Unit 6 NSC 101
Rank the statements in order
Bile salts surround fatty acids and monoglycerides to form micelles Micelles transport lipids to the edge of the absorptive cell Absorptive cells remove monoglycerides and fatty acids from micelles
Where else can plaque form?
Common carotid arteries in the neck
Which of the following could be affected by peripheral vascular disease?
Correct: Arteries
Health contribution of essential fatty acids
EPA, DHA, AA make several hormone-like substances. These compounds have a variety of important effects, such as regulating bp and immune system's inflammatory response.
Alpha-linolenic acid
an omega-3 fatty acid The number 3 indicates that first double bond appears in the fatty acids' carbon chains after 3 carbons
Dietary sources of cholesterol are only in what kind of foods?
animal foods: egg yolk, liver, meat, poultry, whole milk, cheese and rice cream are rich sources of cholesterol
Cells can convert linoleic acid to another omega-6 fatty acid:
arachidonic acid (AA)
Statins
are a type of prescription drug that reduces a person's elevated blood lipid levels
Which cuts of meat are the leanest?
arm roast, top round, loin
Peripheral Vascular Disease (PVD)
atherosclerosis affecting a blood vessel that doesn't carry blood to the heart or brain
A diet high in fiber may reduce cholesterol by:
binding the bile salts that contain cholesterol and excreting them in feces
A heart attack is defined as:
blockage in the arteries surrounding the heart causing the tissue to die
Which of the following foods naturally contain small amounts of trans fatty acids?
butter meat whole milk
Most cases of ______ __________ result from atherosclerosis.
cardiovascular disease
angina
chest pain that results from lack of oxygen to heart muscle tissue
LDL is responsible for delivering _____ to the tissues.
cholesterol
______ only comes from animal products.
cholesterol
What does lecithin contain? What does that do?
choline; nerves use it to produce acetylcholine, a chemical that transmits messages between nerve cells
What are some things you can do to reduce fat intake?
choose lean meats bake meats trim fat from meat
lipids
class of organic nutrients that generally don't dissolve in water Functions: maintain cell membranes provide and store energy insulating against cold temps producing certain hormones regulating bp and inflammation cushioning against bumps, blows and falls
Without the presence of bile salt, lipid digestion would result in:
clumped lipids in fatty globules
What do absorptive cells do since lipids are not soluble in watery fluids like lymph and blood?
coat the lipids with a thin layer of protein, phospholipids, and cholesterol to form chylomicrons
bile salts
component of bile
Triglycerides
comprise about 95% of lipids in the body and in food; are often referred to as fats and oils
Cell membranes:
comprised of a double layer that is mostly phospholipids, the phosphate "head" of a phospholipid is water soluble and the fatty acid "tail" of a phospholipid is not water soluble; thus phospholipids are soluble in both water and fat
Food manufactures use the process of hydrogenation to
convert liquid oils into more solid fats
pancreatic lipase
digestive enzyme that removes two fatty acids from each triglyceride molecule
What are some examples of food sources that contain cholesterol?
eggs chicken ice cream NOT peanuts
Cells use alpha-linolenic acid to produce two other omega-3 fatty acids:
eicosaentaenoic acid (EPA) and docosahexaenoic acid (DHA).
lipases
enzymes that break down lipids
Trans fats
fats produced during the hydrogenation process closely resemble the structure of saturated fats, however, due to the altered chemical structure that results during this process they are harmful to health
monounsaturated fatty acid (monounsaturated FA)
fatty acid that has one double bond within the carbon chain
polyunsaturated fatty acid
fatty acid that has two or more double bonds within the carbon chain
saturated fatty acid (saturated FA)
fatty acid that only has single bonds holding each carbon in the carbon chain together
adipose cells are comprised of
fatty acids and glycerol
Foods with lots of saturated fat:
fatty meats, luncheon meats, sausage, hot dogs, and "full-fat" dairy products such as hard cheeses and whole milk
What can lead to the removal of bile salts in the small intestine?
fiber
partial hydrogenation
food manufacturing process that adds hydrogen atoms to liquid vegetable oil, forming trans fats and saturated fats
What are the major products of lipid digestion?
glycerol, fatty acids, and monoglycerides
Which of the following foods tend to contribute a high amount of saturated fat to the diet of Americans?
