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TLS Online TPP Program

#Question id: 378

Which of the following statements about buffers is true?

#Unit 1. Molecules and their Interaction Relevant to Biology

  1. A buffer composed of a weak acid of pKa = 5 is stronger at pH 4 than at pH 6.

  2. At pH values higher than the pKa, the salt concentration is higher than that of the acid.

  3. The strongest buffers are those composed of strong acids and strong bases.

  4. When pH = pKa, the weak acid and salt concentrations in a buffer are equal.

More Questions
TLS Online TPP Program

#Question id: 10736

#Unit 10. Ecological Principles

Ecotones are:
TLS Online TPP Program

#Question id: 1340

#Unit 4. Cell Communication and Cell Signaling

Extracellular matrices are LEAST likely to play a major role in which of the following?
TLS Online TPP Program

#Question id: 4947

#Unit 11. Evolution and Behavior

The first genes on Earth were probably
TLS Online TPP Program

#Question id: 2636

#Unit 2. Cellular Organization

Which of the following events occur when E. coli is starved for tryptophan?

I.  The ribosome translates leader peptide completely

II. Transcription reads through attenuator into trp EDCBA

III. Tryptophanyl tRNA is not formed

IV. A stem loop structure involving regions 3 and 4 is formed at attenuator site
TLS Online TPP Program

#Question id: 18672

#Unit 13. Methods in Biology

Larger DNA fragments up to 2 × 10 3 kb can be separated by using