Bioinformatics Practice Test 3

1. Which of the following about the Gibbs sampler is untrue?

It is a statistical method for finding motifs in sequences

It can find the optimal width and number of given motifs in each sequence

It searches for the statistically most probable motifs

It is dissimilar to the principle of the EM method

2. Which of the following is not correct about the Integral Membrane Proteins?

Most typical transmembrane segments are α-helices

The exterior of the proteins spanning the membrane must be very hydrophobic to be stable

The exterior of the proteins spanning the membrane must be very hydrophilic to be stable

Membrane proteins exist in lipid bilayers of cell membranes

3. Which of the following is not a benefit of BLAST?

More sensitive

Statistical rigor

Speed

Handling of gaps

4. The peptide formation involves two amino acids covalently joined together between the carboxyl group of one amino acid and the amino group of another.

True

False

5. Which of the following is not correct about the α-Helices?

An α-helix has a main chain backbone conformation that resembles a corkscrew

Nearly all known α-helices are right handed, exhibiting a rightward spiral form

Nearly all known α-helices are right handed, exhibiting a leftward spiral form

In right handed helix, there are 3.6 amino acids per helical turn

6. The pattern searching method type of analysis was performed on groups of related proteins, and the amino acid patterns that were located may be found in the Prosite catalog.

True

False

7. TBLASTX queries protein sequences to anucleotide sequence database with the sequences translated in all six reading frames.

True

False

8. The last step is to perform a statistical evaluation of the final alignment as in BLAST, which produces the E-value.

True

False

9. The use of low-complexity masking in the BLAST procedure means that it may have higher specificity than FASTA because potential false positives are reduced.

True

False

10. The initiation of FASTA format has ____ symbol.