02:53Lipids | Fats, Steroids, and Phospholipids | Biological Molecules Simplified #42 Minute Classroom993views
Multiple ChoiceWhich of the following is a true statement comparing phospholipids and triacylglycerols (fats and oils)? 1604views
Multiple ChoiceLipids differ from other large biological molecules in that they __________. 1123views
Multiple ChoiceWhich of the following terms can be correctly used to describe compounds that do not mix with water? 737views
Multiple ChoiceNutritionally, saturated triacylglycerols are considered to be less healthful than unsaturated triacylglycerols. What is the difference between them? 1586views
Multiple ChoiceThe lipids that form the main structural component of cell membranes are __________. 1276views
Multiple ChoiceIf a small droplet of triacylglycerol molecules is suspended in water, the fat molecules form a "ball of spaghetti" with no particular orientation. But if a droplet of phospholipid molecules is put in water, all the molecules point outward, toward the water. Phospholipids are forced into this orientation because phospholipids have __________. 943views
Multiple ChoiceThe sex hormones estradiol and testosterone belong to which class of molecules? 2184views
Multiple ChoiceHigh cholesterol levels are considered a major risk factor for heart disease. If it is so bad for humans, why does the body make cholesterol in the first place? 1601views2rank
Multiple ChoiceManufacturers make vegetable oils solid or semisolid at room temperature by __________. 1422views
Multiple ChoiceSome lipids are formed when fatty acids are linked to glycerol. These subunits are linked together by __________. 1386views1rank
Multiple ChoiceThe fatty acid tails of a phospholipid are __________ because they __________. 1233views6rank
Textbook QuestionHow do the phospholipids in archaea differ from those in other cells? a. They have tails made of unsaturated fatty acids instead of saturated fatty acids. b. They do not contain hydrocarbon chains. c. They have isoprenoid tails instead of fatty acid tails. d. They have two hydrocarbon chains instead of three hydrocarbon chains.846views
Textbook QuestionMacronutrients . a. include carbohydrates and vitamins; b. should make up a small percentage of a healthful diet; c. are essential in minute amounts to help enzymes function; d. include carbohydrates, fats, and proteins; e. are synthesized by cells and not necessary to obtain from the diet965views
Textbook QuestionWhich of the following is true of unsaturated fats? a. They are more common in animals than in plants. b. They have double bonds in their fatty acid chains. c. They generally solidify at room temperature. d. They contain more hydrogen than do saturated fats having the same number of carbon atoms.3175views
Textbook QuestionWhat makes a fatty acid an acid? a. It does not dissolve in water. b. It is capable of bonding with other molecules to form a fat. c. It has a carboxyl group that can donate an H+ to a solution. d. It contains only two oxygen atoms.1233views
Textbook QuestionCooking oil lipids consist of long, unsaturated hydrocarbon chains. Would you expect these molecules to form membranes spontaneously? Why or why not? Describe, on a molecular level, how you would expect these lipids to behave in water.1045views
Textbook QuestionWhich of the following terms is least like the others? a. monosaccharide; b. phospholipid; c. fat; d. steroid; e. lipid699views
Textbook QuestionThe main constituents of the plasma membrane are . a. carbohydrates and lipids; b. proteins and phospholipids; c. fats and carbohydrates; d. fatty acids and nucleic acids1643views
Textbook QuestionUnsaturated fats a. have double bonds in their fatty acid chains. b. have fewer fatty acid molecules per fat molecule. c. are associated with greater health risks than are saturated fats. d. are more common in animals than in plants.1361views
Textbook QuestionWhich of the following substances is a major component of the cell membrane of a fungus? a. cellulose b. chitin c. cholesterol d. phospholipids902views
Textbook QuestionA fat molecule consists of . a. carbohydrates and proteins; b. complex carbohydrates only; c. saturated oxygen atoms; d. a carbon skeleton and fatty acids1250views
Textbook QuestionAnother aspect of the Nurses' Health Study looked at the percentage of change in the risk of coronary heart disease associated with substituting one dietary component for another. These results estimated that replacement of 5% of energy from saturated fat in the diet with unsaturated fats would reduce the risk of heart disease by 42%, and that the replacement of 2% of energy from trans fat with unsaturated fats would reduce the risk by 53%. Explain what these numbers mean.641views
Textbook QuestionMark the following statements as true or false. If a statement is false, correct it to make a true statement.c. Lipids contain oxygen and are therefore polar covalent compounds.216views
Textbook QuestionConsidering that water is a main component of the juices in the stomach and intestines, explain why digestion of lipids is more complicated than digestion of carbohydrates and proteins.216views
Textbook QuestionExplain why monosaccharides are polar and fatty acids are nonpolar even though they both contain the same atoms.281views