All of the following statements concerning repetitive DNA are correct EXCEPT Sel
ID: 204514 • Letter: A
Question
All of the following statements concerning repetitive DNA are correct EXCEPT Select one: a. tandemly repetitive DNA accounts for 10-15 % of mammalian DNA. b. The lengths of tandemly repetitive units are generally 100-100,000 nucleotides long Oc. Tandemly repetitive DNA is also known as satellite DNA O d. Interspersed repetitive DNA accounts for 25-40% of mammalian DNA. The attachment of -coCH3 to the amino acids of histones is called Select one: 0 a. histone methylation. b. histone acetylation. O c. promoter recognition. O d. codon recognition. Which of the following is an example of a posttranslational control? Select one: O a. A proteosome recognizes a ubiquitin molecule and degrades the protein molecule to which it is attached. O b. The addition of a cap and a tail to a newly synthesized mRNA transcript. O c. Deactivation of initiation factors. O d. An activator binds to an enhancer.Explanation / Answer
1) Option b is correct answer.
Tandemply repetitive DNA is usually 1-10bp long, Interspersed repetitive DNA is 100-10,000bp long.
2) Option b is correct answer.
-COCH3 is the acetyl group and its addition to amino acids of histone is termed as acetylation and it is a type of epigenetic modification.
3) Option a is correct.
Post-translational regulation is performed either by means of reversible events (posttranslational modifications, such as phosphorylation or sequestration) or by means of irreversible events (proteolysis). A proteosome recognizes a ubiquitin molecule and degrades the protein molecule to which it is attached.