DNA Replication and Protein Synthesis Review
1. Compare the nitrogen bases that are found in a DNA nucleotide to those found in an RNA
nucleotide.
1.
2.
3.
4.
DNA( double stranded)
Adenine
Guanine
Cytocine
Thymine
1.
2.
3.
4.
RNA (single stranded)
Adenine
Guanine
Cytocine
Uracil
2. What nitrogen base bonds with the nitrogen bases found in DNA:
 Adenine - _Thymine________
 Guanine - _Cytocine________
 Thymine - _Adenine________
 Cytosine- _Guanine________
3. What nitrogen base bonds with the nitrogen bases found in RNA:
 Adenine - _Uracil________
 Guanine - _Cytocine________
 Uracil - __Adenine_______
 Cytosine- _Guanine________
4. In the Figure below, use the letter P to label all of the phosphate groups. Use an S to label
all the sugar molecules. For labeling the nitrogen bases, use a T for thymine and a C for
cytosine. Guanine and A for adenine. Circle and label a triplet. Circle and label a monomer of
DNA called the nucleotide. How many nucleotides are there in the DNA stand below?
___8_____. What is the ratio of guanine to Cytosine? _1:1_ Adenine to Thiamine? _1:1_
Nucleotide
Phosphate
Group
C
Sugar Group
Codon (triplet)
T
5. What is the above process called?
Replication
6. Why is this process important?
DNA must be copied so it can be sent out of the nucleus
7.
Label the molecule or organelle that is Roman numerated in the illustration above. What
process during protein synthesis is occurring in the illustration? At what organelle does this
occur?
I
II
III
IV
V
Process
organelle
anticodon
mRNA
Amino Acid Chain
tRNA
Amino Acid
Translation
Ribosome
8. If all organisms DNA are made up of the same four nucleotides, what makes one species
different from the other?
The arrangement of codons (nitrogen bases).
9. A nitrogen base sequence for a segment of DNA is ATATCCCGCTAC. What would be the
complementary strand to this segment of DNA? What amino acids does this segment code
for? Remember, you have to transcribe to mRNA first. What would happen if there was a
change (mistake) in the DNA segment where AGA was changed to ATT during protein
synthesis?
DNA: TATAGGGCGATG
RNA: AUAUCCCGCUAC
Amino Acids: Isoleucine, Serine, Arginine, Tyrosine
10. What would the original DNA segment be if the tRNA segment or anticodons were
UUUUAGGCCCGUA?
mRNA:
DNA:
AAAAUCCGGGCAU
TTTTAGGCCCGTA
11. What would the original DNA segment be if the mRNA segment or codons were
UUUUAGGCCCGUA?
AAAATCCGGGCAT
12. Where does transcription occur? What molecule is created? Why can DNA not leave the
nucleus?
Nucleus, mRNA
13. If DNA, tRNA and mRNA were positions held at a factory, what positions would they hold
and what would be their job description?



DNA –
mRNA tRNA -