NDT Chapter 5: Lipids
low density lipoprotein
a lipoprotein formed in the blood from VLDLs; transports cholesterol to the cells of the body
very low density lipoprotein
a lipoprotein made in the liver and intestine that functions to transport endogenous lipids, especially triglycerides, to the tissues of the body
high density lipoprotein
a lipoprotein made in the liver and released into the blood; transports cholesterol from the tissues back to the liver
chylomicron
a lipoprotein produced in the interior sites; transports dietary fat out of the intestinal tract
docosahexaenoic acid (DHA)
a metabolic derivative of Alpha-linolenic/omega 3 fatty acids acid semicolon also available from Marine foods
triglyceride
a molecule consisting of Three fatty acids attached to a three-carbon glycerol backbone
lipoprotein
a spherical compound in which fat clusters in the center and phospholipids and proteins form the outside of the sphere
micelle
a spherical compound made up of bile salt and biliary phospholipids that transports lipid digestion products to the intestinal mucosal cell
sterols
a type of lipid found in foods and the body that has a ring structure;
phospholipids
a type of lipid in which a fatty acid is combined with another compound that contains phosphate; unlike other lipids, phospholipids are soluble in water
Linoleic acid and alpha-linolenic acid __________ -are non-essential fatty acids -cannot be synthesized in the body -are found only in meats -should not be consumed in a healthy diet
cannot be synthesized in the body
The hormone _______________________ stimulates the gallbladder to release bile through the common bile duct into the duodenum
cholecystokinin
The enzyme _________________, secreted from the chief cells in the stomach, begins the digestion of some triglycerides
gastric lipase
The structure composed of a glycerol backbone and one fatty acid is called a ____________________
monoacylglyceride
Fatty acids with one double bond between two of their carbon atoms are referred to as -saturated -polyunsaturated -monounsaturated -steroids
monounsaturated
Which of the following foods is the best source of monounsaturated fatty acids? -skim milk -olive oil -sour cream -corn oil
olive oil
A lipid that the body requires to make several critical substances but can't synthesize on its own is _____. -cholesterol -vitamin D -phosphates -omega-3 fatty acids
omega-3 fatty acids
This enzyme, which catalyzes the hydrolysis of the two fatty acids from the glycerol backbone in the intestine, is called ______________
pancreatic lipase
Which enzyme is responsible for the majority of the digestions of lipids? -pancreatic lipase -bile -lingual lipase -gastric lipase
pancreatic lipase
part ii of lipid digestion in the small intestine:
pancreatic lipase can then access the triglycerides and break them apart into free fatty acids and monoacylglycerol
This compound, which is the most common lipid in foods, is made up of three fatty acids attached to a glycerol backbone and is called a ____________
triglyceride
HDL is low in what kind of lipid
triglycerides and cholesterol
T/F Triglycerides are the most common lipid found in foods
true
trans fatty acid
type of fatty acid in which the hydrogen atoms are attached on diagonally opposite sides of the double carbon Bond
The most healthful dietary lipid to consume is __________. -cholesterol -unsaturated fat -trans fat -saturated fat
unsaturated fat
The AMDR for fat is -10% to 25% of total energy. -20% to 35% of total energy. -There is no AMDR for fat. -15% to 30% of total energy.
20% to 35% of total energy.
eicosapentaenoic acid (EPA)
A metabolic derivative of alpha-linolenic acid/omega 3 fatty acids. also available from marine foods
fatty acid
an acid composed of a long chain of carbon atoms bound to each other as well as to hydrogen atoms, with a carboxyl group at the alpha end of the chain
linoleic acid
an essential fatty acid found in vegetable and nut oils; an omega-6 fatty acid
Which of the following foods contains primarily saturated fats? -butter -skim milk -olive oil -peanuts
butter
examples of visible fats
butter, margarine, cream, shortening, salad dressings, chicken skin, and untrimmed fat on meat
LDL is high in what kind of lipid
cholesterol
what is the most common sterol that is occurs in our diets
cholesterol
invisible fats
fats that are headed in foods, such as the fats found in baked goods
short chain fatty acids
fatty acids fewer than six carbon atoms in length
This alcohol, called __________, is made up of three carbons, three hydroxyl groups, and five hydrogen ions
glycerol
The risk for cardiovascular disease is reduced in people who have high blood levels of -very-low-density lipoproteins. -triglycerides -high-density lipoproteins. -low-density lipoproteins
high-density lipoproteins.
