Which of the following statements about polymerase chain reaction is correct?

a) PCR denaturation temperature calculated by using Y = X (1+E)n

b) Size of the primer negatively affects the efficiency of PCR

c) Standard PCR doesn’t efficiently amplify sequence much longer than about 5kb.

d) Primer annealing of PCR at 550C for 1.5 min.

e) Time taken for each cycle of PCR considerably longer than 3 min.

#Question id: 1810

#Unit 4. Cell Communication and Cell Signaling

Allelic exclusion is not seen for:

#Question id: 1770

#Unit 4. Cell Communication and Cell Signaling

Which of the following immunoglobulin has the highest avidity of the immunoglobulins?

#Question id: 8687

#Unit 9. Diversity of Life Forms

Your professor wants you to construct a phylogenetic tree of orchids. She gives you tissue from seven orchid species and one lily. What is the most likely reason she gave you the lily?

#Question id: 11721

#Unit 6. System Physiology – Plant

The induction of α-amylase synthesis in barley aleurone layers by gibberellin, given some statements about after the induction of GA into the aleurone layer, and allows some transcriptional gene function inside the nucleus such as;

a) GA-MYB is a negative regulator of α-amylase transcription

b) The sequence of the gibberellic acid response element (GARE) in the α-amylase gene promoter is similar to the DNA sequence to which MYB proteins bind.

c) Synthesis of GA-MYB mRNA begins to increase as early as 1 h after gibberellin treatment, preceding the increase in a-amylase mRNA by several  hours

d) A mutation in the GARE that prevents MYB binding also prevents  α-amylase expression.

e) GA-MYB can therefore be defined as a primary or early response gene, while the α-amylase gene is a secondary or late response gene

f) The secretory pathway requires GA stimulation of the calcium-calmodulin– independent pathway.

Which of the following statements is incorrect about this transcriptional gene?

#Question id: 4152

#Unit 3. Fundamental Processes

The pathway for polypeptides exported from E. coli includes the following steps, which occur in what order for correct export?

1.  A chaperone, SecA, binds to the polypeptide.

2.  A chaperone, SecB, binds to the polypeptide.

3.  ATP is hydrolyzed by Sec A.

4.  SecA pushes 20 amino acids of the polypeptide into the translocation complex.