Many organisms use cilia to move inside fluids. Which of the following statements is true for ciliary motion? The viscous friction coefficient for the motion of a cilium parallel to its axis is smaller than the viscous friction coefficient for the motion of a cilium perpendicular to its axis. The viscous friction coefficient for the motion of a cilium parallel to its axis is equal to the viscous friction coefficient for the motion of a cilium perpendicular to its axis. The viscous friction coefficient for the motion of a cilium parallel to its axis is larger than the viscous friction coefficient for the motion of a cilium perpendicular to its axis. The viscous friction coefficient for the motion of a cilium parallel to its axis tends to infinity when compared with the viscous friction coefficient for the motion of a cilium perpendicular to its axis.

Ciliary Motion and Viscous Friction

There are three genes a, b, and c. Percentage of crossing over between a and b is 20%, b and c is 28% and a and c is 8%. What is the order of arrangement of these three genes on the chromosome? a, b, c a, c, b b, a, c c, b, a

Determining Gene Order from Crossing Over Percentages

E. coli was engineered to express two different fluorescent proteins (GFP and RFP) under identical promoters. The strain is engineered such that the two proteins are expressed at a 1:1 ratio, giving the bacteria a ‘yellow’ colour. As the culture grows further over time, which of the following scenarios is most likely? Assuming that neither GFP nor RFP confers any kind of selection pressure. GFP starts predominating over RFP, turning the cultures green RFP starts predominating over GFP, turning the culture red Individual bacterium in the culture starts expressing the two proteins distinctly, providing a mosaic pattern Robust regulatory mechanisms for transcription and translation ensure the maintenance of 1:1 ratio, thus the culture will remain ‘yellow’.

Stochastic Gene Expression in E. coli

Co-operation, including seemingly altruistic behaviours can be advantageous when there is Reciprocity. This theory of reciprocal altruism provides one explanation for cases of seemingly altruistic behaviour by various animals (for example, sharing of blood meal in vampire bats). Under which of the following conditions this theory cannot be used as an explanation of co-operative behaviour? The animal is an invertebrate The animal is distributed such that repeated encounter between conspecifics is very rare The animal cannot recognize kins from non-kins The animal can recognize non-kins, but cannot distinguish between close and distant distant genetic relatives

Reciprocal Altruism in Animals

Over time, cracks and damage occur in concrete. One way to repair this is by introducing microbes into concrete during the building process. These would heal the concrete if cracks appear. Which type of microbial species have been found suitable in self-healing concrete. Aspergillus sp. Bacillus sp. Methanococcus sp. Dictyostelium sp.

Self‑Healing Concrete with Bacillus Bacteria

Acorn worms have been extensively studied as a way to understand the evolution of the chordates. Which of the following features is a distinct chordate affinity found in acorn worms. presence of post-anal tail radially symmetrical body plan presence of pharyngeal gill slits ventral hollow nerve cord

Chordate Affinities of Acorn Worms

Species that live on mountain tops are more prone to extinction due to climatic warming. This is because: They are all long-lived, and adapting to these changes in climate is not possible. Mountain tops have small areas, and species cannot shift their distributions upwards. Mountains are eroding over time and mountaintops are physically unstable. Mountain tops have low oxygen and adapting to both increased temperature and low oxygen is not possible.

Why Mountain Top Species Are More Prone to Extinction Due to Climate Warming

On an expedition to Mars, the newest rovers discover microbial life. Yay! On further probing, scientists discover that Martian microbes also use DNA, RNA, and proteins. Researchers changed one nucleotide in a Martian gene and found that the resultant mutant protein had changes in 3 adjacent amino acids. These observations are consistent with a Martian genetic code consisting of: Non-overlapping 2 codons Overlapping 2 base codons Overlapping triplet codons Overlapping 4 base codons

Martian Genetic Code

An altered form of a replicative DNA polymerase lacks 3’→ 5’ exonuclease activity. This alteration would most likely result in which of the following? A decrease in processivity An increased mutation rate An inability to replicate DNA An inability to remove RNA primers

Loss of 3’→5’ Exonuclease Activity in Replicative DNA Polymerase

Which of the following phyla are considered diploblastic (i.e. consisting of two germ layers)? Echinodermata Chordata Mollusca Cnidaria