Saturated fatty acids are saturated with _____ -glycerol -carbon -fat -hydrogen
hydrogen
Triglycerides within chylomicrons are taken up by body cells with the help of -lipoprotein lipase -bile. -gastric lipase -pancreatic lipase
lipoprotein lipase
what is bad cholesterol
low-density lipoprotein
what is the function of phospholipids?
transport fat in the bloddstream
function of chylomicrons
transports dietary fat into the blood and to the tissues of the body
what is the function of VLDL
transports endogenous lipids, especially triglycerides, to various tissues of the body
VLDL is high in what kind of lipid
triglycerides
chylomicron is high in what kind of lipid
triglycerides
T/F Lecithin is a sterol found in egg yolks
FALSE
T/F Trans fatty acids are byproducts of certain types of food processing; they do not occur in nature.
FALSE
How much of your daily caloric intake should come from all fats? -10% to 20% -5% to 10% -40% to 45% -20% to 35%
20% to 35%
T/F Fat is unhealthful, and we should consume as little as possible.
FALSE
The FDA has banned manufactures from adding trans fatty acids in the form of hydrogenated oils to processed food products. Trans fatty acid intake is highly coorelated with heart disease and thei intake should be limited. Which foods naturally contain trans fatty acids? -Nuts butters and avocados -Canola and safflower oils -Beef, butter, full fat dairy products
Beef, butter, full fat dairy products
Lipoproteins are classified by their density. Low-density lipoproteins are associated with high risk of heart disease because they are most dense in -Cholesterol -Micelles -Protein -Triglycerides
Cholesterol
Which statement below is TRUE about cholesterol -Cholesterol is found in animal products including beef and chicken. -Pecans are a rich source of cholesterol. -Cholesterol is the major fat in the diet of Americans -Cholesterol is an essential nutrient and must be consumed in the diet.
Cholesterol is found in animal products including beef and chicken
what is good cholesterol
High-density lipoprotein (HDL)
____________ always have two or more double bonds between adjacent carbon atoms in the fatty acid chain, making them liquid at room temperature. -Saturated fatty acids -Polyunsaturated fatty acids -Monounsaturated fatty acids -Unsaturated fatty acids
Polyunsaturated fatty acids
Which of the following foods most likely contains invisible fat? -Bacon -orange slices -Green leafy salad (no salad dressing) -Potato chips
Potato chips
All fats are part of a larger group known as lipids. Lipids come in Choose the statement below that correctly describes the types of lipids found in food -Triglycerides contain two fatty acids attached to a glycerol backbone. -All fatty acids in triglycerides have 6 to 12 carbons per chain. -The body does not manufacture phospholipids, so they must be included in the diet. -Sterols like cholesterol have a ring structure.
Sterols like cholesterol have a ring structure.
T/F During a long bike ride, lipids are mobilized from adipose tissue for use as energy.
