You have isolated two mutations that show decreased expression of the Lac operon. However, unlike like the promoter mutations, these mutations don’t respond to the inducer IPTG. These mutations, designated Lac3– and Lac4–, are evaluated for the quantity of ß-galactosidase and permease activity expressed with or without IPTG:

 

Mapping experiments reveal that Lac3– and Lac4– are different short deletions located in the region before the start of the LacZ gene. Given the data shown above suggest which genetic element(s) in addition to part of the promoter has been deleted in each mutant. 

#Question id: 10359

#SCPH05 I Biotechnology

Nitrate reductases of higher plants are composed of two identical subunits, each containing three prosthetic groups. Which of the following is not the prosthetic group of nitrate reductase;

#Question id: 10360

#SCPH05 I Biotechnology

How much ATP require in the nitrogen fixation or conversion of ammonium assimilation in the system?

#Question id: 10361

#SCPH05 I Biotechnology

The carbon skeleton for amino acids derives from 3-phosphoglycerate generated during glycolysis is called anaplueratic reaction. Generated amino acids from 3-PGA is that,

#Question id: 10362

#SCPH05 I Biotechnology

Bacteria can convert atmospheric nitrogen into ammonia, Several form symbiotic associations with higher plants is given below;

               HOST PLANT                                                                          N-FIXING SYMBIONTS

A) Gunnera                                                                            i) Frankia

      B) Azolla                                                                                ii) Acetobacter

C) Leguminous                                                                     iii) Azospirillum

             D) Actinorhizal                                                                      iv) Nostoc

             E) Sugarcane                                                                         v) Anabaena

             F) Miscanthus                                                                       vi) Sinorhizobium

Which of the following combination with the host plants and n-fixing symbionts is CORRECT?

#Question id: 10363

#SCPH05 I Biotechnology

Free living nitrogen fixing takes place as shown in the following;

             TYPE                                                                                       N-FIXING GENERA

A) Cyanobacteria (blue-green algae)                                        i) Bacillus

B) Aerobic                                                                                     ii) Clostridium

C) Facultative                                                                              iii) Anabaena

D) Anaerobic nonphotosynthetic                                            iv) Rhodospirillum

E) Anaerobic photosynthetic                                                     v) Azospirillum

 Which of the following combination of free living nitrogen fixing bacteria is correct?

#Question id: 10385

#I Life Science/ Life Sciences Group – I-V

The leaves of many species are able to bend toward the sun during its progress across the sky, a phenomenon known as