Diploblastic Animals: Why Cnidaria (Not Echinodermata, Chordata or Mollusca)

Mature vertebrate erythrocytes always: Lack a nucleus Have a bi-concave shape Use haemoglobin to carry oxygen All of the above

Mature Vertebrate Erythrocytes

While culturing a eukaryotic cell line, you add radio-labelled methionine in the culture media. After addition, you are able to cleanly separate individual organelles at different times. In which organelle would you detect radioactivity first? Rough Endoplasmic Reticulum Lysosome Mitochondria Nucleus

First Organelle to Show Radioactivity After Adding Radiolabelled Methionine

The nervous systems of invertebrates differ from the nervous systems of vertebrates in the following way: Invertebrate neurons lack a myelin sheath around their axons. Invertebrate neurons do not generate action potentials Invertebrate neurons lack electrical synapses All of the above

Invertebrate Neurons Lack Myelin Sheath

A mitochondrial mutation is detected in a man. This mutation is only lethal beyond the age of 70. He marries a woman who does not carry the mutation, and they then have children. What percentage of his grand-daughters would be carriers for this mutation 100% 0% 25% 33%

Mitochondrial Mutation Inheritance

If a person has memory loss which part of the brain is most likely affected? Amygdala Spinal cord Neocortex Hippocampus

Which Part of the Brain Is Affected in Memory Loss?

Which of the following molecules is a tautomer of the structure shown?

Tautomerism in Pyrimidine Ring

A series of alkanes is shown below. Which one has the lowest melting point 2 3 1 4

Lowest Melting Point in a Series of Cycloalkanes

The data in the table in the table below is collected for an enzyme-catalyzed reaction. The Km for this enzyme is approximately: 8 x 10-6 mM 2.0 x 10-5 mM 8.0 x 10-5 mM 2 x 10-2 mM

Km calculation from enzyme‑catalyzed reaction data table

Which of the following options show the appropriate solubility (S) curve of globular protein in polar solvent when plotted as a function of pH. IEP is the isoelectric point of the protein.

Protein Solubility Curve vs pH

Identify the statement about haemoglobin that is not correct Oxygen binds the porphyrin ligands of the haem groups Oxygen binding is sensitive to pH Carbon Monoxide is toxic as it binds haemoglobin with a higher affinity than oxygen Oxygen binding to Haemoglobin is reversible.

Hemoglobin and Oxygen Binding

What chemical would you add to D2O to produce ND3 TiN NO2 Li3N NaNO2

Chemical to Add to D₂O for ND₃ Production

You have added a drop of high concentration sugar solution in a bowl of water at room temperature. A few minutes later, which of the following statements is true? Sugar solution has high viscosity. Hence, the rate of change of concentration of the sugar solution will be zero. The rate of change of concentration of the sugar solution at a point in space is proportional to the second derivative of concentration with time The molar flux of sugar molecules is proportional to the concentration gradient The temperature gradient will be proportional to the second derivative concentration with time

Diffusion of Sugar in Water

Choose the most appropriate option from below for the spectroscopic evidence of hydrogen bond formation. D—H……A where D and A are the hydrogen bond donor and acceptor respectively. H is the hydrogen atom. Red-shift in the D—H vibrational frequency and de-shielding of H in D—H is observed in IR and NMR spectrum respectively. Blue-shift in the D—H vibrational frequency and de-shielding of H in D—H is observed in IR and NMR spectrum respectively. Blue-shift in the D—H vibrational frequency and shielding of H in D—H is observed in IR and NMR spectrum respectively. Red-shift in the D—H vibrational frequency and shielding of H in D—H is observed in IR and NMR spectrum respectively.

Spectroscopic Evidence of Hydrogen Bond Formation

Silicates, Silicone and silica all share the follow: A linear chair structure Si-O bonds Si-Si bonds Catalysis for hydrogenation

Common Features of Silicates, Silicone and Silica

Which one of the following statements is wrong? Cellulose is a polysaccharide Uracil is a pyrimidine Serine is a sulphur containing amino acid Sucrose is a disaccharide

Wrong Statement in Biomolecules

What does Kcat/Km signify? Specificity of enzyme for different substrates Rate of product formation Rate of substrate consumption Maximum rate of reaction

What Does Kcat/Km Signify in Enzyme Kinetics?

