Tropic hormones or tropins are secreted by
Which one of the following is necessary for evolution to be driven by genetic drift?
Biotin deficiency can arise due to consumption of diet rich in
In a plant species, yellow seed colour (Y) is completely dominant over white (y). A genetic cross between plants with yellow seeds and plants with white seeds yielded a progeny population of 48 yellow-seeded and 52 white-seeded plants. The genotypes of the yellow-seeded and the white-seeded parent plants, respectively, are most likely to be
Thomas Cech discovered RNA self-splicing in
The core glycan moiety of N-linked glycoproteins contains
Organophosphate pesticides kill insects by inhibiting
Which one of the following conditions leads to an approximately 50-fold increase in RNA transcription of the lac operon? (CRP stands for cyclic AMP [cAMP] receptor protein)
P: Binding of CRP-cAMP complex to a site near the lac promoter
Q: Binding of CRP-cAMP complex to a site near the lac operator
R: Lac repressor bound to the lac operator
S: Lac repressor not bound to the lac operator
Which one of the following photosynthetic organisms does not release oxygen as a by-product of the light reaction?
In plant systematics, which one of the following species belongs to the branch at the very base of the angiosperm phylogenetic tree?
The molecular weight (Da) of the zwitterionic form of the peptide GAGAGAGA is closest to
If y = x2, then dx/dy is
Which one of the following plots represents exponential growth?
Naive T lymphocytes can be stimulated by the activated dendritic cells that bear
In rearrangement of immunoglobulin heavy chain, N-nucleotides
Which one of the following matches is CORRECT between the microorganisms given in Group A with their requirement of oxygen in Group B?
Which one of the following is TRUE for the function = x2 + 1?
Match the metabolic pathways in Group A with corresponding enzymes in Group B
Which one of the following statements is INCORRECT for competitive inhibition in an enzyme catalysed reaction?
In a human cell, β-oxidation of a saturated fatty acyl CoA molecule produced 8 acetyl CoA, 7 H2O and 28 ATP. The oxidised fatty acyl CoA is
Match the diseases in Group A with their corresponding causative microorganisms in Group B
In an experiment to examine the role of exopolymeric substances (EPS) on bacterial growth, a wildtype strain (S+) and a mutant strain deficient in EPS production (S−) were grown in monocultures as well as in co-culture (in equal proportion of S+and S−). The CFU (colony forming units) of these cultures measured after 24 hours are shown in the following figure.
Q. Which one of the following phenomena best describes the interaction between the wild-type strain (S+ ) and mutant strain (S−)?
If a fossil that has been discovered recently contains 0.2% of the that was present when the fossil was formed, then the age of the fossil in years is likely to fall in the range of
A photosynthetic algal filament is illuminated with white light that has passed through a prism such that the left and the right ends of the filament receive violet and red lights, respectively. The amount of oxygen released by this filament will be
Which one of the following statements is TRUE for dynein and kinesin family of motor proteins?
Which one of the following statements is TRUE about flagella?
Caffeine is a plant-based drug that
2,4-Dinitrophenol (DNP) is an uncoupler that
Which one of the following statements is INCORRECT about the prokaryotic and eukaryotic organisms on the Earth?
Which is the CORRECT chronological order, from the least recent to the most recent, of the four evolutionary events listed below?
P. Earliest evidence of terrestrial arthropods
Q. Appearance of Ediacaran fauna
R. Extinction of the large, non-flying dinosaurs
S. Origin of mammals
Which of the following changes would cause a shift in the membrane potential of a neuronal cell from –70 mV to –50 mV?
In this system of two reactions, A → 2B and B → 2C , which of the following statements is/are TRUE at steady-state?
The function f(x) = x2 − 6x + 8 is positive when
A typical α-helix in a native polypeptide chain has
Insulin action on a target cell causes an increase in
Which of the following statements is/are TRUE for the function f(x) shown in the figure given below?
