Gene Regulation and RNA Synthesis

DnaA proteins bind to the oriC, causing bending and separation of the A-T rich DNA strands.

DNA polymerase I removes RNA primers and fills the gaps with DNA.

DNA ligase forms a phosphodiester bond between the 3'-hydroxyl of one strand and the 5'-phosphate of an Okazaki fragment.

<p>DNA polymerase III has exonuclease activity that removes mismatched bases from the 3' end of the growing strand.</p> Signup and view all the answers

<p>Termination occurs when the Tus protein reaches the termination site (ter) on the DNA.</p> Signup and view all the answers

<p>Eukaryotes use the enzyme telomerase to extend their chromosomes at the ends.</p> Signup and view all the answers

<p>The promoter functions as the recognition site for RNA polymerase and orients it for transcription.</p> Signup and view all the answers

<p>The Shine-Dalgarno sequence is important for the initiation of translation in bacteria.</p> Signup and view all the answers

<p>Coding genes directly encode proteins or RNA, while regulatory genes control the expression of other genes.</p> Signup and view all the answers

<p>tRNA genes may code for multiple tRNA types, while rRNA genes are transcribed as large precursors.</p> Signup and view all the answers

<p>Inverted repeats play a role in gene regulation, DNA replication, and recombination processes.</p> Signup and view all the answers

<p>The three types of RNA produced are mRNA, tRNA, and rRNA.</p> Signup and view all the answers

<p>The sigma factor helps the core RNA polymerase recognize the start of genes.</p> Signup and view all the answers

<p>During elongation, RNA polymerase unwinds DNA and transcribes mRNA from the template strand.</p> Signup and view all the answers

<p>Polycistronic mRNA contains directions for multiple polypeptides and is catalyzed by a single RNA polymerase.</p> Signup and view all the answers

<p>The Shine-Dalgarno sequence aligns mRNA with the ribosomal RNA for initiation of protein synthesis in bacteria.</p> Signup and view all the answers

<p>The ribosome serves as the site for translation, facilitating the assembly of amino acids into polypeptides.</p> Signup and view all the answers

<p>Wobble refers to the loose base pairing at the third position of the codon, allowing multiple codons to code for the same amino acid.</p> Signup and view all the answers

<p>Release factors recognize stop codons and facilitate the dissociation of the ribosome, terminating translation.</p> Signup and view all the answers

<p>Aminoacyl-tRNA synthetases catalyze the attachment of amino acids to their corresponding tRNA.</p> Signup and view all the answers

<p>Protein maturation is the process by which a newly synthesized protein undergoes folding and modifications to achieve its functional form.</p> Signup and view all the answers

<p>Inteins are segments of a polypeptide that are removed during splicing, while exteins are the remaining portions that remain in the final protein.</p> Signup and view all the answers

<p>16S rRNA binds to the Shine-Dalgarno sequence on mRNA, facilitating the proper alignment of the ribosome for translation initiation.</p> Signup and view all the answers

<p>The Sec-dependent pathway translocates pre-proteins across or into the plasma membrane of bacteria.</p> Signup and view all the answers

<p>Chaperone proteins, such as SecB, keep pre-proteins unfolded during their translocation across the membrane.</p> Signup and view all the answers

<p>The Tat system transports folded proteins, while the Sec-dependent pathway translocates unfolded pre-proteins.</p> Signup and view all the answers

<p>Type I secretion systems are related to ABC transport systems and secrete proteins directly from the cytoplasm to the external environment.</p> Signup and view all the answers

<p>Type IV secretion systems secrete proteins and DNA from one bacterium to another, particularly during conjugation.</p> Signup and view all the answers

<p>Type III secretion systems are sec-independent and utilize injectisomes to deliver virulence factors directly into host cells.</p> Signup and view all the answers

<p>Type V secretion systems are considered autotransporters, as they transport themselves across the membrane.</p> Signup and view all the answers

<p>SecY, SecE, and SecG form a channel in the membrane that facilitates the translocation of pre-proteins.</p> Signup and view all the answers

<p>Type VI secretion systems resemble bacteriophage genome injection systems in their functionality.</p> Signup and view all the answers

<p>Types II, III, and V secretion systems are unique to Gram-negative bacteria.</p> Signup and view all the answers