Precision will be reduced, but yield will be increased

Optimisation of a PCR reaction is often a compromise between the competing demands for precision, efficiency and yield. Although the specific effects may vary, generally, increasing the annealing temperature will increase non-specific primer binding and reduce precision. Increasing the length of the elongation phase will reduce the proportion of incomplete newly-synthesised strands and therefore increase yield. In this case, the potential effect on efficiency is unclear. Increasing the elongation phase would increase the reaction time, but the time taken to ramp down to a lower annealing temperature would be reduced.

Which of the following will provide least specific amplification in qPCR?

TLS Online TPP Program

#Question id: 33472

#Unit 2. Cellular Organization

Find correct True and False statements

A. Human females have 23 different chromosomes, whereas human males have 24.

B. In the living cell, chromatin usually adopts the extended “beads-on-astring” form.

C. The four core histones are relatively small proteins with a very high proportion of positively charged amino acids; the positive charge helps the histones bind tightly to DNA, regardless of its nucleotide sequence.

D. Nucleosomes bind DNA so tightly that they cannot move from the positions where they are first assembled.

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#Question id: 33473

#Unit 2. Cellular Organization

Which of the following specialized DNA sequences and their functions that act to ensure that the number and morphology of chromosomes are constant from one generation of a cell to the next.

 Replication origins B. Centromeres C. Telomeres

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#Question id: 33474

#Unit 2. Cellular Organization

CTG/CAG trinucleotide repeats (5ʹ- CTG in one strand and 5ʹ-CAG in the other strand) is unusually flexible. What can be their probable role?

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#Question id: 33475

#Unit 2. Cellular Organization

With pulsed-field gel electrophoresis, which can separate DNA molecules up to 107 bp in length. The results of pulsed-field gel electrophoresis of the DNA from the yeast Saccharomyces cerevisiae are shown in Figure. How many chromosomes does S. cerevisiae have?

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#Question id: 33476

#Unit 2. Cellular Organization

Find true and false statements

A. The structures of eukaryotic genes show extensive variation. 

B. Some eukaryotic genes are uninterrupted and their sequences are colinear with those of the corresponding mRNAs. 

C. Most multicellular eukaryotic genes are interrupted, but the introns vary enormously in both number and size.

TLS Online TPP Program

#Question id: 33477

#Unit 2. Cellular Organization

Finding: Ancestry have similar organizations with conservation of the positions (of at least some) of the introns.

Example: The globin and DHFR genes are examples of a genes that share a common ancestor