Part A This animation illustrates the functioning of a _____ protein. To view the animation, click here. Then click on the image to start the animation. receptor contractile structural protein gene regulatory transport Correct The protein is transporting a substance across the cell membrane. Part B Arrow A is indicating a(n) _____ protein. transport enzyme signal structural receptor Correct… Read More »

Part A Which molecule is not a carbohydrate? Starch Glycogen Lipid Cellulose Correct A lipid is a hydrophobic polymer, not a carbohydrate. Part B Which of the following statements about monosaccharide structure is true? Aldoses and ketoses differ in the position of their hydroxyl groups. A six-carbon sugar is called a pentose. All monosaccharides contain carbon, hydrogen, oxygen, and nitrogen… Read More »

Part A Which of these is NOT a lipid? wax cholesterol phospholipid RNA steroids Correct RNA is a nucleic acid Part B This figure is an example of a(n) _____. nucleic acid saturated fat unsaturated fat steroid protein Correct The fatty acid tails lack double bonds. Part C Which of these is a phospholipid? Answer Correct Phospholipids are… Read More »

Part A Proteins are polymers of _____. glycerol nucleotides amino acids hydrocarbons CH2O units Correct Proteins are polymers of amino acids. Part B What type of bond joins the monomers in a protein’s primary structure? ionic hydrophobic hydrogen peptide S – S Correct The amino acids of a protein are linked by peptide bonds. Part C Which of… Read More »

Part A If a strand of DNA has the nitrogen base sequence 5′-ATTTGC-3′, what will be the sequence of the matching strand? 3′-GCAAAT-5′ 3′-ATTTGC-5′ 3′-UAAACG-5′ 3′-TUUUCG-5′ 3′-TAAACG-5′ Correct Adenine pairs with thymine and guanine pairs with cytosine. Part B If a DNA double helix is 100 nucleotide pairs long and contains 25 adenine bases, how many guanine bases… Read More »

Condensation and Hydrolysis Reactions Part A Which polymers are composed of amino acids? Monomers Carbohydrates Proteins Nucleic acids Correct Proteins are composed of amino acids joined together. Part B Which of the following is not attached to the central carbon atom in an amino acid? A side chain (“R group”) An oxygen A carboxyl functional group An amino functional group… Read More »

Functional Groups Part A Which one of these is an amino group? B D E A C Correct This is an amino group, NH2. Part B Which of these is a phosphate group? F A C E B Correct Of the choices, this is the only one that contains phosphorus. Part C Which of these is a hydroxyl… Read More »

Isomers Part A L-dopa is used to treat _____. muscle sprains laryngitis Marfan’s syndrome Parkinson’s disease Alzheimer’s disease Correct People with Parkinson’s disease lack dopamine. Part B What kind of effect does R-dopa have on Parkinson’s disease? It alleviates the symptoms. It makes the symptoms of Parkinson’s disease worse. At first it makes the symptoms worse but over… Read More »

Diversity of Carbon-Based Molecules Part A How do these hydrocarbons differ? One of these hydrocarbons is longer than the other. One of these hydrocarbons has a ring structure. These hydrocarbons are identical. One of these hydrocarbons is branched. One of these hydrocarbons has a double bond. Correct The hydrocarbon on the right is longer than the hydrocarbon on… Read More »

Ocean Acidification Part A What is the main reason that the oceans are becoming more acidic? the dumping of garbage and sewage into the oceans absorption by the oceans of carbon dioxide generated by burning fossil fuels large crude oil spills in the oceans fertilizer runoff in major rivers flowing into the oceans Correct Part B How much… Read More »