Protein Synthesis Nas 2 quiz 16
What happens to tRNA molecules after they add their amino acid to the growing protein chain? a) They are released from the mRNA to pick up the specific amino acid coded for by their anticodons. b) They degrade, and the RNA nucleotides are recycled. c) They pick up new amino acids, whichever one is closest in the cytoplasm.
a
Each codon of mRNA (hence each triplet in DNA) codes for one:
amino acid
The specific amino acid carried by a tRNA is determined it's:
anticodon
a set of three nucleotides on the tRNA that is complementary to an mRNA codon.
anticodon
RNA's to all the following except.... a) carry amino acids to ribosomes b) hold the cell together c) speed up cellular process d) switch cellular machinery on and off e) carry coded messages from the nucleus to the ribosome
b
the coded regions that are expressed sequences
extrons
Both the guanine cap (5') and a poly-A tail (3') help to......
protect strand from hydrolytic enzymes, attach to ribosome, and release RNA into cytoplasm
True or False? The same amino acid can be carried by different tRNA'S.
true
True or False? Whenever a cell needs to, it can unzip DNA and make a transcript of a sequence so that a protein can be made. DNA then zips up.
true
If a DNA sequence consists of 12 nucleotides, how many mRNA codons will there be?
4
What is the correct order of assembly in the cellular factory?
DNA - RNA - protein
The enzyme that creates mRNA from a DNA sequence is called:
RNA polymerase
What is transcription catalyzed by?
RNA polymerase
Which step comes first in protein synthesis?
Transcription
Which of the following best describes the process of translation? a) Anticodons on the mRNA molecule indicate the correct sequence of amino acids. b) Codons on the mRNA molecule are read by a ribosome. c) tRNA molecules bind to DNA in order to link amino acids in the correct order.
b
Ribosomes need mRNA and tRNA to help complete translation. Which statement correctly describes their roles? a) tRNA builds the ribosome, while mRNA translates the nucleus into a protein b) mRNA helps the tRNA translate the ribosome into a protein c) tRNA translates the code in the mRNA into a string of amino acids d) Ribosomes build tRNAs, which are translated into mRNA messages.
c
Which of the following descriptions of transcription is INCORRECT? a) Only certain genes (not the entire DNA strand) are transcribed at a given time. b) Only one strand of DNA is transcribed. c) The new mRNA strand elongates in the 3' to 5' direction.
c
a sequence of three nucleotides that codes for a specific amino acid.
codon
Translation is the second step of Protein Synthesis and it occurs in the:
cytoplasm
Where does the cell transcription take place in prokaryotes?
cytoplasm
True or False? When amino acids are brought in by tRNA, they are joined together by hydrolysis reactions to form the growing protein.
false
Name the three steps of transcription in order.
initiation, elongation, termination
noncoding regions of DNA or RNA
introns
Transcription is the first step of Protein Synthesis and it occurs in the:
nucleus
This RNA carry a protein building block (an amino acid) to a cell's protein assembly machine, called a ribosome. And translates the genetic code of messenger RNA (mRNA) into the amino acid sequence of proteins. What type of RNA is this?
tRNA
Which RNA carries amino acids to the ribosome during translation? mRNA (messenger RNA) rRNA (ribosomal RNA) tRNA (transfer RNA)
tRNA
_____________________ converts a gene into a single-stranded molecule.
transcription
What are the two steps of protein synthesis?
transcription and translation
________________________ converts an mRNA message into a polypeptide, or protein.
translation