Which of the following is transmembrane proteins?

#Question id: 2851

#Unit 2. Cellular Organization

There is a growing body of evidence that acetylation of histone N-termini in specific chromosomal regions contributes to gene control by regulating the binding of histones to DNA and regulation of the folding state of chromatin. The extent of histone acetylation is correlated with the relative resistance of chromatin DNA to digestion by nucleases. Which combination of histone acetylation state and DNAse 1 resistance is characteristic of actively transcribed regions of chromatin?

#Question id: 2852

#Unit 2. Cellular Organization

The chromosomal karyotypes of two species of small deer, the Reeves muntjac and the Indian muntjac, are strikingly different despite the fact that the two genomes contain about the same amount of DNA. However, within a species, there are properties of chromosomes that are the same, i.e. species-specific. Select the answer that contains all of these species-specific properties of chromosomes at metaphase

#Question id: 2853

#Unit 2. Cellular Organization

Not all bacteria need to maintain their DNA in a negatively supercoiled state. Bacteria that prefer to grow at very high temperatures must expend energy. Which of the following observation found to be true?

A. Bacteria don’t need to expend energy to prevent their DNA from unwinding due to thermal denaturation

B. These bacterial organisms have a different topoisomerase called reverse gyrase

C. Reverse gyrase decrease the linking number of relaxed DNA in the presence of ATP

#Question id: 2854

#Unit 2. Cellular Organization

Negatively charged phosphate groups in the DNA backbone must be neutralized in order for folding of DNA to occur. In bacterial DNA, this charge neutralization is carried out by small positively charged molecules called polyamines. What proteins carry out this same function in eukaryotic cells?

#Question id: 2855

#Unit 2. Cellular Organization

Which statements are correct about lac operator;

I. The site bound by the Lac repressor.

II. The lac operator overlaps the promoter, and so the repressor bound to the operator physically prevents RNA polymerase from binding to the promoter and thus inhibit the RNA synthesis.

III. Have 21-bp sequence with twofold symmetric and is recognized by four subunits of Lac repressor, two binding to each half-site.

IV. CAP binds as a dimer to a site similar in length to that of the lac operator, but different in sequence. This site is located some 60 bp upstream of the start site of transcription.

#Question id: 2856

#Unit 2. Cellular Organization

Match the lac genes with their enzymes & functions;