12.3 RNA and Protein Synthesis
A. A ___________ is a segment of ___________ that has the code
for a certain ___________
· Many proteins are enzymes, which catalyze and regulate
chemical reactions.
· Proteins are each specifically designed to build or operate a
component of a living cell.
B. For a gene to work, the genetic instructions in that segment
of DNA must be ________________
· The first step is to copy the DNA sequence into
________________
· RNA is a molecule which contains instructions for making
________________
C. RNA is similar to DNA, except for three differences:
· The sugar in RNA is________________instead of deoxyribose
· RNA is ________________________________
· RNA has ________________ in place of ________________
Questions?
What 4 nitrogen bases are found in RNA?
DNA molecules are double stranded and RNA molecules are
_________________ stranded.
D. RNA is copied from DNA in a process called
________________where:
· The enzyme _______________________binds to DNA and separates
the two DNA strands
· RNA Polymerase builds a complementary strand of RNA using one
strand of DNA _________________________
· The DNA is transcribed into RNA following base-pairing rules
except that ________________ binds to ________________
E. There are ________________ main kinds of RNA:
· _______________________has the instructions for joining amino
acids into a chain to make a protein
· _______________________ Proteins are assembled on ribosomes,
which are made up of proteins and rRNA
· ________________________during protein construction it
transfers each amino acid to the ribosome carries each amino acid
to the ribosome according to the coded message in mRNA each tRNA
carries only one kind of amino acid the three bases are called the
anticodon, and match up with a codon
F. The directions for making proteins are found in the order of
the four bases – A, U, C, G
· The genetic code is read three letters at a time, called a
________________
· Each codon, or group of ________________ nucleotides, stands
for a particular ______________
·
__________________________________________________________________________________________
· Some amino acids are specified by
________________________________codon
· ________________ codon is a start signal for translation
· There are ________________________________that can signal the
end of a protein
Questions?
Put a line separating each codon.A U G C G A U A C G A U U G
A
Give an example of an amino acid that is specified by more than
one codon.
What codon is the start codon?
List the stop codons
G. Translation is the process in which the cell uses information
from mRNA to make ________________
· Translation takes place on ________________
· mRNA is transcribed from DNA in the ________________
· The mRNA moves into the cytoplasm and attaches to a
________________
· As each codon of the mRNA moves through the ribosome, the
proper amino acid is brought into the ribosome by
________________
· The ribosome joins together each ________________ in this way
the chain grows
· When the ribosome reaches a ________________, it releases the
newly formed protein and the process of translation is complete
Question?
Translate the following mRNA sequence:
A U G A A C G C C C C A U A G
Which of the following identifies the process shown at point
Y?
a. Translation
b. Translocation
c. Replication
d. Transcription
Which of the following identifies the process shown at point
Z?
a. Translation
b. Translocation
c. Replication
d. Transcription
