How much gold and copper(in g), respectively, are required to make a 120 g bar of 22 carat gold?

• 90 and 30

• 100 and 20

• 110 and 10

• 120 and 0

A water tank that 40% empty holds 40L more water than when it is 40% full. How much water does it hold when it is full?

• 100L

• 75L

• 120L

• 200L

If all the angles of a triangle are prime numbers, which of the following could be one such angle?

• 89^°

• 79^°

• 59^°

• 29^°

The Cl^– content of red blood cells (RBCs) in the venous blood was found to be higher than that in arterial blood in a human subject. Following proposals were made to explain these observations:

(a)The high pCO₂ in venous plasma leads to increased diffusion of CO₂ into RBC and the formation of H₂CO₃.

(b) HCO₃ ^– content in the RBC of venous blood becomes much greater than that in plasma.

(c) The excess HCO₃ ^– leaves the RBC of venous blood along with Na+ to plasma by a Na⁺ – HCO₃ ^– symporter.

(d) The increased Na⁺ in the venous plasma is transported to the RBC along with Cl– Select the combination with INCORRECT statements from the following options. 

• (a) and (b)

• (b) and (c)

• (a) and (d) 

• (c) and (d)

Two Hfr strains, Hfr-1 (arg⁺ leu⁺ gal⁺ str^s) and Hfr-2 (arg⁺ his⁺ gal⁺ pur^r str^s) were mated with a F– strain (arg^– leu^– gal^– his^– pur^s str^r). The results of the interrupted mating experiment are shown as plots ‘a’ and ‘b’, respectively.

Based on these results, identify which of the options accurately reflects the order of loci? 

Which one of the following statements is true? 

• The specific rotation of enantiomers will be identical 

• The rate constant of a first order reaction has only time but no concentration units

• The value of pH + pOH depends on temperature 

• The bond disassociation energy (kJ/mol) of –C–C– will be greater than –C ≡C– 

Which one of the following statements on protein conformation is NOT true?

• Dihedral angles of side-chains in amino acids are depicted in the Ramachandran plot

• Infrared spectroscopy can be used to deduce hydrogen bonding in peptides

• Three dimensional structures of protein composed of ~100 amino acids can be obtained by nuclear magnetic resonance spectroscopy

• Globular proteins have α-helical and β-sheet components. 

Choose the correct answer from the following statements on biosynthesis

• In the biosynthesis of palmitate, all the carbon atoms are derived from activated malonate 

• The amino acids Met, Thr, Lys, Ile, Val and Leu are biosynthesized from oxaloacetate and pyruvate in most bacteria 

• Alanine is a major precursor for the biosynthesis of porphyrin

• Tryptophan is converted to L-DOPA in the biosynthesis of epinephrine 

Which one of the following statements on nucleic acids is NOT true? 

• The conformation of ribose in DNA is α-2'-deoxy-D-ribofuranose

• Hydrolysis of RNA takes place under alkaline conditions unlike DNA, as the 2'-hydroxyl in RNA acts as a nucleophile in an intramolecular displacement

• DNA can occur in different three-dimensional forms 

• In DNA, deamination of cytosine to uracil can occur in a non-enzymatic manner 

A rectangular photo frame of size 30cm× 40cm has a photograph mounted at the centre leaving a 5cm border all around. The area of the border is

• 600 cm²

• 350 cm²

• 400 cm²

• 700 cm²