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TLS Online TPP Program

#Question id: 101

You have two bottles, each of which contains a white, crystalline substance. Your lab director tells you that one contains lactose and the other sucrose. Your job is to determine which bottle contains which sugar. Which procedure would you use?

#Biochemistry

  1. Test both for solubility in water. Sucrose is very soluble; lactose is only minimally soluble.

  2. Test for the ability to reduce Ag+. Only lactose will react.

  3. Dissolve each in water and record the pH. Lactose is far more acidic than sucrose.

  4. React each with bromine (Br2) water. Only sucrose will react.

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TLS Online TPP Program

#Question id: 40207

#Environmental Science

Assertion (A): The pH of normal rain is considered to be exactly 7.0 (Neutral).
Reason (R): Carbon dioxide (CO2) in the atmosphere dissolves in raindrops to form weak carbonic acid.
TLS Online TPP Program

#Question id: 40208

#Environmental Science

Given below are two statements:
Statement I: Under the Environmental Impact Assessment (EIA) Notification 2006, "Category A" projects require clearance from the Central Government (MoEFCC).
Statement II: "Category B" projects do not require any Environmental Clearance from either State or Central authorities.
In light of the above statements, choose the correct answer:
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. Denaturation 1. ~72 °C; Optimum for Taq polymerase activity
 B. Annealing 2. ~94 °C; Hydrogen bonds break to separate DNA strands 
 C. Extension 3. ~4 °C; Short-term storage after cycling
 D. Final Hold 4. ~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: 40212

#Applied Microbiology

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.