Biology Transcription & Translation

A ribosome has ____ binding sites for tRNA

3

Nucleotides are added to the _______ end of the growing RNA molecule.

3'

Transcription progresses at a rate of ______ nucleotides per second in eukaryotes.

40

The 5' end of pre-mRNA receives a modified nucleotide _____________.

5' cap

All ______ codons were deciphered by the mid-1960s

64

The central dogma of molecular biology

DNA--> RNA--> Proteins

__________ ____________ is the process by which DNA directs protein synthesis, includes two stages: transcription and translation

Gene expression

Eukaryotic cells modify ________ after transcription

RNA

________ is the bridge between genes and the proteins for which they code.

RNA

RNA synthesis is catalyzed by ________ __________________ which pries the DNA strands apart and hooks together the RNA nucleotides.

RNA polymerase

A gene can be transcribed simultaneously by several ________ ____________.

RNA polymerases

_______ ____________ removes introns and joins exons, creating an mRNA molecule with a continuous coding sequence.

RNA splicing

DNA makes _________ makes ____________

RNA; proteins

_______________ are the sites of translation in both prokaryotes and eukaryotes.

Ribosomes

A promoter called a __________ ________ is crucial in forming the initiation complex in eukaryotes.

TATA box

_________________ is the synthesis of RNA using information in DNA.

Transcription

________________ ___________ mediate the binding of RNA polymerase and the initiation of transcription.

Transcription factors

________________ is the synthesis of a polypeptide, using information in the mRNA.

Translation

During RNA processing, both ends of the primary transcript are usually ___________.

altered

The words of a gene are transcribed into three-nucleotide words of mRNA that are then translated into a chain of __________ _________, forming a polypeptide.

amino acids

tRNAs transfer __________ _______ to the growing polypeptide in a ribosome.

amino acids

Each molecule of tRNA has an ____________ on its other end; the anticodon base-pairs with a complementary codon on mRNA.

anticodon

During translation, the mRNA base triplets, called __________, are read in the 5' to 3' direction.

codons

RNA is ____________________ to the DNA template strand.

complementary

The coding nucleotide sequence of DNA and pre-mRNA are called ________ because they are expressed and usually translated into amino acid sequences.

eons

An organized unit of DNA sequences that enables a segment of DNA to be transcribed into RNA and ultimately results in the formation of a functional product is called a __________.

gene

Molecules of tRNA are not ____________.

identical

The noncoding nucleotide sequence of DNA and pre-mRNA is called __________

introns

In prokaryotes, translation of ________ can begin before transcription has finished.

mRNA

__________ is the operational code.

mRNA

Transcription produces _________________ ________ (_______)

messenger RNA (mRNA)

The genetic code is ___________ universal, shared by the simplest bacteria to the most complex animals.

nearly

Most eukaryotic genes and their RNA transcripts have long ____________ stretches of nucleotides that lie between coding regions.

noncoding

In a eukaryotic cell, the _____________ ______________ separates transcription from translation.

nuclear envelope

Transcription takes place in the _____________ of eukaryotes.

nucleus

The 3' end of pre-mRNA gets a ______________.

poly-A tail

Each codon specifies the amino acid (one of 20) to be placed at the corresponding position along a ________________.

polypeptide

Many proteins are composed of several _________________, each of which has its own gene.

polypeptides

Each end of a ______________ molecule is modified in a particular way.

pre-mRNA

Enzymes in the eukaryotic nucleus modify _____________ (RNA processing) before the genetic messages are dispatched to the cytoplasm.

pre-mRNA

The DNA sequence where RNA polymerase attaches is called the ______________; in bacteria, the sequence signaling the end of transcription is called the _______________.

promoter; terminator

Ribosomes facilitate specific coupling of tRNA anticodons with mRNA codons in ____________ ___________

protein synthesis

___________ is the part of the factory where assembly occurs.

rRNA

Codons must be read in the correct ____________ ___________ (correct groupings) in order for the specified polypeptide to be produced.

reading frame

The genetic code is _____________ (more than one codon may specify a particular amino acid) but not ambiguous; no codon specifies more than one amino acid.

redundant

The two ribosomal subunits (large and small) are made of proteins and _____________ _______ (_______)

ribosomal RNA (rRNA)

The template strand is always the _________ strand for a given gene.

same

Each molecule of tRNA carries a ___________ amino acid sequence on one end.

specific

Of the 64 triplets, 61 code for amino acids; 3 triplets are "________" signals to end translation.

stop

___________ is the amino acid shuttle and translator

tRNA

During transcription, one of the two DNA strands, called the ___________ _________, provides a template for ordering the sequence of complementary nucleotides in an RNA transcript.

template strand

RNA synthesis follows the same base-pairing rules as DNA, except that uracil substitutes for __________.

thymine

DNA makes RNA in the nucleus via ________________.

transcription

The process that produces mRNA from DMA is called _________________.

transcription

The two steps of protein synthesis:

transcription and translation

The completed assembly of transcription factors and RNA polymerase II bound to a promoter is called a ________________ ____________ _____________.

transcription initiation complex

The stretch of DNA that is transcribed is called a _______________ _______.

transcription unit

A cell translates an mRNA message into protein with the help of _____________ ______.

transfer RNA (tRNA)

RNA makes proteins (polypeptides) at the ribosome in the cytoplasm via ________________.

translation

The flow of information from gene to protein is based on a __________ ________: a series of non overlapping, three-nucleotide words.

triplet code

As RNA polymerase moves along the DNA, it ____________ the double helix, 10 to 20 bases at a time.

untwists

Promoters signal the transcriptional start point and usually extend several dozen nucleotide pairs ______________ of the start point.

upstream

Flexible pairing at the third base of a codon is called ___________ and allows some tRNAs to bind to more than one codon.

wobble