Deck 5: The Lipids: Triglycerides, Phospholipids, and Sterols

Question 1

How many double bonds are present in stearic acid?

A) 0
B) 1
C) 2
D) 3

Answer 1

A

Question 2

What are lipids that are solid at room temperature known as?

A) oils
B) fats
C) omegas
D) glycerols

Answer 2

B

Question 3

Which of the following describes a fatty acid that has 1 double bond?

A) saturated
B) hydrogenated
C) monounsaturated
D) polyunsaturated

Answer 3

C

Question 4

Which of the following is a common source of medium-chain fatty acids?

A) fish oils
B) beef products
C) vegetable oils
D) dairy products

Question 5

Lipids differ in their degree of saturation or unsaturation due to their number of which of the following factors?

A) the number of amino acids
B) the number of double bonds
C) the number of saccharide units
D) the number of peptide linkages

Question 6

Which of the following is a common dietary saturated fatty acid?

A) oleic acid
B) stearic acid
C) linolenic acid
D) arachidonic acid

Question 7

What compound is composed of 3 fatty acids and glycerol?

A) steroid
B) lecithin
C) triglyceride
D) monoglyceride

Question 8

In which one of the following forms are most dietary lipids found?

A) sterols
B) glycerols
C) triglycerides
D) monoglycerides

Question 9

What is the simplest fatty acid found in the diet?

A) oleic acid
B) acetic acid
C) linoleic acid
D) palmitic acid

Question 10

How many hydrogen atoms are attached to each carbon adjacent to a double bond?

A) 1
B) 2
C) 4
D) 6

Question 11

Which of the following is a property of dietary lipids?

A) Omega-3 fatty acids are always unsaturated.
B) Lipids that are solid at room temperature are classified as oils.
C) The fatty acids in triglycerides may be of chain length 2 to 25 carbons.
D) The most common fatty acid chain length in triglycerides is 10 carbons.

Question 12

What is the chemical composition of fats?

A) hexose polymers
B) glycogen granules
C) fatty acids and glycerol
D) combinations of long-chain fatty acids

Question 13

What are lipids that are liquid at room temperature known as?

A) oils
B) fats
C) omegas
D) glycerols

Question 14

Approximately what percentage of the lipids in foods are triglycerides?

A) 5 percent
B) 30 percent
C) 95 percent
D) 100 percent

Question 15

Approximately how many carbons are contained in a medium-chain fatty acid?

A) 2-4
B) 6-10
C) 12-22
D) 24-26

Question 16

Which of the following is a polyunsaturated fatty acid in foods?

A) oleic acid
B) acetic acid
C) stearic acid
D) linoleic acid

Question 17

Which of the following represents a chief source of short-chain and medium-chain fatty acids?

A) fish
B) eggs
C) dairy
D) soybeans

Question 18

A compound composed of carbon, hydrogen, and oxygen with 3 fatty acids attached to a molecule of glycerol would be known as which of the following?

A) a diglyceride
B) a triglyceride
C) a phospholipid
D) a monoglyceride

Question 19

What is the simplest 18-carbon fatty acid?

A) stearic acid
B) linoleic acid
C) palmitic acid
D) linolenic acid

Question 20

What percentage of stored body fat is in the form of triglycerides?

A) 2 percent
B) 50 percent
C) 78 percent
D) 99 percent

Question 21

When stored at room temperature in loosely capped containers, which of the following dietary lipids would turn rancid in the shortest time?

A) lard
B) peanut oil
C) soybean oil
D) coconut oil

Question 22

Which of the following foods should a person wishing to increase consumption of polyunsaturated fats choose?

A) coconut oil
B) beef products
C) vegetable oils
D) dairy products

Question 23

Which of the following fats would be most solid at room temperature and most resistant to oxidation?

A) tropical oils
B) omega-3 enriched, trans-fat-free margarine
C) flaxseed oil
D) corn oil subjected to full hydrogenation

Question 24

Which of the following characteristics is shared by olive oil and canola oil?

