Topic 1 | The relationship between nucleic acids and proteins WORKSHEET 1.4 Name: .......................................................................................................... Class: ............................... Date: .................................... Comparing DNA and RNA 1. Name the monomer of nucleic acids. ........................................................................................................................................................................................................ 2. Label the diagram shown. 3. Complete the table given below to show differences between DNA and RNA. DNA Number of strands Sugar Nitrogenous bases Location © John Wiley & Sons Australia, Ltd RNA Topic 1 | The relationship between nucleic acids and proteins 4. a. Label the diagram shown. b. Which DNA feature is shown in the diagram in part a? ................................................................................................................................................................................................ c. Identify the biomolecules shown below and label the parts. .................................................................... .................................................................... © John Wiley & Sons Australia, Ltd Topic 1 | The relationship between nucleic acids and proteins 5. List and describe the functions of the types of RNA. ........................................................................................................................................................................................................ ........................................................................................................................................................................................................ ........................................................................................................................................................................................................ ........................................................................................................................................................................................................ ........................................................................................................................................................................................................ ........................................................................................................................................................................................................ ........................................................................................................................................................................................................ ........................................................................................................................................................................................................ ........................................................................................................................................................................................................ 6. The structures of the various nitrogenous bases in DNA and RNA are shown below. a. Write the chemical formula for each molecule. The first one has been done for you. Uracil: C4H4N2O2 Cytosine: ................................................. Thymine: ................................................. Adenine: .................................................. Guanine: .................................................. © John Wiley & Sons Australia, Ltd Topic 1 | The relationship between nucleic acids and proteins b. With reference to the structure shown explain why: i. guanine is complementary to cytosine and not adenine in a DNA molecule ........................................................................................................................................................................................ ........................................................................................................................................................................................ ........................................................................................................................................................................................ ........................................................................................................................................................................................ ........................................................................................................................................................................................ ii. adenine can pair with uracil and thymine, but not with cytosine ........................................................................................................................................................................................ ........................................................................................................................................................................................ c. Nitrous acid is a mutagenic agent that can affect DNA bases. One effect of nitrous acid can be on cytosine. It can cause deamination on cytosine, causing the NH2 group to be replaced with an oxygen group (O). Explain the effect this may have on a DNA sequence. ................................................................................................................................................................................................ ................................................................................................................................................................................................ ................................................................................................................................................................................................ ................................................................................................................................................................................................ © John Wiley & Sons Australia, Ltd
