_____________ : the transfer of the genetic information from DNA to RNA
transcription
_______________ : the transfer of information from RNA to protein. In addition, genetic information flows from RNA to DNA during the conversion of the genomes of RNA tumor viruses to their DNA proviral forms
translation
________________ is the specification of amino acids by nucleotide triplets called ___________ in the gene transcript.
genetic code
codons
Translation takes place on intricate macromolecular machines called __________________, which are composed of three to five RNA molecules and 50 to 90 different proteins.
ribosomes
The RNA molecules that are translated on ribosomes are called ___________________
messenger RNAs (mRNAs)
______________________ are small RNA molecules that function as adaptors between amino acids and the codons in mRNA during translation.
Transfer RNAs (tRNAs)
___________________ are structural and catalytic components of the ribosomes, the intricate machines that translate nucleotide sequences of mRNAs into amino acid sequences of polypeptides
Ribosomal RNAs (rRNAs)
__________________________ are structural components of spliceosomes, the nuclear organelles that excise introns from gene transcripts.
Small nuclear RNAs (snRNAs)
_________________________ are short 20- to 22-nucleotide single-stranded RNAs that block the expression of complementary or partially complementary mRNAs by either causing their degradation or repressing their translation.
Micro RNAs (miRNAs)
template strand
nontemplate strand = coding strand
RNA polymerase
An enzyme that links together the growing chain of RNA nucleotides during transcription, using a DNA strand as a template.
RNA polymerases bind to specific nucleotide sequences called ______________, and with the help of proteins called transcription factors, initiate the synthesis of RNA molecules at transcription start sites.
promoters
RNA polymerase
RNA synthesis takes place within a locally unwound segment of DNA, sometimes called a _____________________________, which is produced by RNA polymerase
transcription bubble
The process of transcription can be divided into three stages:
(1) initiation of a new RNA chain, (2) elongation of the chain, and (3) termination of transcription and release of the nascent RNA molecule
Termination of RNA chains occurs when RNA polymerase encounters a _______________________.
termination signal
5' cap
Cover that is added to the 5' end of mRNA before mRNA leaves the nucleus
poly(A) tail
a string of adenine nucleotides added to mRNA after transcription
intron
sequence of DNA that is not involved in coding for a protein
exon
expressed sequence of DNA; codes for a protein
The resulting DNA-RNA hybrid structures will contain single-stranded regions of DNA called _________________, where RNA molecules have displaced DNA strands to form DNA-RNA duplex regions.
R-loops