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TLS Online TPP Program

#Question id: 341

 Which force can stabilize a DNA double-helix?

#Unit 1. Molecules and their Interaction Relevant to Biology

  1. Hydrophobic bases are found in the interior of the helix where each base-pair is stabilized by the same number of hydrogen bonds.

  2. Hydrophilic sugar-phosphate groups are found on the exterior of the helix where they can interact with water.

  3. Non-covalent N-glycosidic bonds can form between nitrogenous bases in opposite strands in the helix.

  4. Covalent base-stacking interactions can occur between adjacent bases within the same strand in the helix.

More Questions
TLS Online TPP Program

#Question id: 9237

#Unit 9. Diversity of Life Forms

Which of the following factors causes extremely high levels of toxic chemicals in fish-eating birds?
TLS Online TPP Program

#Question id: 9238

#Unit 9. Diversity of Life Forms

Which of the following is a consequence of biological magnification?
TLS Online TPP Program

#Question id: 9239

#Unit 9. Diversity of Life Forms

Why are changes in the global carbon cycle important?
TLS Online TPP Program

#Question id: 9240

#Unit 9. Diversity of Life Forms

Use the following figure to answer the question.


Looking at the figure, what can you conclude about the data?
TLS Online TPP Program

#Question id: 9241

#Unit 9. Diversity of Life Forms

The main goal of sustainable development is to ________.
TLS Online TPP Program

#Question id: 9242

#Unit 9. Diversity of Life Forms

Eutrophication is often caused by excess limiting-nutrient runoff from agricultural fields into aquatic ecosystems. This process results in massive algal blooms that eventually die and decompose, ultimately depleting the dissolved oxygen, killing large numbers of fish and other aquatic organisms. Predict which of the following human actions would best address the problem of eutrophication near agricultural areas?