What does Kcat/Km signify? Specificity of enzyme for different substrates Rate of product formation Rate of substrate consumption Maximum rate of reaction

What Does Kcat/Km Signify in Enzyme Kinetics?

When large globular proteins are homogeneously mixed with short polymer chains, which of the following statements is true? Depletion interaction will keep the mixture homogeneous the smaller polymers will keep the larger proteins separated to maximize the protein entropy the smaller polymers will bind to the larger proteins the smaller polymers can push the larger proteins together to maximize their own entropy

Depletion Interaction in Protein–Polymer Mixtures

The rate of reaction for a second order reaction can be dependent on concentration of one reactant dependent on concentration of two reactants independent of product concentration all of the above

Second Order Reaction Rate

The roasting of cocoa beans or the baking of bread, gives us the flavours and aromas that we savour in these foods. It also produces melanoidins that give the brown colour associated with roasting or baking. Which chemical reaction is responsible for this delicious outcome? Diels-Alder reaction Wittig’s reaction Maillard reaction Perkin’s reaction

Maillard Reaction: The Chemical Magic Behind Roasted Cocoa Beans and Baked Bread Flavor

What is the molarity of water if its density is 1000kg/m3 (Molar mass of water is 18 g/mol) 55.55 moles 45.46 moles 60.0 moles 40.56 moles

Molarity of Water

The first 4 harmonics produced by an organ pipe open at both ends are 50Hz, 100Hz, 150Hz and 200Hz. Which of the harmonics will remain once one end of the pipe is closed? 50Hz and 150Hz only 100Hz and 200Hz only 150Hz and 200Hz only None

Open vs Closed End Frequencies

A particle is performing Brownian motion with a diffusion constant D, and has a half-life of τ. The root mean square distance it will be displaced from its starting position before decaying will scale as: Dτ D/τ

Brownian Motion RMS Displacement for a Decaying Particle

Both ends of an actin fibre of length L are pinned to two parallel surfaces, as shown below. The elasticity modulus is E, and the moment of inertia is I. A load P is applied as shown. What is the maximum load that this fiber can withstand without buckling?

Critical Buckling Load of an Actin Fibre with Pinned Ends

If the energy and momentum of a ball are E and P, respectively, its velocity will scale as: E/P P/E

Velocity Relation When Energy and Momentum of a Ball Are Given

Our skin is easy to pinch, but very hard to pull apart. Based on this property, which of these curves most likely represents the mechanical properties of skin? A B C B and C

Stress–Strain Curve of Skin

100 photons, one after the other, are sent to a photon detector that has a quantum efficiency of 0.1. How many times will the detector detect photons? exactly 10 times an average of 10 times with a root-mean-square deviation of 3 an average of 10 times with a root-mean-square deviation of 1 an average of 10 times with a root-mean-square deviation of 0.1

Photon Detector Quantum Efficiency

What happens to the protons in a given sample when an external magnetic field is applied? All protons align with the field All protons align opposite to the field All protons assume a random orientation Some protons align with the field and some align opposite to it

Proton Alignment in External Magnetic Field

If the ionisation energy of a hydrogen atom is E. When the electron in a hydrogen atom jumps from the first excited state to the ground state, the energy emitted is: E < E > E 0

Hydrogen Atom Ionization Energy

The returning motion of the boomerang is primarily driven by Aerodynamic forces acting on the two arms of the boomerang Due to central forces acting on the boomerang A combination of aerodynamic forces on the two arms and gyroscopic precession Adverse winds that blow back the boomerang towards the thrower

Boomerang Returning Motion

A solid cylindrical glass rod has length 20.0 ± 0.1 cm and diameter 5.00 ± 0.01 mm. What is the percentage uncertainty in the calculated volume of this rod? 0.1% 0.2% 0.7% 0.9%

Percentage Uncertainty in Cylinder Volume

How are chemical elements greater than atomic mass of iron are thought to be formed? In the core of stars In the core of earth By neutron star merger During the big bang

How Chemical Elements Heavier Than Iron’s Atomic Mass Are Formed

Electrons can be scattered from the surface of a metal to form a diffraction pattern. This shows that: Electrons can behave like waves Electrons have charge Electrons can behave like waves and particles Electrons can behave like particles

