Queation t in chromatin DNA is bound to proteins which regulate its packaging an
ID: 218564 • Letter: Q
Question
Queation t in chromatin DNA is bound to proteins which regulate its packaging and also access to the sequence/gene ofornation Which of the following accurately describes nucleosomes? A This is a structure found predominantly in the nucleolus. B Histone proteins form the core of the nucleosome around which the DNA is wound C Histone proteins can be chemically modified by enzymes, and these modifications affect how "ighty or loosely" the DNA is associated with the core. D Two of the above All of the above Question i2 You conducted a modifier screen for mutants that affect the PEV eye color phenotype and identified a e(var) mutant This means that for this mutant Athere are more white eye cells in the eyes of the mutant fies as onpred to the ental PEV mutant flies B the spread of heterochromatin is decreased C the locus for the iohite gene has been inverted and is now closer to the euchromatin in the telomeric region of the chromosome D Two of the above E Al of the above Question 3 Bacteria with mutations in the lac operon and related genes have been created in you the mutants, you note that the operon is constantly transcribed and is increased in the absence of glcose You conclude that the mutation is likely to be in analysis of one of A he gene that codes for CAP B the operator (lacO) c the repressor (lad) e D Two of the above E All of the above Question 4 which of the following involved in the bensing of tryptophan levels A Attenuator sequence Region 1 Attenuator sequence Region 2 Attenuator sequence Region 3 0 Attenuator sequence Region 4 C E The two trp codons in the leader regionExplanation / Answer
1.Answer - D. Two of the above
B and C
Nucleolus is a part where rRNA is synthesis so it won't come.
2. E. All of the above
3. D - Two of the above
B and C
The operator and repressor are constitutively express if it undergoes mutation.
4. E - The two trp codon in the leader region
The two tryptophan codons make translation of the leader polypeptide sequence quite sensitive to the concentration of charged tRNATrp. If tryptophan is limiting, there will be insufficient charged tRNATrp and translation will pause at the tryptophan codons.