1. The basic building blocks of DNA are Amino acids Glucose Nucleotides fructose

2. Each DNA nucleotide is composed of three parts 2. Each DNA nucleotide is composed of three parts. Identify which of the following is NOT part of a DNA nucleotide. A glucose sugar A phosphate group A nitrogen base Deoxyribose sugar

3. Adenine, Cytosine, Guanine and Thymine are the four possible __________ for a DNA nucleotide. pentose (five carbon) sugars phosphate groups nitrogenous bases

4. The nucleotides in a DNA molecule are arranged in a double strand with bonds between _______________ forming the “rungs” that connect the two strands. pairs of nitrogenous bases pairs of sugars pairs of phosphate groups a sugar molecule and a phosphate group

5. The bonds between the pair of nitrogenous bases are stronger covalent bond that keeps the two strand permanently attached weaker hydrogen bonds that allow the two strands to be separated ionic bonds that allow a transfer of current along the molecule

The two strands are separated when DNA is replicated, as well as when mRNA copies are made for protein synthesis.

6. Which of the following is a correct about how the nitrogenous base adenine pairs in a DNA molecule. Adenine always pairs with Cytosine Thymine Guanine Deoxyribose

Adenine with Thymine Cytosine with Guanine

7. If one strand of a DNA molecule is ACATGG, the other strand will be CTCGAA TGTACC GTGCAA ACATGG

8. If the nitrogenous bases in the DNA of a species of monkey is 21% adenine, what would be the percentage of nitrogenous bases that are guanine? 58% 42% 29% 21% 10.5%

A = T If 21% A, also 21% T. This is 42 % of the nitrogenous bases for this species. 58% = C + G Since C = G, 29% G

9. DNA must be accurately replicated each time the cell is preparing to divide so that each daughter cell has an identical copy of all of the genetic information. What characteristic of the DNA’s structure is most important in allowing it to be accurately copied. The shape of the deoxyribose sugar The complementary pairing of nitrogenous bases in the “rungs” The sugar-phosphate backbone The shape of the phosphate

The two strands of the DNA molecule are separated as it is being replicated. Each strand serves as a template for the new strand. Since A always is paired with T and C always paired with G, it can be accurately replicated.

10. Which enzyme unwinds the DNA and separates the two strands during DNA replication? Helicase DNA polymerase RNA polymerase Catalase

Helicase unwinds the DNA double helix

11. The role of the enzyme DNA polymerase is to Unwind the DNA double helix Add complementary nucleotides Repair the sugar-phosphate backbone Break the hydrogen bonds between nucleotides

DNA Polymerase (III) is the enzyme that synthesizes the new DNA molecule by adding complementary nucleotides. Complementary nucleotides means that a nucleotide with the nitrogenous base adenine on the parent strand is paired with a nucleotide with the nitrogenous base thymine(and vice versa). Likewise cytosine nucleotides are paired with guanine nucleotides . To remember the role of DNA polymerase, recall that a polymer means a chain of building block pieces. DNA is a polymer of nucleotides. So the role of DNA polymerase is to build the DNA polymer by adding nucleotides.

12. Each gene is the information to build one protein (or polypeptide chain in a protein). What are the two steps in producing the protein? Replication and Transcription Replications and Translation Transcription and Translation Transcription and Mutation Translation and Mutation

13. The purpose of transcription is to Produce an mRNA copy of a gene Produce tRNA’s Add the correct amino acids to produce a protein Assembly the rRNA into the ribosomal subunits

14. The purpose of translation is to Produce an mRNA copy of the gene Produce tRNA’s Add the correct amino acids to produce a protein Assembly the rRNA into the ribosomal subunits

15. Which of the following is NOT a correct difference between DNA and RNA DNA is composed of 2 strands, RNA is a single strand DNA is a chain of nucleotides, RNA is a chain of amino acids DNA uses the nitrogen base thymine, RNA uses the nitrogen base uracil DNA uses the sugar deoxyribose, RNA uses the sugar ribose

Both DNA and RNA are chains of nucleotides, which have a sugar, a phosphate group and a nitrogenous base. Sugar is ribose for RNA , deoxyribose for DNA Uracil is used in place of Thymine as nitrogenous base that pairs with Adenine DNA is a double helix (2 strands), while RNA is a single-stranded copy.

16. If the DNA sequence for a gene being transcribed is ATGCTA, the mRNA that is produced will have the sequence TACGAT AUCGUA UACGAU UAGCUA TAGCAT ATCGTA

C A B 15. B 16. C