A Hydrocarbon Is Hydrophobic
Question: Saturated fatty acids and unsaturated fatty acids differ in: A. the number of carbon-to-carbon bondsB. the consistency at room temperatureC. the number of hydrogen atoms presentD. all of the choices are differences between saturated and unsaturated fatty acid
Answer: D. all of the choices are differences between saturated and unsaturated fatty acid
Question: Which of the following would NOT be a molecule used for energy storage? A. starchB. triglycerideC. glycogenD. chitin
Answer: D. chitin
Question: The lipids of the cell membrane and the lipids found in butter and vegetable oil differ in which of the following? A. the number of fatty acids attached to the glycerol moleculeB. the glycerol moleculeC. the carbon to carbon bondsD. lipids of the cell membrane do not have hydrophobic sections of the molecule
Answer: A. the number of fatty acids attached to the glycerol molecule
Question: Which of the following is NOT one of the four most common elements found in living organisms? A. hydrogenB. oxygenC. carbonD. sulfurE. nitrogen
Answer: D. sulfur
Question: Organic molecules are those that contain at least A. carbon.B. carbon and oxygen.C. carbon and hydrogen.D. carbon, oxygen, and hydrogen.
Answer: C. carbon and hydrogen.
Question: The differences between organic and inorganic molecules do not follow simple absolute rules. However, most organic molecules are associated with living organisms. Which of the following statements does NOT correspond to the general distinctions between these types of molecules? A. Carbon dioxide (CO2) lacks hydrogen atoms found in organic molecules.B. Formaldehyde (CH2O) is a small molecule compared to most organic molecules.C. Salt (Na+Cl-) is not an organic molecule but is important to the life of many organisms.D. Because they are in living organisms, organic carbon atoms are different from the inorganic carbon atoms forming the molecular structure of soot or a diamond.
Answer: D. Because they are in living organisms, organic carbon atoms are different from the inorganic carbon atoms forming the molecular structure of soot or a diamond.
Question: A hydrocarbon is hydrophobic A. at all times.B. only in the living cell environment.C. except when it has an attached ionized functional group.D. in carbohydrates but not in lipids.
Answer: C. except when it has an attached ionized functional group.
Question: What term is used for molecules that have identical molecular formulas but the atoms in each molecule are arranged differently? A. isotopeB. isomerC. homomoleculesD. organicE. balanced
Answer: B. isomer
Question: Identify the following molecule as a:http://www.flickr.com/photos/60296733@N06/5519768367/A. amino acidB. hydrocarbonC. carbohydrateD. alcoholE. cholesterol
Answer: E. cholesterol
Question: Glucose (C6H12O6) can exist as both an open-chain form and a closed-ring form. Before 1900, glucose was only thought to occur as an open chain. Now we know that over 99 percent of the time, glucose occurs in the closed-ring form. What possible difference between these forms would give chemists a clue that the open-chain form was not present? A. Open-chain molecules can form polymers and glucose does not.B. Only open-chain forms can undergo condensation, which does not occur with glucose.C. An open chain presents ends with functional groups (in this case aldehyde), and glucose failed to undergo typical aldehyde reactions; a phenomenon that could be explained by having no end functional group in a ring structure.D. Because glucose is solid at room temperature, it must have saturated hydrocarbon chains.E. Glucose could not be "denatured" so it must be a tight chain.
Answer: C. An open chain presents ends with functional groups (in this case aldehyde), and glucose failed to undergo typical aldehyde reactions; a phenomenon that could be explained by having no end functional group in a ring structure.
Question: What is the molecular formula for 5 glucose molecules? A. Cᵥ30Hᵥ50Oᵥ25B. Cᵥ30Hᵥ60Oᵥ30C. Cᵥ30Hᵥ52Oᵥ26D. Cᵥ6Hᵥ24Oᵥ12
Answer: A. Cᵥ30Hᵥ50Oᵥ25
Question: A polysaccharide is a polymer made up of which kind of monomers? A. simple sugarsB. amino acidsC. nucleotidesD. alternating sugar and phosphate groupsE. fatty acids and glycerol
Answer: A. simple sugars
Question: A lipid is a polymer made up of which kind of monomers? A. glucose or modified glucose moleculesB. amino acidsC. nucleotidesD. alternating sugar and phosphate groupsE. fatty acids and glycerol
Answer: E. fatty acids and glycerol
Question: A dehydration reaction can also be called a _________ reaction since it forms water. A. a condensationB. a hydrolysisC. an isomericD. an energy-releasingE. monomer formation
Answer: A. a condensation
Question: Which pair are both structural carbohydrate molecules? A. starch and glycogenB. starch and celluloseC. glycogen and celluloseD. cellulose and chitinE. glycogen and chitin
Answer: D. cellulose and chitin
Question: Which carbohydrate is found in the cell walls of plants? A. starchB. chitinC. celluloseD. glycogenE. glycerol
Answer: C. cellulose
Question: Which carbohydrate is used in the liver for energy storage? A. starchB. chitinC. celluloseD. glycogenE. glycerol
Answer: D. glycogen
Question: Which carbohydrate is found in the exoskeleton of insects and crabs? A. starchB. chitinC. celluloseD. glycogenE. glycerol
Answer: B. chitin
Question: Identify this molecule as a:http://www.flickr.com/photos/60296733@N06/5519768389/A. amino acidB. hydrocarbonC. carbohydrateD. alcohol E. lipid
Answer: C. carbohydrate
Question: If an animal needed to store energy for long-term use, but not be encumbered with the weight of extra tissue, which is the best molecule for storage? A. fructose and glucose in the form of honeyB. high-calorie fat moleculesC. complex cellulose moleculesD. starchE. glycogen with extensive side branches of glucose
Answer: B. high-calorie fat molecules
Question: A peptide bond is found in which type of biological molecule? A. carbohydrateB. lipidC. nucleic acidD. protein
Answer: D. protein
Question: The alpha helix and beta sheet are found at which level of protein organization? A. primary structureB. secondary structureC. tertiary structureD. quaternary structure
Answer: B. secondary structure
Question: After eating eggs for breakfast, you return in the evening, dunk the dirty dishes in water, and notice the yellow streaks remain "dried on." However, after soaking awhile, the complex of various egg yolk molecules easily "washes off." What has happened? A. Heating denatured the egg protein molecules, hydrolysis reactions then formed bonds in the dried egg, and soaking in water eventually resulted in condensation reactions where water broke these bonds.B. Heating denatured the egg protein molecules, unorganized condensation reactions then formed bonds in the drying egg, and soaking in water eventually resulted in hydrolysis reactions where water broke these bonds.C. The egg monomers were fused to become one polymer, which was easily dissolved by water back into monomers.D. The presence or absence of water changes the molecules from hydrophilic to hydrophobic respectively.E. The addition of water converted organic molecules into inorganic molecules.