A) Neither is liquid at room temperature.
B) Neither contains saturated fatty acids.
C) Both contain high levels of polyunsaturated fatty acids.
D) Both contain high levels of monounsaturated fatty acids.

Question 25

Which of the following is a factor that determines the hardness of a fat at a given temperature?

A) origin of the fat
B) degree of saturation
C) number of acid groups
D) number of oxygen atoms

Question 26

Which of the following would be least effective at preventing oxidation of the polyunsaturated fatty acids in processed foods?

A) refrigeration
B) addition of BHT
C) partial hydrogenation
D) addition of phosphorus

Question 27

Which of the following has the highest percentage of its fat in saturated form?

A) butter
B) walnut oil
C) beef tallow
D) coconut oil

Question 28

Which of the following structural features of fatty acids determines their susceptibility to spoilage by oxygen?

A) chain length
B) number of double bonds
C) position of first saturated bond
D) size of adjacent fatty acids on the triglyceride molecule

Question 29

What is a triacylglyceride?

A) a triglyceride
B) a phospholipid
C) a partially hydrolyzed lipid
D) a lipid found only in cold-water fish

Question 30

Which of the following sources would yield the softest lipids at room temperature?

A) lard
B) beef
C) pork
D) safflower

Question 31

Which of the following is known as tropical oil?

A) flaxseed oil
B) safflower oil
C) cocoa butter
D) conjugated linoleic acid

Question 32

Which of the following has the highest percentage of its fat in polyunsaturated form?

A) butter
B) corn oil
C) beef tallow
D) coconut oil

Question 33

The easiest way to increase intake of oleic acid is to consume more of which of the following oils?

A) lard oil
B) corn oil
C) olive oil
D) safflower oil

Question 34

Which of the following are all methods used by food processors to stabilize the lipids in food products?

A) refrigeration, hydrogenation, oxidization
B) refrigeration, hydrogenation, tightly sealed packaging
C) refrigeration, metallic packaging, BHT
D) refrigeration, oxidization, BHT

Question 35

Which of the following provides abundant amounts of omega-3 fatty acids?

A) palm oil
B) walnut oil
C) soybean oil
D) flaxseed oil

Question 36

A major cause of rancidity of lipids in foods is exposure to which of the following external factors?

A) exposure to heat and oxygen
B) exposure to fluorescent lighting
C) exposure to freezer temperatures
D) exposure to enrichment additives

Question 37

Which of the following does a triglyceride always contain?

A) 3 water molecules
B) 3 glycerols
C) 3 fatty acids
D) 3 acid groups

Question 38

Which of the following is a feature of polyunsaturated fats?

A) low melting point
B) high melting point
C) solid at room temperature
D) solid at refrigerator temperature

Question 39

Which one of the following compounds is missing 4 or more hydrogen atoms?

A) monounsaturated fatty acid
B) polyunsaturated fatty acid
C) long-chain saturated fatty acid
D) short-chain saturated fatty acid

Question 40

What type of fatty acid is found in high amounts in olive oil?

A) saturated
B) monounsaturated
C) polyunsaturated
D) partially hydrogenated

Question 41

To which part of the molecule are hydrogen atoms added during the process of fat hydrogenation?

A) oxygen
B) carbon
C) glycerol
D) other hydrogens

Question 42

On which of the following lipids does the food industry often carries out the process of hydrogenation?

A) corn oil
B) olive oil
C) beef tallow
D) coconut oil

Question 43

Which advice regarding lecithin supplementation would be most consistent with current evidence?

A) Supplements are recommended for those who bruise easily and they support the integrity of cell membranes.
B) Supplements are recommended after gallbladder removal to assist in the emulsification of fats in the digestive tract.
C) Supplements are not recommended since adequate lecithin is manufactured by the body
D) Supplements are not recommended since lecithin inhibits fat absorption

Question 44

Oil that is partially hydrogenated sometimes changes one or more of its double-bond configurations. Which of the following is the correct change?

