Fragments of DNA have been extracted from the remnants of extinct wooly mammoths, amplified, and sequenced. These can now be used to

#Question id: 10363

#Unit 6. System Physiology – Plant

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: 10365

#Unit 6. System Physiology – Plant

Why the nitrogenase enzymes catalyzes the nitrogen fixation reaction only in microanaerobic or anaerobic conditions?

#Question id: 10366

#Unit 6. System Physiology – Plant

Cyanobacteria can fixes nitrogen in an anaerobic conditions. Which of the following statements about heterocyst which is specialized cell of blue-green algae is incorrect?

#Question id: 10367

#Unit 6. System Physiology – Plant

Cyanobcteria also fixes nitrogen under anaerobic conditions without  heterocyst where?

#Question id: 10368

#Unit 6. System Physiology – Plant

Free-living bacteria that are capable of fixing nitrogen are aerobic, facultative, or anaerobic. Some of the Aerobic nitrogen-fixing bacteria such as

#Question id: 10369

#Unit 6. System Physiology – Plant

Which type of the nitrogen-fixing bacteria are thought to maintain a low oxygen concentration (microaerobic conditions) through their high levels of respiration