The helicase of TFIIH hydrolyzes the β-γ bond of ATP to catalyze open complex formation at Pol II promoters. ATP hydrolysis is also required by a step subsequent to transcription initiation, most likely promoter clearance. Transcriptional activation by TFIIH was assayed on linear and circular templates either in the presence of ATP and GTP or the nonhydrolyzable nucleotide analogs AMP-PNP and GMP-PNP with RNA Polymerase I. The following results were obtained. Choose plausible explanation for these results. 

A. ATP is required under conditions where TFIIH is indispensable for initiation. These conditions include transcription from promoters containing a short stretch of mismatched base pairs surrounding the transcriptional start site as well as on negatively supercoiled templates.

B. As Pol I transcription on linear templates requires neither ATP hydrolysis nor protein phosphorylation

C. in contrast to Pol II, the topology of the template does not affect the requirement for TFIIH and neither the ATPase, helicase, nor protein kinase activity of TFIIH are required for Pol I transcription activation.

#Question id: 4732

#Unit 8. Inheritance Biology

What is F2 phenotype ratio observed when a homozygous recessive mutation in either or both of two different genes results in the same mutant phenotype?

#Question id: 4733

#Unit 8. Inheritance Biology

If a homozygous plant with red peppers is crossed with a homozygous plant with green peppers, all the F1 plants have red peppers. When the F1 are crossed with one another, the F2 are in a ratio of 9 red : 3 brown : 3 yellow : 1 green  due to

#Question id: 4734

#Unit 8. Inheritance Biology

If a homozygous plant with red peppers is crossed with a homozygous plant with green peppers, all the F1 plants have red peppers When the F1 are crossed with one another then produced following progeny Which of following interaction involved in gene to gene of peppers plant?

#Question id: 4735

#Unit 8. Inheritance Biology

In corn, three dominant alleles, called A, C, and R, must be present to produce colored seeds. Genotype A/–; C/– ; R/– is colored; all others are colorless. A colored plant AaCCRr is crossed with colorless plant aaCcRr. What proportional of offspring plant with colorless seed?

#Question id: 4736

#Unit 8. Inheritance Biology

A snapdragon plant that bred true for white petals was crossed to a plant that bred true for purple petals, and all the F1 had white petals. The F1 was selfed. Among the F2, three phenotypes were observed in the following numbers

white                              240

solid-purple                    61

spotted-purple                19

Total                              320

Which of the following reason to deviation f2 phenotype ratio ?

#Question id: 4737

#Unit 8. Inheritance Biology

Two independent pure line varieties having white and green phenotype in their fruit were cross, the all f1 progeny is white fruit. The F2 progeny obtain from selfing show white, yellow and green in ratio of 12:3:1. Which of the following is correct?