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. __________________________________ 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.
_________________________________________________________________ _________________________________________________________________ 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).
_________________________________________________________________ _________________________________________________________________ _________________________________________________________________ 18. Describe what is forming and happening in area B of the diagram (use best writing skills).
_________________________________________________________________ _________________________________________________________________ _________________________________________________________________
19. Describe what is being assembled and happening in area C of the diagram (use best writing skills).
_________________________________________________________________ _________________________________________________________________ _________________________________________________________________ 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
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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?
