A. Activation energy for enzyme catalysed hydrolysis of sucrose is lower than that of acid catalysed hydrolysis.
B. During denaturation, secondary and tertiary structures of a protein are destroyed but primary structure remains intact.
C. Nucleotides are joined together by glycosidic linkage between $\text{C}_1$ and $\text{C}_4$ carbons of the pentose sugar.
D. Quaternary structure of proteins represents overall folding of the polypeptide chain.
Choose the correct answer from the options given below :
Analysis of Statements
Statement A: Activation Energy Comparison
Enzymes act as biological catalysts. They significantly lower the activation energy required for a biochemical reaction compared to non-biological catalysts like acids. For the hydrolysis of sucrose, enzyme-catalyzed hydrolysis requires less activation energy than acid-catalyzed hydrolysis.
Conclusion: Statement A is correct.
Statement B: Protein Denaturation
Protein denaturation involves the disruption of the higher-order structures: the secondary structure (e.g., alpha-helices, beta-sheets) and the tertiary structure (the overall 3D folding of a single polypeptide chain). These structures are maintained by relatively weak bonds (hydrogen bonds, hydrophobic interactions, ionic bonds) and disulfide bridges. The primary structure, which is the sequence of amino acids linked by strong covalent peptide bonds, remains intact during denaturation.
Conclusion: Statement B is correct.
Statement C: Nucleotide Linkage
Nucleotides are the monomers of nucleic acids (DNA and RNA). They are linked together by phosphodiester bonds. These bonds form between the phosphate group attached to the 5' carbon of one pentose sugar and the hydroxyl group on the 3' carbon of the pentose sugar of the next nucleotide.
Glycosidic linkages are typically found connecting monosaccharides in polysaccharides or linking the nitrogenous base to the pentose sugar in a nucleotide.
Conclusion: Statement C is incorrect.
Statement D: Quaternary Structure
The quaternary structure of proteins refers to the arrangement and interaction of multiple polypeptide chains (subunits) that associate to form a functional protein complex. While the folding of a single polypeptide chain constitutes the tertiary structure, the quaternary structure describes how these already folded chains are assembled and oriented relative to each other.
Conclusion: Statement D is correct.
Final Answer Determination
Based on the analysis:
- Statement A is correct.
- Statement B is correct.
- Statement C is incorrect.
- Statement D is correct.
Therefore, the correct statements are A, B, and D.
The option including A, B, and D is Option 1.
Similar Questions
- In Dumas method for estimation of nitrogen, 0.50 g of an organic compound gave 70 mL of nitrogen collected at 300 K and 715 mm pressure. The percentage of nitrogen in the organic compound is ______ %.
(Aqueous tension at 300 K is 15 mm). Given below are two statements:
Statement I: The dipole moment of R-CN is greater than R-NC and R-NC can undergo hydrolysis under acidic medium to produce
Statement II: R-CN hydrolyses under acidic medium to produce a compound which on treatment with $\text{SOCl}_2$, followed by the addition of $\text{NH}_3$ gives another compound(x). This compound (x) on treatment with $\text{NaOCl/NaOH}$ gives a product, that on treatment with $\text{CHCl}_3\text{/KOH/}\Delta$ produces R-NC
In the light of the above statements, choose the correct answer from the options given below- Given below are two statements:
Statement I: Cross aldol condensation between two different aldehydes will always produce four different products.
Statement II: When semicarbazide reacts with a mixture of benzaldehyde and acetophenone under optimum pH, it forms a condensation product with acetophenone only.
