AP Bio Chapter 5

Which of the following statements concerning saturated fats is not true?

• They have multiple double bonds in the carbon chains of their fatty acids.
• They contain more hydrogen than unsaturated fats having the same number of carbon atoms.
• They generally solidify at room temperature.
• They are more common in animals than in plants.

Which of the following statements is true for the class of biological molecules known as lipids?

• They are made from glycerol, fatty acids, and phosphate.
• They are insoluble in water.
• They are made by dehydration reactions.
• They contain less energy than proteins and carbohydrates.

Upon chemical analysis, a particular polypeptide was found to contain 100 amino acids. How many peptide bonds are present in this protein?

• 99
• 97
• 98
• 101

If cells are grown in a medium containing radioactive ¹⁵N, which of these molecules will be labeled? (which has nitrogen in it?)

• both proteins and nucleic acids

• proteins only

• amylase only

• nucleic acids only

The label on a container of margarine lists "hydrogenated vegetable oil" as the major ingredient. What is the result of adding hydrogens to vegetable oil?

• The hydrogenated vegetable oil is less likely to clog arteries.
• The hydrogenated vegetable oil has more "kinks" in the fatty acid chains.
• The hydrogenated vegetable oil has fewer trans fatty acids.
• The hydrogenated vegetable oil stays solid at room temperature.

Which of the following is true of both starch and cellulose? 

• They are both structural components of the plant cell wall
• They are both polymers of glucose
• They are both used for energy storage in plants
• They can both be digested by humans

Lactose, a sugar in milk, is composed of one glucose molecule joined by a glycosidic linkage to one galactose molecule. How is lactose classified?

• As a disaccharide
• As a polysaccharide
• As a monosaccharide
• As a hexose

Which of the following best summarizes the relationship between dehydration reactions and hydrolysis?

• Dehydration reactions eliminate water from lipid membranes, and hydrolysis makes lipid membranes water permeable.
• Dehydration reactions ionize water molecules and add hydroxyl groups to polymers; hydrolysis reactions release hydroxyl groups from polymers.
• Dehydration reactions assemble polymers, and hydrolysis reactions break down polymers.
• Dehydration reactions can occur only after hydrolysis.