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#Question id: 15954

some given other factors are reported to affect Somatic embryo (SE) regeneration such as
a) high K+ levels and low dissolved O2  levels promote SE regeneration
b) some volatile compounds like ethanol promote SE regeneration
c) low sucrose concentrations inhibit SE regeneration
d) use of sucrose as carbon source improves both SE induction and maturation as compared to maltose 
Which of the following statement must not be true about SE regeneration?

#Unit 12. Applied Biology
  1. a and b
  2. b, c and d
  3. c and d
  4. a, b and c
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TLS Online TPP Program

#Question id: 18981

#Unit 13. Methods in Biology

The pL promoter is controlled by the cl repressor protein of bacteriophage A. In practice, a temperature-sensitive mutant of the cl repressor, cl857, is generally used to regulate pL-directed transcription. Cells carrying the temperature-sensitive cl repressor are first grown at 30°C, and 42°C
TLS Online TPP Program

#Question id: 13065

#Unit 13. Methods in Biology

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.
Agglutination of antigens by utilising specific antibodies can only occur, if
TLS Online TPP Program

#Question id: 797

#Unit 1. Molecules and their Interaction Relevant to Biology

With respect to microRNAs, which, if any, of the following statements, is FALSE?)

A. MicroRNA genes often occur in gene clusters within introns of protein-coding genes and are usually transcribed by RNA polymerase II.

B. Like an mRNA a miRNA is initially produced as a larger precursor RNA that, like the great majority of mRNAs, usually has a 5’ cap and a poly(A) tail.

C. MicroRNAs are produced by germ-line cells only.

D. A miRNA is initially produced as a duplex RNA but in order to work it needs to be converted into a single-strand RNA.

E. MicroRNAs usually work as transcription factors.
TLS Online TPP Program

#Question id: 26407

#Unit 3. Fundamental Processes

Choose the correct regarding DNA Pol a/ primase and DNA Pold

a. They primarily act on the lagging strand

b. They primarily act on the leyding strand

c. They are only recruited after DNA unwinding

d. They are only recruited before DNA unwinding
TLS Online TPP Program

#Question id: 9151

#Unit 9. Diversity of Life Forms

What would be the effect on climate in the temperate latitudes if Earth were to slow its rate of rotation from a 24-hour period of rotation to a 48-hour period of rotation?