Which of the following coenzymes is/are present in the pyruvate dehydrogenase complex?
Which of the following disorders in humans is/are due to a defect/deficiency in enzymes involved in the urea cycle?
Ricin, a protein from castor beans, causes toxicity in humans by
During photosynthesis in higher plants, oxygen is produced
The function f(x) = sin(x) e−x is equal to zero in the range 0 < x < 2π for x =____ radians (round off to 2 decimal places)
A spherical bacterium has a diameter of 2 µm. Its volume to surface area ratio is equal to ____ µm (round off to 2 decimal places)
The value of the integral is equal to ____ (round off to 2 decimal places)
The velocity of an enzyme-catalysed reaction following Michaelis–Menten kinetics, at the substrate concentration equal to 0.3×Km, is equal to ____ × Vmax (round off to 2 decimal places)
The angle (in degrees) between the hour hand and the minute hand of a 12-hour clock showing 6:30 is ___ (round off to 1 decimal place)
Values of (standard Gibbs free energy of formation) for molecules A, B, and C are –34 kJ/mol, 84 kJ/mol and –100 kJ/mol, respectively. The for the reaction + → would be ____ kJ/mol (round off to 1 decimal place)
A bacterial population in the log-phase grows from 4 × 106 cells to 8.64 × 106 cells in 20 minutes. The doubling time of the bacterium is ____ minutes (round off to 1 decimal place)
Tryptophan (Trp) is encoded by UGG, phenylalanine (Phe) is encoded by UUU and UUC, isoleucine (Ile) is encoded by AUU, AUC and AUA, and glycine (Gly) is encoded by GGU, GGC, GGA and GGG. The maximum number of RNA segments with unique sequences that can encode the polypeptide Ile-Phe-Trp-Ile-Gly-Trp would be ____
In an examination consisting of 100 multiple choice questions, each question has four choices out of which only one is correct. A student scores +1 for each correct answer and a negative mark of 1/5 for each wrong answer. The correct choices are uniformly distributed across the four choices. If an unprepared student always selects the first choice for each question, then the expected value of the student’s total score in the examination would be ____ (round off to 1 decimal place)
In a large insect population, males and females are equally abundant. If a student collects four insects from this population at random, the probability that all of them are male is ____ (round off to 2 decimal places)
An E. coli cell with an internal volume of 2 femtolitres contains 10 molecules of a repressor protein in its cytosol. The concentration of the repressor protein is ____ nM (round off to 1 decimal place)
The growth rate of a bacterial culture is given by where x is the density of the culture. The growth rate is maximum when the density is equal to ____ (round off to 1 decimal place)
A hypothetical plant forms 10 leaves, each of which is perfectly circular with 10 cm diameter. If the total number of stomata made by all these leaves is 7.85 × 106, then the stomatal density in these leaves would be ____ / mm2 (round off to 1 decimal place)
In a diploid population at Hardy–Weinberg equilibrium, the locus A has two alleles A1 and A2. If the frequency of A1A1 genotype is 0.01, then the frequency of the allele A2 is ____ (round off to 2 decimal places)
In the following figure, the radius of the circle circumscribing the regular hexagon is 2 cm. The area of the shaded region is ____ cm2 (round off to 2 decimal places)
The complete oxidation of one mole of palmitoyl CoA yields 23 moles of water and 16 moles of carbon dioxide. The amount of water that can be produced from 1 kg of tripalmitate is ____ mL (round off to 2 decimal places)
If x, y, and z are all positive and x + y + z = 9, the maximum value of xyz is ____
In the second-order reaction 2A → B, the initial concentration of A is 1.0 M and after 30 minutes, the concentration of A is 0.5 M. The rate constant of the reaction is ____ L/mol/h (round off to 2 decimal places)
Water from a full cylindrical vessel of height h and of unknown diameter is completely emptied to precisely fill two cylindrical vessels of the same diameter d and heights h and 3h. The diameter of the original vessel is ____ × d (round off to 2 decimal places)