Question

1a. An enhancer may be located far away from the gene it regulates, or even downstream of it or within introns.

1b. Which of the following is true of spliceosomes? Select all that apply.

		They are made up of proteins and RNA
		They are present in both bacteria and eukaryotes
		They are always required to remove introns
		Their function is to remove introns from pre-mRNA molecules

Fill in the blank(s)

1c. If a gene is always turned on in a cell, it is known as ____.

1d. The rho factor is involved in ____ of____ in some genes.

Answer 1

1a. An enhancer may be located upstream or downstream of the gene it regulates. Furthermore, an enhancer doesn't need to be located near the transcription initiation site to affect transcription, as some have been found located in several hundred thousand base pairs upstream or downstream of the start site.

1b. A spliceosome is a large and complex molecular machine found primarily within the nucleus of eukaryotic cells. they are generally absent in prokaryotes.

the spliceosome is assembled from small nuclear RNAs and approximately 80 proteins.

the spliceosome removes introns from a transcribed pre-mRNA, a type of primary transcript.

1c. If a gene is always turned on in a cell, it is known as  constitutive gene or unregulated gene.

1d. The rho factor is involved in termination of transcription in some genes.