Practice Questions

  1. Home
  2. Free Resources
  3. Practice Questions
  4. 13488
TLS Online TPP Program

#Question id: 15417

Sequence of amphibian lens induction postulated by experiments on embryos of the frog Xenopus laevis ; EXCEPT

#Unit 5. Developmental Biology
  1. Unidentified inducers (possibly from the foregut endoderm and cardiac mesoderm) cause the synthesis of the Otx2 transcription factor in the head ectoderm during the late neurula stage.
  2. As the neural folds rise, inducers from the anterior neural plate (including the region that will form the retina) induce Pax6 expression in the anterior ectoderm that can form lens tissue.
  3. As the neural folds rise, inducers from the anterior neural plate (including the region that will form the retina) induce Pax6 expression in the anterior ectoderm that can form lens tissue.
  4. The optic vesicle secretes BMP and FGF family paracrine factors, which induce the synthesis of the Sox transcription factors and initiate observable lens formation
More Questions
TLS Online TPP Program

#Question id: 10362

#Unit 6. System Physiology – Plant

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?
TLS Online TPP Program

#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?
TLS Online TPP Program

#Question id: 10364

#Unit 6. System Physiology – Plant

Which of the following is the most common type of symbiosis occurs between members of the plant family and soil bacteria?
TLS Online TPP Program

#Question id: 10365

#Unit 6. System Physiology – Plant

Why the nitrogenase enzymes catalyzes the nitrogen fixation reaction only in microanaerobic or anaerobic conditions?
TLS Online TPP Program

#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?
TLS Online TPP Program

#Question id: 10367

#Unit 6. System Physiology – Plant

Cyanobcteria also fixes nitrogen under anaerobic conditions without  heterocyst where?