Electron Diffraction: Proving Electrons Behave Like Waves and Particles

A particle of mass m and initial velocity V is faced with a damping force proportional to the square of its velocity and equal to a v2. In how much time will the particle come to a stop? 2m/aV 2 ma/V 2 mV/a Never stop

Particle Damping Force v²

Electromagnetic radiation that is emitted from a nucleus is in the form of: Cherenkov radiation Gamma rays Ultraviolet light Microwaves

Electromagnetic Radiation Emitted from Nucleus

Heat and water loss in animals is proportional to the ratio of their surface area to volume. Imagine a spherical cow. When the radius of the cow doubles, its surface area-to-volume ratio: Reduces by 3/r Remains unchanged. Becomes half. Doubles

Surface Area to Volume Ratio in Spherical Cow

Imagine that you are looking at one cancer cell under the microscope, and trying to estimate the probability that it will die due to a chemotherapy regime. You know that 95% of cells treated with the chemotherapy turn on the P53 gene and that these cells have 80% chance of dying. The remaining 5% do not turn on P53 and have only 10% chance of dying. What is the probability that the cell you're looking at will die? 76.5% 66.5% 86.5% 69.75%

Cancer Cell Death Probability

A mammalian cell typically has 1.2 meters (when completely outstretched) of double stranded DNA. The total time to duplicate the DNA is 5 hours. How many origins of replication are there if the rate of duplication is 16µmeters/min? 2500 25 250 500

Mammalian Cell DNA Replication

If a healthy individual has a probability of 0.5 to contract COVID when s/he comes in contact with 1 COVID-positive individual, then what is the probability that the healthy individual has contracted COVID after coming in contact with 4 COVID-positive individuals? 2 1 0.0625 0.9375

Probability Healthy Individual Contracts COVID After 4 Positive Contacts

Identify the odd one out Nipah Covid-19 Small Pox Rabies

Identify the Eradicated Disease

Bacterial cell membrane is composed of an almost equal amount of protein and lipids. Assuming a bacterial cell as a sphere of diameter 2 micrometer, approximately how many lipids molecules will be there in that bacterial cell membrane. Assume, the surface area per lipid headgroup is 0.2 nm2 3×10^7 3×10^6 3×10^5 3×10^4

Bacterial Cell Membrane

A hypothesis is a statement that is: A best guess about a particular process Provable using experiments Testable using experiments Can neither be proved or disproved

Hypothesis in Science

Many of the world's deserts occur in two bands centred at around 30˚N and 30˚S latitude. This can be explained by Patterns of continental drift Patterns of atmospheric circulation above and below the equator Global climate changes that have occurred Latitudinal variation in soil types

Why Deserts Form at 30°N and 30°S

If only two nucleotides A and G occur in a 4-base pair DNA sequence, how many such sequences are possible? 4 8 16 32

How Many 4-Base Pair DNA Sequences Possible

For a normal distribution, if the mean is doubled, how does the area under the curve change? Doubles Halves Need standard deviation to estimate area Remains same

Normal Distribution Area Under Curve

You and your pet pigeon drive 24km due east and then 32km due north to a clearing in a forest. You release the pigeon so that it can fly home. If the pigeon flies at an approximate speed of 40km/h, and you average 50km/h on the drive home, who gets home first? You arrive first, by about 30 minutes You arrive first, by about 12 minutes Both you and the pigeon arrive at the same time You arrive last

Pigeon vs Driver Race

The maximum value of the function f(x) = 1 – ex in the range - infinite 2 1 0

Maximum Value of the Function

A family has three children. What is the probability that they have exactly one daughter? 1/8 3/8 1/4 3/4

Probability Family Three Children Exactly One Daughter

An axiom is A neuronal cell type a statement or proposition that summarises a principle a statement or proposition that can be proved to be true a statement or proposition which is regarded as being self-evidently true.

What is an Axiom?

What is the probability that 2 friends have their birthdays on the same day? 1/360 1/3652 1/365 1-(364/365)2

Probability Two Friends Same Birthday

The last United Nations Climate Change Conference was referred to as “COP26”. What is COP an abbreviation of? Conference of Parties Concerns of People Climate on Precipice Congress of Preservation

What Does COP Stand For in COP26?

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