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TLS Online TPP Program

#Question id: 4703

Within a few weeks of treatment with the drug 3TC, a patientʹs HIV population consists entirely of 3TC-resistant viruses. How can this result best be explained?

#Unit 11. Evolution and Behavior

  1. HIV can change its surface proteins and resist vaccines.

  2. The patient must have become reinfected with 3TC-resistant viruses.

  3. HIV began making drug-resistant versions of reverse transcriptase in response to the drug.

  4. A few drug-resistant viruses were present at the start of treatment, and natural selection increased their frequency.

More Questions
TLS Online TPP Program

#Question id: 1959

#Unit 4. Cell Communication and Cell Signaling

How do people contract salmonella poisoning?
TLS Online TPP Program

#Question id: 30115

#Unit 1. Molecules and their Interaction Relevant to Biology

The antibacterial trimethoprim is an inhibitor of 
TLS Online TPP Program

#Question id: 11997

#Unit 10. Ecological Principles

Which statement best contrasts environmentalism with ecology?
TLS Online TPP Program

#Question id: 13103

#Unit 13. Methods in Biology

With the help of DNA fingerprinting which can be used to determine paternity. There are three babies (Baby A, Baby B and Baby C) in a maternity ward, and three sets of confused and worried parents. (Father and Mother #1 are a couple, as are Father and Mother #2, and Father and Mother #3.) 
You do each PCR reaction and load each one into a separate well of an agarose gel, and then run the gel.
 
 

Why is it that some people show only one band?
TLS Online TPP Program

#Question id: 11329

#Unit 10. Ecological Principles

Which of the following aquatic systems is like a tropical rain forest because of its richness of biological production and diversity of inhabitants?