A) from cis to trans
B) from solid to liquid
C) from covalent to ionic
D) from saturated to unsaturated

Question 45

Which of the following is a feature of choline?

A) It is a part of lecithin.
B) It is a type of cis-fatty acid.
C) It is a type of trans-fatty acid.
D) It is attached to omega-3 fatty acids.

Question 46

Which of the following lipids contain(s) saturated fat?

A) butter only
B) soybean oil only
C) cottonseed oil only
D) butter, cottonseed oil, and soybean oil

Question 47

Which of the following is considered a major source of polyunsaturated fat?

A) corn oil
B) palm oil
C) peanut oil
D) chicken fat

Question 48

Which of the following characteristics differentiates fully hydrogenated fats from saturated fats?

A) They retain some double bonds.
B) They are more susceptible to oxidation.
C) They contain trans fatty acids.
D) They have a shorter shelf life.

Question 49

Which carbon(s) of an omega-3 fatty acid has/have the first double bond?

A) third carbon from the acid end
B) first 3 carbons from the acid end
C) third carbon from the methyl end
D) first 3 carbons from the methyl end

Question 50

Which of the following is descriptive of trans fatty acids?

A) They result from hydrogenation of saturated fatty acids.
B) They have a folded, U-shape formation.
C) They are made only from polyunsaturated fats.
D) They occur naturally in dairy products.

Question 51

What type of compound is lecithin?

A) bile salt
B) glycolipid
C) lipoprotein
D) phospholipid

Question 52

Which of the following is a feature of phospholipids?

A) resistant to digestion
B) soluble in both water and fat
C) highly susceptible to oxidation
D) found naturally only in animal foods

Question 53

What is a conjugated linoleic acid?

A) a type of cis-fatty acid
B) a partially hydrogenated omega-6 lipid
C) a fatty acid with the chemical make-up of linoleic acid but with a different configuration
D) a fatty acid resulting from the partial hydrolysis of dietary phospholipids in the intestinal tract

Question 54

Which of the following is a characteristic of lecithin supplements?

A) mostly hydrolyzed in the intestine
B) contribute small amounts of magnesium
C) have an energy content of 4 kcalories per gram
D) contribute large amounts of omega-3 fatty acids

Question 55

What of the following is the usual fate of dietary lecithin?

A) unabsorbed and passes out in the feces
B) absorbed intact and incorporated into tissues
C) absorbed intact and broken down by the liver
D) hydrolyzed by the intestinal enzyme lecithinase

Question 56

Which of the following describes a feature of cis-fatty acids and trans-fatty acids?

A) In nature, most double bonds are trans.
B) Hydrogenation converts trans-fatty acids to cis-fatty acids.
C) The conversion of cis-fatty acids to trans-fatty acids is inhibited by the presence of antioxidants.
D) In the body, trans-fatty acids are metabolized more like saturated fats than like unsaturated fats.

Question 57

What is the approximate energy value of 1 teaspoon of liquid lecithin supplement?

A) 0 kcal
B) 2 kcal
C) 45 kcal
D) 200 kcal

Question 58

How much energy is contributed by 1 gram of lecithin in a dietary supplement?

A) 0 kcal
B) 4 kcal
C) 7 kcal
D) 9 kcal

Question 59

The composition of lecithin is differentiated from a triglyceride due to which of the following components?

A) choline and glycerol
B) phosphate and cholesterol
C) fatty acids and nitrogen
D) choline and phosphate

Question 60

Which of the following has the highest concentration of polyunsaturated fatty acids in relation to total fatty acids?

A) palm oil
B) olive oil
C) soybean oil
D) safflower oil

Question 61

Which of the following organs is the storage site of bile?

A) liver
B) pancreas
C) gallbladder
D) common bile duct

Question 62

Which of the following structures is common to both cholesterol and lecithin molecules?

A) sterol ring
B) phosphate group
C) glycerol
D) methyl groups

Question 63

In the digestion of fats, emulsifiers function as which of the following compounds?

A) enzymes
B) hormones
C) detergents
D) chylomicrons

Question 64

About how much cholesterol is synthesized by the liver every day?

