A chromosome is discovered in which all of the transcripts originate from the same DNA strand. This implies that in this chromos
ome A. promoters are all oriented in the same direction
B. adjacent promoters are oriented in opposing directions
C. promoters are randomly oriented
D. none of the above
E. all of the above
The correct option is A. promoters are all oriented in the same direction
Explanation:
A gene consists of a base sequence that is transcribed (transcription unit), in addition to two sequences that are not transcribed and that weaken (promoter and termination signal). Transcription by RNA polymerase takes place sequentially and in order along the DNA strand. The starting point is framed by a promoter, which is "upstream" (in relation to the direction of transcription) and adjacent to the transcription unit and ensures that the RNA polymerase binds to the DNA coding strand instead right. If all of the transcripts originate from the same DNA strand, the promoters must be oriented in the same direction, like that the promotor is going to regulate the transcription or gene expression. Similarly, the sequence of the termination signal, located just "downstream" after the transcription unit, interrupts the advance of the polymerase and terminates the transcription.
The pesticide killed off all of the pest that weren't immune to it and the pests that were immune reproduced with each other creating offspring that were immune to it as well and so on this is a example of natural selection.