AP Questions

A student analyzed a viral genome and found that the genome had the following nucleotide composition. • 28% adenine • 20% thymine • 35% cytosine • 17% guanine Which of the following best describes the structure of the viral genome? Double-stranded DNA A Single-stranded DNA B Double-stranded RNA C Single-stranded RNA D

B

Which of the following best describes the structures of carbohydrates? They only occur as disaccharides. A They occur as monomers, chains of monomers, and branched structures. B They only occur as long and branched structures. C They occur as chains of monomers that hydrogen bond with complementary chains of monomers. D

B

Which of the following characteristics of Figure 1 best shows that the fragment is RNA and not DNA? The 5′ to 3′ orientation of the nucleotide chain A The identity of each nitrogenous base B The charges on the phosphate groups C The type of bond linking the nucleotides together D

B

Which of the following statements best describes how organisms such as rabbits obtain the carbon necessary for building biological molecules? Rabbits eat plants and use energy absorbed from the plants to make carbon atoms from electrons, protons, and neutrons in the air. A Rabbits eat plants and break down plant molecules to obtain carbon and other atoms that they rearrange into new carbon-containing molecules. B Rabbits eat plants and use water absorbed from the plants to hydrolyze CO2, which the rabbits breathe in from the air and use as a carbon source. C Rabbits eat plants and make carbon-containing molecules by using carbon atoms that the plants absorbed from the soil and stored in the cells of their leaves. D

B

Bacteriophages are viruses that infect bacteria. In an experiment, bacteriophages were labeled with either radioactive phosphorus or radioactive sulfur. The labeled bacteriophages were incubated with bacteria for a brief amount of time and then removed. The infected bacteria cells were found to contain significant amounts of radioactive phosphorus but not radioactive sulfur. Based on the results of the experiment, which of the following types of molecules did the bacteriophages most likely inject into the bacteria cells? Simple carbohydrate A Amino acid B DNA C Polypeptide D

C

Based on the molecular structures shown in the figure, which molecule is likely to be solid at room temperature? Linoleic acid, because the absence of carbon-carbon double bonds allows the molecules to pack closely together. A Linoleic acid, because the presence of carbon-carbon double bonds prevents the molecules from packing closely together. B Palmitic acid, because the absence of carbon-carbon double bonds allows the molecules to pack closely together. C Palmitic acid, because the presence of carbon-carbon double bonds prevents the molecules from packing closely together. D

C

This group of questions refers to the following groups of biological compounds. (A) Proteins (B) Carbohydrates (C) Nucleic acids (D) Lipids (E) Steroids Used to carry the genetic code Proteins A Carbohydrates B Nucleic acids C Lipids D Steroids

C

The CFTR protein is made up of 1,480 amino acids linked together in a chain. Some humans produce a version of the CFTR protein in which phenylalanine (an amino acid) has been deleted from position 508 of the amino acid chain. Which of the following best predicts how the amino acid deletion will affect the structure of the CFTR protein? It will have no observable effect on the structure of the CFTR protein. A It will affect the primary structure of the CFTR protein, but the other levels of protein structure will not be affected. B It will affect the secondary and tertiary structures of the CFTR protein, but the primary structure will not be affected. C It will affect the primary, secondary, and tertiary structures of the CFTR protein. D

D

Which of the following conclusions is most clearly supported by the representations of nucleic acid #1 and nucleic acid #2 ? Nucleic acid #1 contains only purines, whereas nucleic acid #2 contains only pyrimidines. A Nucleic acid #1 contains the sugar ribose, whereas nucleic acid #2 contains the sugar deoxyribose. B Nucleic acid #1 contains positively charged phosphate groups, whereas nucleic acid #2 does not. C Nucleic acid #1 contains adenine-thymine base pairs, whereas nucleic acid #2 does not. D

D

Which of the following is an accurate description of the process shown in Figure 1 ? The linking of amino acids with an ionic bond as an initial step in the protein synthesis process A The formation of a more complex carbohydrate with the covalent bonding of two simple sugars B The hydrolysis of amino acids with the breaking of covalent bonds with the release of water C The formation of a covalent peptide bond in a dehydration synthesis reaction D

D