#Question id: 27405
#Unit 1. Molecules and their Interaction Relevant to Biology
#Question id: 2883
#Unit 2. Cellular Organization
Which, if any, of the following statements is incorrect?
I. In X-chromosome inactivation, the inactivated X chromosome is epigenetically silenced by a transcript, the XIST RNA, that is produced from the active X chromosome.
II. The XIST RNA works by coating most of the X chromosome that is to be inactivated and then recruiting Polycomb proteins to condense the chromosome.
III. The inactivated X chromosome carries the kinds of histone modification that are typical of heterochromatin.
IV. The pattern of X-chromosome inactivation is made randomly but once it has been established the same pattern of X-inactivation is propagated through all mitotic and meiotic cell divisions.
#Question id: 12936
#Unit 13. Methods in Biology
#Question id: 4164
#Unit 3. Fundamental Processes
Which help cells avoid mis-insertion of amino acids in protein synthesis?
#Question id: 4241
#Unit 3. Fundamental Processes
Use the figure to answer the question. The tRNA shown in the figure has its 3′ end projecting beyond its 5′ end. Which of the following processes will occur at this 3′ end?