TRUE
T/F Fried foods are relatively nutritious as long as vegetable shortening is used to fry the foods
TRUE
T/F High-fat diets cause cancer
TRUE
T/F To reduce your risk for cardiovascular disease, avoid eating most of your Calories in the evening before bed
TRUE
__________ have "kinked" fatty acids at the area of their double bonds, preventing them from packing tightly together -Trans fats -Unsaturated fats -Saturated fats -Sterols
Unsaturated fats
Atherosclerosis
a disease in which arterial walls accumulate deposits of lipids and scar tissue, which build up to a point at which they impair blood flow
Fats are ________________ -provide less energy, gram for gram, than carbohydrates, but are metabolized more efficiently. -keep foods from turning rancid. -enable the digestion of fat-soluble vitamins -are a major source of fuel for the body both during physical activity and at rest
are a major source of fuel for the body both during physical activity and at rest
Which of the following foods is the best source of polyunsaturated fatty acid? -olive oil -avocado -steak -corn oil
corn oil
Your cousin has a BMI of 29.5 and has just learned he has atherosclerosis. What would be the best strategies for him to lower his risk of a heart attack? -increase his physical activity, consume plenty of fruits and vegetables, and consume oily fish at least twice weekly -increase his physical activity, consume plenty of fruits and vegetables, and consume at least three alcoholic beverages daily -start smoking to help him lose weight, consume processed foods, and consume oily fish at least twice weekly -lose weight, consume whole foods, and avoid consuming fish
increase his physical activity, consume plenty of fruits and vegetables, and consume oily fish at least twice weekly
To reduce your risk for cancer, the American Cancer Society (ACS) recommends that you __________. -maintain a healthful body weight -select processed meats instead of red meat -drink two glasses of red wine daily -eat at least 5 cups of fruits and vegetables each day
maintain a healthful body weight
Which of the three lipids commonly found in foods are used to manufacture cell membranes -sterols -phospholipids -triglycerides -None of these lipids is used in cell membranes
phospholipids
Three healthful sources of beneficial fats are -skim milk, lamb, and fruits. -oats, broth-based soups, and red wine. -whole milk, egg whites, and stick margarine -plant oils, fish, and seeds
plant oils, fish, and seeds
part iii of lipid digestion in the small intestine:
products from lipase digestion along with cholesterol are trapped in the micelle
Which of the following individuals would likely have the lowest risk for cardiovascular disease? -someone who eats only invisible fats -someone who eats steak, burgers, and ice cream daily -someone who eats processed foods or fast food five to six days a week -someone who eats fish or vegetarian meals five or more days a week
someone who eats fish or vegetarian meals five or more days a week
part vi of lipid digestion in the small intestine:
within enterocytes, components from micelles reform triglycerides and are repackaged as chylomicrons for transport into the lymphatic system
what is the function of lipoproteins?
transport lipids into the bloodstream
what is the function of HDL
transports cholesterol from tissues back to the liver
what is the function of LDL
transports cholesterol to the cells of the body
From the list below, choose all the correct statements about the functions of fat. -Fat is a good source of energy, providing 4 kcal/g. -Fat provides flavor and texture to food (think ice cream) and also leaves you satisfied for longer after a meal. -Lipids are an essential component of cell membranes, provide materials needed to make steroid hormones, act as insulation under the skin, and protect organs from injury. -The body can rely on carbohydrate stores during periods of low energy intake. -Fat in the diet allows for the transport of vitamins A, C, and E because they are fat-soluble.
-Fat provides flavor and texture to food (think ice cream) and also leaves you satisfied for longer after a meal. -Lipids are an essential component of cell membranes, provide materials needed to make steroid hormones, act as insulation under the skin, and protect organs from injury.
what does the gallbladder secrete during lipid digestion
-bile
what does the stomach secrete during lipid digestion
-gastrin -gastric lipase
Which diet or lifestyle changes are recommended to reduce cancer risk? -increase intake of high-fiber plant foods -choose refined grains over whole grains -limit alcohol to three drinks per day for men, two drinks per day for women -choose fish, poultry, and beans instead of red meat
-increase intake of high-fiber plant foods -choose fish, poultry, and beans instead of red meat
what does the mouth secrete during lipid digestion
-lingual lipase
what happens in the mouth during lipid digestion?
-lingual lipase secreted by tongue cells and mixed with saliva digests some triglycerides -little lipid digestion occurs here
what are the two essential fatty acids
-linoleic acid -alpha-linolenic acid
what happens in the stomach during lipid digestion?
-most fat arrives intact at this organ, where it is mixed and broken into droplets -gastric lipase digests some trigylcerides
what does the pancreas secrete during lipid digestion
-phospholipase -pancreatic lipase
what are the health effects of omega-3 fatty acids?
-reduce risk of heart disease -reduce inflammatory responses -reduce blood clotting and plasma triglycerides
what does the small intestine secrete during lipid digestion
-secretin -cholecystokinin
From the list below, choose the types of fat that should be limited in a person's diet, assuming his or her consumption of total fat is within the recommended range of 20% to 35% of daily energy -trans fat -polyunsaturated fat -saturated fat -monounsaturated fat -essential fatty acids
-trans fat -saturated fat
Lard is a solid fat composed mainly of saturated fatty acids (SFAs). What feature of SFAs contributes to the solidity of lard? -Double bonds join carbons in the SFA chain. -All carbons in SFAs are joined with single bonds. -SFAs have several kinks in the chain. Carbon bonds in -SFAs are in the cis formation
All carbons in SFAs are joined with single bonds.
