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TLS Online TPP Program

#Question id: 40212

Read the following statements regarding the steps of a standard PCR cycle and choose the correct option.

Statement I: The denaturation step involves the breaking of phosphodiester bonds to separate the double-stranded DNA into single strands.

Statement II: The annealing temperature is usually set 3 -5 0   C lower than the melting temperature (Tm) of the primers to ensure specific binding.

#Applied Microbiology
  1. Both Statement I and Statement II are correct.
  2. Both Statement I and Statement II are incorrect.
  3. Statement I is correct, but Statement II is incorrect.
  4. Statement I is incorrect, but Statement II is correct.
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TLS Online TPP Program

#Question id: 40209

#Applied Microbiology

The process by which ATP is synthesized using the energy released by the flow of protons (H+) across a membrane down their electrochemical gradient is known as:
TLS Online TPP Program

#Question id: 40210

#Applied Microbiology

Match the PCR step in Column I with the correct temperature range or characteristic in Column II.

Column I (PCR Step)               Column II (Condition / Event)
A. Denaturation1. ∼72 °C; Optimum for Taq polymerase activity
B. Annealing2. ∼94 °C; Hydrogen bonds break to separate DNA strands
C. Extension3. ∼4 °C; Short-term storage after cycling
D. Final Hold4. ∼50–65 °C; Primers bind to the template
TLS Online TPP Program

#Question id: 40211

#Environmental Science

 Match the scientists in List I with their proposed theories or experiments in List II.

List I (Scientists)List II (Theories/Experiments)
A. A.I. Oparin & J.B.S. HaldaneI. Swan-necked flask experiment (Biogenesis)
B. S.L. Miller & H.C. UreyII. Coacervate droplets (Chemical Evolution)
C. Louis PasteurIII. Microspheres (Thermal synthesis of proteins)
D. Sidney FoxIV. Simulation of primitive earth conditions
TLS Online TPP Program

#Question id: 40213

#Applied Microbiology

In the following question, a statement of Assertion (A) is followed by a statement of Reason (R).

Assertion (A): The annealing step must be performed at a significantly lower temperature than the denaturation step.

Reason (R): High temperatures destabilize hydrogen bonds, while lower temperatures favor the formation of hydrogen bonds required for primers to hybridize with the template.
TLS Online TPP Program

#Question id: 40214

#Applied Microbiology

Which of the following represents the correct sequence of temperature changes during one single cycle of PCR amplification? 
TLS Online TPP Program

#Question id: 40215

#Environmental Science

Match the geological eons/events in List I with the biological milestones in List II.

List I (Time Period/Event)List II (Biological Milestone)
A. 4.0 - 3.8 Billion years agoI. Appearance of first Eukaryotes
B. 3.5 Billion years agoII. Oxygen Revolution (Great Oxidation Event)
C. 2.7 - 2.5 Billion years agoIII. Appearance of first cellular life (Prokaryotes)
D. 2.0 - 1.5 Billion years agoIV. Formation of life precursors (RNA/Protocells)