TLS Online TPP Program

#Question id: 3274


The common edible frog of Europe is a hybrid between two species, Rana lessonae and Rana ridibunda. The hybrids were first described in 1758 and have a wide distribution, from France across central Europe to Russia. Both male and female hybrids exist, but when they mate among themselves, they are rarely successful in producing offspring. What can you infer from this information?

#Section 3: Genetics, Cellular and Molecular Biology
  1. Postzygotic isolation exists between the two frog species.

  2. Prezygotic isolation exists between the two frog species.

  3. These two species are likely in the process of fusing back into one species.

  4. The hybrids form a separate species under the biological species concept.

More Questions
TLS Online TPP Program

#Question id: 14316

#Section 5: Bioprocess Engineering and Process Biotechnology

Cellulomonas bacteria used as single-cell protein for human or animal food are produced from glucose under anaerobic conditions. All carbon in the substrate is converted into biomass; ammonia is used as nitrogen source. The molecular formula for the biomass is CHI.5600.54N0.16; the cells also contain 5% ash. How does the yield of biomass from substrate in mass and molar terms compare with the maximum possible biomass yield?

TLS Online TPP Program

#Question id: 14317

#Section 5: Bioprocess Engineering and Process Biotechnology

system for manufacture of single-cell protein is Methylophilus methylotrophus. This organism is produced aerobically from methanol with ammonia as nitrogen source. The molecular formula for the biomass is CH 1.6800.36N0.22; these cells contain 6% ash. What is the maximum possible biomass yield from methanol?

TLS Online TPP Program

#Question id: 14318

#Section 5: Bioprocess Engineering and Process Biotechnology

system for manufacture of single-cell protein is Methylophilus methylotrophus. This organism is produced aerobically from methanol with ammonia as nitrogen source. The molecular formula for the biomass is CH 1.6800.36N0.22; these cells contain 6% ash. If the actual yield of biomass from methanol is 42% the thermodynamic maximum, what is the oxygen demand?

TLS Online TPP Program

#Question id: 14319

#Section 5: Bioprocess Engineering and Process Biotechnology

Both Saccharomyces cerevisiae yeast and Zymomonas mobilis bacteria produce ethanol from glucose under anaerobic conditions without external electron acceptors. The biomass yield from glucose is 0.11 g g-1 for yeast and 0.05 g g-I for Z. mobilis. In both cases the nitrogen source is NH3. Both cell compositions are represented by the formula CH1.800.5N0.2. What is the yield of ethanol from glucose by Saccharomyces cerevisiae yeast?

TLS Online TPP Program

#Question id: 14321

#Section 5: Bioprocess Engineering and Process Biotechnology

Both Saccharomyces cerevisiae yeast and Zymomonas mobilis bacteria produce ethanol from glucose under anaerobic conditions without external electron acceptors. The biomass yield from glucose is 0.11 g g-1 for yeast and 0.05 g g-I for Z. mobilis. In both cases the nitrogen source is NH 3. Both cell compositions are represented by the formula CH 1.800.5N0.2. Compare actual yield with theoretical maximum for Zymomonas mobilis bacteria ?