Choose the statement below that correctly describes the relationship between dietary fat and chronic heart disease. -To lower risk of heart disease, trans fats should be kept to 5% to 6% of total energy intake. -A diet high in omega-3 fatty acids may lower the risk of heart disease by raising low-density lipoproteins (LDL). -Diets high in trans fat increase blood levels of high-density lipoproteins (HDL), or the "bad cholesterol," and, therefore, increase risk for heart disease. -Diets high in fat, simple sugars, and excess calories increase blood levels of triglycerides, and, therefore, increase risk of heart disease.
Diets high in fat, simple sugars, and excess calories increase blood levels of triglycerides, and, therefore, increase risk of heart disease.
T/F A serving of food labeled reduced fat has at least 25% fewer Calories than a full-fat version of the same food
FALSE
T/F Certain fats protect against heart disease
FALSE
T/F Dietary cholesterol is not required because our body makes all the cholesterol it needs
FALSE
Which of the following statements is NOT a function of fat in the body -Fats provide structure to cell membranes. -Fats are a major energy source during rest. -Fats transport fat-soluble vitamins. -Fats function to repair damaged muscle
Fats function to repair damaged muscle
Which of the following statements regarding the structure of triglycerides is TRUE -Fatty acid chains in a triglyceride molecule, which contain a single double bond, are referred to as monounsaturated fatty acids. -A triglyceride consists of a fatty acid with three glycerol molecules attached. -Unsaturated fatty acids have only one shape, referred to as a cis configuration, which bends at the double bond. -Fatty acid chains in a triglyceride molecule with more than one double bond are referred to as saturated fatty acids
Fatty acid chains in a triglyceride molecule, which contain a single double bond, are referred to as monounsaturated fatty acids.
Choose the correct statement about enzymes that assist with fat digestion. -Lipoprotein lipase is found on the inside of body cells. -Lingual lipase is secreted by the stomach to digest some triglycerides. -Triglyceride digestion requires pancreatic lipase. -Gastric lipase is released by the tongue during chewing
Triglyceride digestion requires pancreatic lipase.
glycerol
an alcohol composed of three carbon atoms; it is the backbone of a triglyceride molecule
lipoprotein lipase
an enzyme that sits on the outside of cells and breaks apart triglycerides, so that their fatty acids can be removed and taken up by the cell
alpha linoleic acid
an essential fatty acid found in leafy green vegetables, flaxseed oil, soy oil, fish oil, and fish products; and omega-3 fatty acid
Fat digestion begins when fats are emulsified by __________ -lipoproteins -chylomicrons -the stomach -bile
bile
When fat enters the duodenum, an emulsifier called ________ is released into the small intestine to break up the large fat globules into smaller fat droplets
bile
What are micelles? -emulsifiers used to break fat globules into small droplets during digestion -lipid-digesting enzymes located in the small intestine -a type of lipoprotein needed to absorb lipids -clusters of fatty acids, monoglycerides, and other lipids surrounded by bile salts that transport lipids across the cell membrane of the villi
clusters of fatty acids, monoglycerides, and other lipids surrounded by bile salts that transport lipids across the cell membrane of the villi
Sophie would like to increase her intake of omega-3 fatty acids. Which of the following would NOT be an effective strategy? -eat hamburgers made with ground beef that is 80% lean -replace her weekly grilled steak with grilled salmon -make a salad dressing with canola oil and balsamic vinegar -add walnuts to yogurt and salads
eat hamburgers made with ground beef that is 80% lean
All of the following are ways to lower your saturated fat intake EXCEPT ___________ -choosing yellow cake instead of angel food cake -eating baked tortilla chips in place of regular chips -using wine, lemon juice, or broth instead of butter -baking or broiling in place of frying
eating baked tortilla chips in place of regular chips
T/F Foods contain only one type of fatty acid, either saturated or unsaturated, but never both
false
T/F Lipids enter the bloodstream directly after digestion.