Answer: B. Heating denatured the egg protein molecules, unorganized condensation reactions then formed bonds in the drying egg, and soaking in water eventually resulted in hydrolysis reactions where water broke these bonds.
Question: Below freezing and above boiling, cells are unable to function as "liquid machinery." However, most organisms' cells are still limited from functioning throughout this full range of liquid temperatures. At the molecular level in different organisms, cells' ability to vary in their tolerance to temperature, etc., is most closely related to variation in A. enzyme activity and protein denaturation.B. ATP efficiency.C. ability to form glucose polymers.D. replication of nucleic acids.E. extent of saturation of fatty acids.
Answer: A. enzyme activity and protein denaturation.
Question: Which of these statements is NOT true about DNA? A. It is the genetic material of the cell.B. It forms a double helix.C. Adenine pairs with thymine and guanine pairs with cytosine.D. It contains the sugar ribose.E. The sugar and phosphate groups form the backbone of the molecule.
Answer: D. It contains the sugar ribose.
Question: Fish sperm consists mostly of the male fish's DNA. If we tested a sample chemically, we should find relatively high amounts of A. nitrogenous bases, sugar, and phosphate groups.B. phospholipids and steroids.C. amino acids and unsaturated fats.D. triglycerides and ATP.E. globular proteins and stored fats.
Answer: A. nitrogenous bases, sugar, and phosphate groups.
Question: Which statement is true about RNA? A. It contains adenine paired to thymine.B. One of the bases from DNA is replaced by uracil.C. It contains the sugar deoxyribose.D. Its nucleotides contain twice as many phosphate groups as DNA's nucleotides.E. It is a double-stranded molecule.
Answer: B. One of the bases from DNA is replaced by uracil.
Question: The reactivity of an organic molecule is primarily dependent upon ____________ of the molecule. A. the carbon skeletonB. the attached functional groups such as an hydroxyl groupC. the isomerD. All of the choices are correct.
Answer: B. the attached functional groups such as an hydroxyl group
Question: Which Figure is of an unsaturated fat?http://www.flickr.com/photos/60296733@N06/5520358314/ A. Figure AB. Figure B
Answer: A. Figure A
Question: A saturated fat is A. solid at room temperature.B. has fatty acids with no double bonds between the carbon atoms.C. is of animal origin.D. All of the choices are correct.
Answer: D. All of the choices are correct.
Question: A polypeptice has an amino acid sequence of: alanine-leucine-tryptophane-glycien-valine-alanine This chain of amino acids is further organized into a helix that in-turn, folds in and around itself to form a globular structure. The primary structure of this polypeptide is: A. globularB. pleated-sheetC. alpha helixD. alanine-leucine-tryptophane-glycien-valine-alanine
Answer: D. alanine-leucine-tryptophane-glycien-valine-alanine
Question: How many molecules of water are used to degrade this polypeptide, using hydrolysis reactions, into its constituent amino acids? alanine-leucine-tryptophane-glycine-valine-alanine A. sixB. fiveC. oneD. seven
Answer: B. five
Question: Choose the Figure that depicts polymer synthesis.http://www.flickr.com/photos/60296733@N06/5519768471/ A. Figure 1B. Figure 2
Answer: A. Figure 1
Question: If a segment of DNA has 20% adenine in its base composition, what percent thymine is there? A. 20%B. 80%C. 60%D. 30%
Answer: A. 20%
Question: Carbon can form covalent bonds with as many as four other atoms. True False
Answer: TRUE
Question: Waxes consist of a glycerol bonded to three long-chain fatty acids. True False
Answer: FALSE
Question: ATP is a protein that supplies energy to the cell. True False
Answer: FALSE
Question: Starch is a protein that serves in energy storage in plant cells. True False
Answer: FALSE
Question: Migratory birds store energy as glycogen which is lighter than fat. True False
Answer: FALSE