) and (iv)

Answer: (i) and (iii)

Question: Which of the statements about "Denaturation" given below are correct ?

(i) Denaturation of proteins causes loss of secondary and tertiary structures of the protein.
(ii) Denaturation leads to the conversion of double strand of DNA into single strand
(iii) Denaturation affects primary strucrture which gets distorted.

• a) (i) and (ii)
• b) (ii) and (iii)
• c) (i) and (iii)
• d) (i), (ii) and (iii)

Answer: (i) and (ii)

Question: Which Of the following statements about enzymes which ones are true?

(i) Enzymes lack in nucleophilic groups
(ii) Enzymes are highly specific both in binding chiral substrates and in catalysing their reactions
(iii) Enzymes catalyse chemical reactions by lowering the energy of activation
(iv) Pepsin is a proteolytic enzyme.

• a) (ii), (iii) and (iv)
• b) (i) and (iv)
• c) (i) and (iii)
• d) (i)

Answer: (ii), (iii) and (iv)

Question: Which of the following statements are correct ?

(i) Vitamins A, D, E and K are insoluble in water.
(ii) Vitamins A, D, E and K are stored in liver and adipose tissues.
(iii) Vitamin B and vitamin C are water soluble.
(iv) Water soluble vitamins should not be supplied regularly in diet.

• a) (i), (ii) and (iii)
• b) (ii) and (iv)
• c) (i), (ii) and (iv)
• d) (i) and (iv)

Answer: (i), (ii) and (iii)

Question: Which of the following statement(s) is/are correct?

(i) Information regarding the sequence of nucleotides in the chain of a nucleic acid is called its primary structure.
(ii) In secondary structure of DNA adenine forms hydrogen bonds with guanine whereas cytosine forms hydrogen bonds with thymine.
(iii) RNA molecules are of three types m-RNA, r-RNA and t-RNA and they all perform different functions.

• a) (i) and (iii)
• b) (iii) only
• c) (ii) only
• d) (ii) and (iii)

Answer: (i) and (iii)

Question:

• a) TFTF
• b) FTFF
• c) FFTT
• d) TFFT

Answer: TFTF

Question:

• a) A – (s), B – (r), C – (t), D – (p), E – (q)
• b) A – (r), B – (q), C – (s), D – (p), E – (t)
• c) A – (q), B – (p), C – (r), D – (s), E – (t)
• d) A – (s), B – (p), C – (t), D – (q), E – (r)

Answer: A – (s), B – (r), C – (t), D – (p), E – (q)

Question:

• a) A – (r), B – (p,s), C – (p), D – (p, q)
• b) A – (p,q), B – (p,s), C – (p), D – (r)
• c) A – (p,s), B – (r), C – (p), D – (p,q)
• d) A – (r), B – (p,s), C – (p,q), D – (p)

Answer: A – (r), B – (p,s), C – (p), D – (p, q)

Question:

• a) A – (s), B – (t), C – (p), D – (r), E – (q)
• b) A – (t), B – (s), C – (p), D – (r), E – (q)
• c) A – (s), B – (t), C – (p), D – (q), E – (r)
• d) A – (t), B – (s), C – (p), D – (r), E – (r)

Answer: A – (s), B – (t), C – (p), D – (r), E – (q)

Question: Glycosidic linkage is actually an

• a) Ether bond
• b) Amide bond
• c) Carbonyl bond
• d) Ester bond

Answer: Ether bond