A) 0 mg
B) 150 mg
C) 300 mg
D) at least 800 mg

Question 65

Which of the following is a common feature of the plant sterols?

A) They raise LDL and lower HDL.
B) They inhibit absorption of dietary cholesterol.
C) They inhibit absorption of "bad" cholesterol.
D) They enhance absorption of omega-3 fatty acids.

Question 66

What is the major sterol in the diet?

A) testosterone
B) bile acids
C) cholesterol
D) Vitamin D

Question 67

Which of the following may act as emulsifiers in the intestinal lumen?

A) lecithin and pancreatic lipase
B) bile acids and lipoproteins
C) pancreatic lipase and lipoproteins
D) bile acids and lecithin

Question 68

Which of the following dietary fats is found in animal sources only?

A) cholesterol
B) triglycerides
C) essential fatty acids
D) nonessential fatty acids

Question 69

Which of the following reflects current dietary advice about cholesterol?

A) An individual consuming a 2000 kcal diet should eat no more than 300 mg cholesterol per day.
B) Intake of "good cholesterol" is encouraged, but intake of "bad" cholesterol should be as low as possible.
C) Cholesterol from plant sources should be consumed daily to reduce the absorption of cholesterol from animal sources.
D) There are no formal recommendations regarding dietary cholesterol since intake is much lower than endogenous synthesis.

Question 70

Which of the following is the best reason to limit dietary cholesterol?

A) Dietary cholesterol is a precursor of Vitamin D which can be toxic in high doses.
B) Foods high in dietary cholesterol are often high in saturated fat and energy.
C) Dietary cholesterol is a precursor of steroid hormones and can produce weight gain.
D) Dietary cholesterol is the main source of total body cholesterol deposits.

Question 71

What term may be used to describe a substance that is hydrophobic?

A) lipophilic
B) lipophobic
C) glycerophilic
D) glycerophobic

Question 72

Which of the following is the major source of "good" cholesterol?

A) tissue breakdown
B) exogenous synthesis
C) endogenous synthesis
D) resorption from the GI tract

Question 73

Which of the following is a destination for cholesterol in the body?

A) synthesis into bile in the liver
B) excretion in the urine
C) accumulation on walls of veins
D) storage within triglycerides in adipose tissue

Question 74

Which of the following lipase enzymes is responsible for most fat digestion in adults?

A) gastric lipase.
B) intestinal mucosal lipase
C) salivary gland lipase (lingual lipase)
D) pancreatic lipase

Question 75

Which of the following is a characteristic of cholesterol?

A) It is absorbed directly into the blood.
B) It is a precursor for bile and vitamin D synthesis.
C) It is not formed in the body when provided by the diet.
D) It is found in abundance in tropical fats such as palm oil.

Question 76

Which of the following describes the main path of bile in the body?

A) synthesized in the liver, stored in the gallbladder, reabsorbed from the small intestine
B) synthesized from cholesterol in the small intestine, reabsorbed in the large intestine, stored in the gallbladder
C) synthesized in the gallbladder, emulsifies fat in the small intestine, reabsorbed in the large intestine
D) synthesized in the gallbladder, emulsifies fat in the small intestine, excreted in feces via the colon.

Question 77

Which of the following foods contains cholesterol?

A) corn
B) olives
C) roasted turkey
D) roasted peanuts

Question 78

Which of the following compounds may be synthesized from cholesterol?

A) cholecystokinin (CCK)
B) glucose
C) vitamin C
D) sex hormones

Question 79

Bile is known to assist in the absorption of which of the following nutrients?

A) fat only
B) protein only
C) carbohydrate only
D) fat and protein only

Question 80

Which of the following is a property of cholesterol?

A) Only about 10 percent of the body's total cholesterol is extracellular.
B) "Bad" cholesterol is a form of cholesterol found in plant foods.
C) "Good" cholesterol is a form of cholesterol found in plant foods.
D) Exogenous cholesterol absorption is reduced by lecithin supplements.