In the light of the above statements, choose the correct answer from the options given below - $0.25 \text{ g}$ of an organic compound "A" containing carbon, hydrogen and oxygen was analysed using the combustion method. There was an increase in mass of $\text{CaCl}_2$ tube and potash tube at the end of the experiment. The amount was found to be $0.15 \text{ g}$ and $0.1837 \text{ g}$, respectively. The percentage of oxygen in compound A is ______ %. (Nearest integer)
(Given: molar mass in $\text{g mol}^{-1}$ $\text{H} : 1, \text{C} : 12, \text{O} : 16$) - Grignard reagent $\text{RMgBr (P)}$ reacts with water and forms a gas $\text{(Q)}$. One gram of Q occupies $1.4 \text{ dm}^3$ at STP. (P) on reaction with dry ice in dry ether followed by $\text{H}_3\text{O}^+$ forms a compound $\text{(Z)}$. 0.1 mole of $\text{(Z)}$ will weigh _________ g. (Nearest integer)
- Given below are four compounds :
(a) n-propyl choride
(b) iso-propyl chloride
(c) sec-butyl chloride
(d) neo-pentyl chloride
Percentage of carbon in the one which exhibits optical isomerism is : - By usual analysis, $1.00\text{ g}$ of compound (X) gave $1.79\text{ g}$ of magnesium pyrophosphate. The percentage of phosphorus in compound (X) is : __________ (nearest integer)
(Given, molar mass in $\text{g\ mol}^{-1}$ : $\text{O} = 16, \text{Mg} = 24, \text{P} = 31$) - The correct order of the rate of the reaction for the following reaction with respect to nucleophiles is :
$\text{CH}_3\text{Br} + \text{Nu}^\ominus \longrightarrow \text{CH}_3\text{Nu} + \text{Br}^\ominus$ Given below are two statements :
Statement I : Compound (X), shown below, dissolves in $\text{NaHCO}_3$ solution and has two chiral carbon atoms
Statement II : Compound (Y), shown below, has two carbons with $\text{sp}^3$ hybridization, one carbon with $\text{sp}^2$ and one carbon with $\text{sp}$ hybridization
In the light of the above statements, choose the correct answer from the options given below :
Consider the above sequence of reactions. The number of bromine atom(s) in the final product (P) will be :
Important Questions from Organic Chemistry
- In Dumas method for estimation of nitrogen, 0.50 g of an organic compound gave 70 mL of nitrogen collected at 300 K and 715 mm pressure. The percentage of nitrogen in the organic compound is ______ %.
(Aqueous tension at 300 K is 15 mm). Given below are two statements:
Statement I: The dipole moment of R-CN is greater than R-NC and R-NC can undergo hydrolysis under acidic medium to produce
Statement II: R-CN hydrolyses under acidic medium to produce a compound which on treatment with $\text{SOCl}_2$, followed by the addition of $\text{NH}_3$ gives another compound(x). This compound (x) on treatment with $\text{NaOCl/NaOH}$ gives a product, that on treatment with $\text{CHCl}_3\text{/KOH/}\Delta$ produces R-NC
In the light of the above statements, choose the correct answer from the options given below- Given below are two statements:
Statement I: Cross aldol condensation between two different aldehydes will always produce four different products.
Statement II: When semicarbazide reacts with a mixture of benzaldehyde and acetophenone under optimum pH, it forms a condensation product with acetophenone only.
In the light of the above statements, choose the correct answer from the options given below - $0.25 \text{ g}$ of an organic compound "A" containing carbon, hydrogen and oxygen was analysed using the combustion method. There was an increase in mass of $\text{CaCl}_2$ tube and potash tube at the end of the experiment. The amount was found to be $0.15 \text{ g}$ and $0.1837 \text{ g}$, respectively. The percentage of oxygen in compound A is ______ %. (Nearest integer)
(Given: molar mass in $\text{g mol}^{-1}$ $\text{H} : 1, \text{C} : 12, \text{O} : 16$) - Grignard reagent $\text{RMgBr (P)}$ reacts with water and forms a gas $\text{(Q)}$. One gram of Q occupies $1.4 \text{ dm}^3$ at STP. (P) on reaction with dry ice in dry ether followed by $\text{H}_3\text{O}^+$ forms a compound $\text{(Z)}$. 0.1 mole of $\text{(Z)}$ will weigh _________ g. (Nearest integer)
