Quiz 3 Review

*Which process requires ATP?* A.Diffusion B.Passive transport C.Osmosis D.Active transport

Active transport

*Detergents are efficient emulsifiers particularly because of their* A.amphoteric properties B.amphipathic properties C.aliphatic properties D.aromatic properties

amphipathic properties

*Phospholipids and fatty acids, and their degree of saturation, have far-reaching implications for membrane transport and fluidity. Which of the following is a correct statement?* A.A saturated fatty acid has more double bonds than an unsaturated fatty acid B.A species in a cold environment will tend to have more double bonds in the fatty acids of their phospholipids compared to a species in a warm environment C.A species in a cold environment will tend to have less double bonds in the fatty acids of their phospholipids compared to a species in a warm environment D.If the proportion of double bonds in a phospholipid increases, the fluidity of the membrane will decrease

A species in a cold environment will tend to have more double bonds in the fatty acids of their phospholipids compared to a species in a warm environment

*Which of the following is the best explanation for why animal fats (but not vegetable oils) are solid at room temperature?* A.Animal fats have more double bonds than vegetable oils do B.Animal fats have fewer double bonds than vegetable oils do C.Animal fats have shorter fatty-acid tails than vegetable oils have D.Animal fats have a lower concentration of sterols

Animal fats have a lower concentration of sterols

*Which of the following is true of carrier proteins that are used in facilitated diffusion?* A.Carrier proteins used in facilitated diffusion are usually coupled to ATP hydrolysis B.Carrier proteins used in facilitated diffusion are specific for a specific type of molecule C.Carrier proteins used in facilitated diffusion are located in the nuclear membrane D.Carrier proteins used in facilitated diffusion work against concentration gradients

Carrier proteins used in facilitated diffusion are specific for a specific type of molecule

*Which of the following is not a lipid?* A.Prostaglandin B.Linolenic acid C.Galactocerebroside D.Glycine

Glycine

*Which of the following is correct about fat-soluble vitamins?* I. Vitamin E is important for calcium regulation. II. Vitamin D protects against cancer because it is a biological antioxidant. III. Vitamin K is necessary for the posttranslational introduction of calcium-binding sites. IV. Vitamin A is metabolized to retinal, which is important for sight. A.III only B.I and II only C.III and IV only D.II, III, and IV only

III and IV only

*Which of the following properties can be expected in an transmembrane protein?* A.Large amount of hydrophilic residues B.Mostly beta-sheet structures C.Large amount of hydrophobic residues D.A disproportionate amount of histidine

Large amount of hydrophobic residues

*Which of the following statements regarding prostaglandins is FALSE?* A.Prostaglandins regulate the synthesis of cAMP. B.Prostaglandin synthesis is inhibited by NSAIDs. C.Prostaglandins affect pain, inflammation, and smooth muscle function. D.Prostaglandins are endocrine hormones, like steroid hormones.

Prostaglandins are endocrine hormones, like steroid hormones.

*Given the same weight of each, from which macromolecule can the most heat be generated in a combustion reaction?* A.Polyunsaturated fat B.Saturated fat C.Carbohydrate D.Nucleic acid E.Protein

Saturated fat

*Biologists often view the membrane of a neuron as a capacitor, because it separates charged ions inside and outside the membrane. Which of the following changes to the membrane would allow for increased ability of the membrane to separate charge?* A.Longer fatty acid chains in the phospholipid membrane. B.Shortening the fatty acid chains in the phospholipid membrane. C.Inserting magnesium ion symporters in the membrane. D.None of the above

Shortening the fatty acid chains in the phospholipid membrane.

*The melting points (in degrees Celsius) of four different unsaturated 18-carbon fatty acids are as such: 70, 20, -5, and -15. Which of the following best describes this trend?* A.The melting point increases as the number of cis double bonds in the fatty acid increases B.The melting point decreases as the number of cis double bonds in the fatty acid increases C.The melting point increases as the number of trans double bonds in the fatty acid increases D.The melting point is unaffected by the number and types of double bonds present within the fatty acids

The melting point decreases as the number of cis double bonds in the fatty acid increases

*The hydropathy plot shown provides which of the following information?* A.The protein being analyzed is a globular, peripheral membrane protein B.The membrane being analyzed has a high proportion of long chain ( as opposed to short chain) fatty acids. C.The protein being analyzed has extensive Beta-Barrel domains D.The protein being analyzed may be an integral membrane protein with one membrane spanning domains. E.The protein being analyzed may be an integral membrane protein with three membrane spanning domains.

The protein being analyzed may be an integral membrane protein with one membrane spanning domains.

*In studying how a novel compound enters cells, researchers notice the compound moves against its concentration gradient across the cell membrane. Which of the following can be concluded about the mechanism of transport?* A.The transport is active unless the compound is small and nonpolar in which case it is moving via simple diffusion. B.The transport is passive unless it is large and polar in which case it is moving via active transport. C.The transport is passive regardless of the size and charge of the compound. D.The transport is active regardless of the size and charge of the compound.

The transport is active regardless of the size and charge of the compound.

*Which of the following describes the primary structural difference between phospholipids and triglycerides?* A.Phospholipids are triglycerides with a phosphate attached at the end of the fatty acid tails. B.Triglycerides contain three fatty acid chains while phospholipids contain only two, with the third position being a phosphate group. C.Phospholipids are steroid compounds while triglycerides are fat compounds. D.Phospholipids use a 2-carbon compound to bind their fatty acids while triglycerides use a 3-carbon compound to bind their fatty acids.

Triglycerides contain three fatty acid chains while phospholipids contain only two, with the third position being a phosphate group.

*A micelle of a phospholipid forming in a solution of BF3 would be expected to have* A.its polar heads on the inside of the complex B.its polar heads on the outside of the complex C.a mixed arrangement of heads and tails D.a complete dissociation of the micelle phospholipids

its polar heads on the inside of the complex