false
long chain fatty acids
fatty acids that are 14 or more carbon atoms and length
medium chain fatty acids
fatty acids that are 6 to 12 carbon atoms in length
polyunsaturated fatty acids
fatty acids that have more than one double bond in the chain semicolon these types of fatty acids are generally liquid at room temperature
saturated fatty acid
fatty acids that have no carbons joined together with a double bond; these types of fatty acids are generally solid at room temperature
monounsaturated fatty acids
fatty acids that have two carbons in the chain bound to each other with one double bond; these types of fatty acids are generally liquid at room temperature
essential fatty acids
fatty acids that must be consumed in the diet because they cannot be made by the body
A good source of EPA and DHA in the diet is _____. -fried foods -lettuce -fatty fish -oats
fatty fish
Alpha-linolenic acid (ALA) is -found in leafy green vegetables, flaxseed oil, and fatty fish -a precursor to linoleic acid -also known as arachidonic acid. -a metabolic derivative of EPA and DHA
found in leafy green vegetables, flaxseed oil, and fatty fish
The lipid profile associated with the lowest risk of cardiovascular disease is __________ -high HDL, low LDL, low triglycerides -high HDL, low LDL, high triglycerides -high HDL, high LDL, low triglycerides -low HDL, low LDL, low triglycerides
high HDL, low LDL, low triglycerides
visible fats
if that's we can see in our food or see added to foods
Trans fatty acids -increase the blood's level of the lipids associated with cardiovascular disease. -are synthesized in the liver and intestine, and therefore do not need to be consumed in the diet -have double carbon bonds in which both hydrogen atoms are located on the same side of the double bond. -have no double carbon bonds
increase the blood's level of the lipids associated with cardiovascular disease
part i of lipid digestion in the small intestine:
large fat droplets filled with triglycerides are emulsified (broken down) by bile into smaller droplets
To lower risk of cardiovascular disease, the Dietary Guidelines for Americans recommends __________ of daily kcal come from saturated fat -less than 10% -10% to 11% -less than 20% -20% to 35%
less than 10%
a diverse group of organic substances that are insoluble in water
lipids
Long-chain fatty acids are transported via chylomicrons from inside the enterocyte into the _________________ to be delivered to the rest of the body
lymphatic system
The products of lipid hydrolysis are transported to the enterocytes in ________________
micelles
part v of lipid digestion in the small intestine:
micelles transport lipid digestion products to the enterocytes
examples of invisible fats
regular-fat dairy products, marbling in meat, and fried foods
Choose the meal below that contains primarily healthful fats -roasted salmon, spinach sautéed in olive oil, brown rice, and toasted walnuts -roasted turkey breast (no gravy), broccoli topped with 2 tablespoons of shredded cheddar cheese, and mashed potatoes made with cream and butter -fried chicken breasts from a fast-food restaurant, a green salad with no dressing, mac and cheese, and green beans with butter -grilled hamburger patty (85% lean) on a whole-wheat bun, raw carrots and celery with 1/4 cup of blue cheese dressing, and buttered corn on the cob
roasted salmon, spinach sautéed in olive oil, brown rice, and toasted walnuts
The fish that contain greater quantities of EPA and DHA, omega-3 fatty acids known to benefit health, are __________. -fish sticks and fried white fish -cod and haddock -salmon and tuna -tilapia and mahi mahi
salmon and tuna
Which type of fatty acid is most common in animal-based foods, such as steak, butter, and milk? -polyunsaturated fat -monounsaturated fat -saturated fat
saturated fat
part vii of lipid digestion in the small intestine:
shorter fatty acids can be absorbed directly into the bloodstream
part iv of lipid digestion in the small intestine:
the micelle transports these digestion products to the intestinal enterocyte to be absorbed
hydrogenation
the process of adding hydrogen to unsaturated fatty acids, making them more saturated in thereby more solid at room temperature
what is the function of plant sterols?
they appear to block the absorption of dietary cholesterol
How many different forms of lipids are commonly found in food -four -two -three -six
three