Download Biology: DNA Unit Review

Name_________________________________________________________Date_____________________Period_________
Biology: DNA Unit Review
DNA Basic Information
1. How many nucleotides are shown in the DNA segment pictured?
2. Circle an entire nucleotide on the DNA segment.
3. Name the three parts of a DNA nucleotide.
a. ____________________________
b. ____________________________
c. ____________________________
4. Use the letters P (phosphate) and S (sugar) to label the sugar
and phosphate of the DNA molecule to the right.
5. Which part does the phosphate molecule connect with?
6. What is the special shape of DNA called?
7. a ) Which type of chemical bond joins the DNA nitrogen bases? b ) Which type of chemical bond joins the
backbone of the DNA molecule?
a._________________________________
DNA Replication
8. The diagram below shows DNA replication.
a. In area A, fill in the missing DNA bases from
the given nucleotides.
b. Name the enzyme that will separate the DNA
strands in area A.
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c. In area B, perform DNA replication and fill in
the two new strands of DNA.
d. Name the enzyme that will reconnect the DNA
bases in area B.
e. After filling in the correct DNA bases in area B,
are the two strands of DNA identical?
YES
NO
b._________________________________
9. Put the pictures of DNA replication in order by placing a 1, 2, or 3 on the line above the picture.
10. Describe what is happening on the lines below the picture.
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DNA and RNA Comparison
11. Complete the following chart by comparing DNA, mRNA, and tRNA. Sample answers have been provided.
DNA
mRNA
tRNA
Molecule full name
Deoxyribonucleic acid
Name of Sugar
Ribose
Adenine (A), Uracil (U),
Guanine (G), Cytosine (C)
Nitrogen bases present
Function
Stores genetic
information.
12. For each statement write DNA, mRNA, or tRNA
________Holds the original coded
information for making proteins
________Can replicate itself (with the help of
enzymes)
________Copies DNA’s coded message
________Found in the nucleus only
________Found mostly in the cytoplasm
________Found equally in both the cytoplasm
and nucleus
________Carries coded message to the ribosome
________Carries amino acids to the ribosome for
assembly
Transcription
13. Pretend RNA polymerase has already separated the DNA strand below. Perform transcription and fill in
the mRNA bases from the given DNA bases. Remember to replace T with U for RNA.
14. Following the rules of transcription, predict which DNA bases would have created the given mRNA bases.
Remember that DNA has different bases than RNA.
15. Following the rules of transcription, fill in the missing bases from the strands of DNA and RNA.
16. Examine #15. Is the top strand a segment of DNA or RNA? Explain your answer.
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Transcription and Translation: Use the picture to answer questions 17-19.
17. Describe what is forming and happening in area A of the diagram (use best writing skills).
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18. Describe what is forming and happening in area B of the diagram (use best writing skills).
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19. Describe what is being assembled and happening in area C of the diagram (use best writing skills).
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20. Which mRNA codon will start the process of translation?________________________________________
21. Which amino acid does every protein begin with?______________________________________________
22. Which mRNA codons will end the process of translation?________________________________________
23. For each statement write either DNA helicase, DNA polymerase, or RNA polymerase
______________________
Reconnects DNA during replication
______________________
Separates DNA during transcription
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Separates DNA during replication
24. From the DNA information given, fill in the missing information.
DNA
mRNA
For #24-26, remember
that mRNA=CODONS
that code for the
amino acid.
tRNA
Amino acid
tRNA
Amino acid
TTT
25. From the tRNA information given, fill in the missing information.
DNA
mRNA
GUU
26. From the amino acid given, fill in the missing information.
DNA
mRNA
tRNA
Amino acid
Methionine
27. Below is a strand of mRNA. Follow the rules
of translation and fill in the tRNA
(anticodons) strand below.
28. Which two amino acids does the following
DNA strand code for?