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#Question id: 3632

geneticist is working with a new bacteriophage called phage Y3 that infects E. coli. He has isolated eight mutant phages that fail to produce plaques when grown on E. coli strain K. To determine whether these mutations occur at the same functional gene, he simultaneously infects E. coli K cells with paired combinations of the mutants and looks to see whether plaques are formed. He obtains the following results. (A plussign means that plaques were formed on E. coli K; a minussign means that no plaques were formed on E. coli K.)

How many cistron belong to these mutation?

#Unit 8. Inheritance Biology

  1. 2

  2. 6

  3. 4

  4. 3

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#Question id: 11475

#Unit 7. System Physiology – Animal

Rods exposed to light will ________.
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#Question id: 6613

#General Aptitude

What is the next number ; 34, 7, 37, 14, 40, 28, 43,…
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#Question id: 12718

#Unit 6. System Physiology – Plant

primary disruptions could be signaling the plant that a change in environmental conditions has occurred and that it’s time to respond by altering existing pathways or by activating stress-response pathways. At least five different types of stress-sensing mechanisms can be distinguished:

                       

                          COLUMN I

 

 

                              COLUMN II

 

A) Physical sensing

 

 

i) usually results from the detection of by-products that accumulate in cells due to the uncoupling of enzymatic or electron transfer reactions, such as the accumulation of ROS during stress caused by too much light.

 

 

B) Biophysical sensing

 

 

ii) often involves the presence of specialized proteins that have evolved to sense a particular stress; for example, calcium channels that can sense changes in temperature and alter Ca2+ homeostasis.

 

 

C) Metabolic sensing

 

 

iii) refers to modifications of DNA or RNA structure that do not alter genetic sequences, such as the changes in chromatin that occur during temperature stress.

 

 

D) Biochemical sensing

 

 

iv) refers to the mechanical effects of stress on the plant or cell structure, for example, the contraction of the plasma membrane from the cell wall during drought stress.

 

 

E) Epigenetic sensing

 

 

v) might involve changes in protein structure or enzymatic activity, such as the inhibition of different enzymes during heat stress.

 

 

  
Match the correct sequence sensing mechanism during in stress;
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#Question id: 10437

#Unit 6. System Physiology – Plant

Phytochrome-mediated control of photomorphogenesis is linked to many other gene functions. The following statements are made on the mechanism of phytochrome action:

a) COP1, negative regulator of photomorphogenesis, is a component of the E3 ubiquitin ligase complex that targets photomorphogenesis-promoting proteins for degradation such as phyA

b) Light-dependent export of COP1 to the cytoplasm is a slow process, requires long exposure to light

c) The absence of COP1 in the cytosol permits the accumulation of transcriptional activators necessary for photomorphogenic development

d) The COP1–SPA1-E3 ligase complex is also responsible for the ubiquitination and proteasomal degradation of photomorphogenesis-promoting proteins, such as HY5

Which one of the following combinations is correct?
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#Question id: 19469

#Unit 12. Applied Biology

Glyphosate is extensively and rapidly metabolised by glyphosate oxidoreductase (gox), which breaksdown glyphosate into