hard cheese, hot dogs, and sausage
The most common forms of cardiovascular disease in the US include:
stroke, coronary artery disease NOT: cardiomyopathy, endocarditis
Very-low density lipoproteins are formed from:
the remnants of chylomicrons
Which types of fatty acids are associated with increased risk for cardiovascular disease?
trans fatty acids saturated fatty acids
_______ comprise about 95% of lipids in the body and in food. They are often referred to as fats and oils.
triglycerides
phospholipid
type of lipid needed to make cell membranes and for proper functioning of nerve cells
chylomicrons
type of lipoprotein that's formed in the absorptive cells
Trans fatty acids
unsaturated fatty acids that have an unusual type of chemical structure which enables the carbon chain to be relatively straight, compared to other types of unsaturated fatty acids
arteriosclerosis
"hardening of the arteries" condition that results from atherosclerosis
List the steps of dietary fat absorption:
Absorption of glycerol, monoglycerides, and fatty acids into small intestinal cells. Triglycerides are reassembled Lipids are assembled into chylomicrons Chylomicrons enter the lymphatic system
Where and how are lipids digested?
In the small intestine; pancreas releases enzymes (lipases) into the small intestine that digest fats and phospholipids
What happens when pancreatic lipase digests fat by removing two fatty acids from each triglyceride molecule?
It converts most fat into monoglycerides and "free" fatty acids
A lipoprotein that has a high cholesterol content is:
LDL (low-density lipoproteins)
Do fatty acids and triglycerides have carbon rings?
NO
Chemically unstable substances ("free radicals") can damage LDL, especially small dense LDLs. What can the damage result in?
Oxidized LDL cholesterol, which is taken up by the plaque-forming arterial cells
Triglycerides are often referred to as
fats and oils
Adipose cells are designed to store large amounts of:
fats as triglycerides
Which of the following parts make up a monoglyceride?
fatty acid and glycerol backbone
Adipose tissue is comprised of:
glycerol and fatty acids
Fats, oils and cholesterol are:
lipids
atherosclerosis
long-term disease process in which plaque builds up inside arterial walls, causing hardening of the arteries
lecithin
major phospholipid in food: egg yolks, liver, wheat germ, peanut butter, and soy beans are rich sources of it
The structure of phospholipids, having water soluble and water insoluble components, allow phospholipids to form the ____ of the cell.
membrane
Which drug is commonly prescribed to help people reduce elevated blood lipid levels?
statins
lipoprotein
structure that transports lipids through the bloodstream and lymph
Protein
the body can convert certain amino acids into fatty acids
Carbs
the body can convert excess glucose into fatty acids
Rank the following to describe the transformation of triglycerides when energy is needed:
1. Adipose cells break down triglycerides into fatty acids and glycerol molecules 2. Fatty acids and glycerol are released into the bloodstream 3. Cells remove fatty acids from the blood and the liver removes glycerol from the blood 4. Cells metabolize fatty acids for energy and the liver converts glycerol into glucose for energy
List the steps of the development of atherosclerosis in the arteries starting with arterial damage and ending with a heart attack.
1. Damage occurs in blood vessel lining 2. Plaque is deposited at the site of initial damage 3. As plaque accumulated, arteries harden, narrow, and lose elasticity 4. Pressure in artery is increased 5. Clot or spasm in a plaque-clogged artery leads to a heart attack
Order the steps according to how alcohol can lead to CVD disease:
1. Excessive alcohol intake 2. Increased VLDL production in the liver 3. Increased blood triglycerides 4. Cholesterol in HDL decreases
What are the recommendations for intake of saturated and trans fats according to the American Heart Association?
<10% of total calories and as low as possible, respectively
The body cannot make two polyunsaturated FAs, which areL
Alpha-linolenic acid and linoleic acid
Eating foods with fewer trans fats can?
Also lower risk of CVD
What are the primary ways that lipids are transported through the bloodstream?
As part of chylomicrons or lipoproteins
What happens when in the presence of fatty chyme in the duodenum?
The gallbladder releases bile into the chyme and bile salts in bile emulsify the lipids (keep lipids suspended as small particles in chyme. This all helps pancreatic lipase to digest fats molecules.
Which form of unsaturated fatty acid contains a chemical structure similar to that of saturated fatty acids?
Trans fat
Risk Factors of Atherosclerosis:
Unhealthy blood cholesterol levels (high LDL and low HDL) Hypertension Smoking - exposure to tobacco smoke damages and hardens blood vessels, contributing to hypertension, and raises oxidized LDL cholesterol levels Insulin resistance Diabetes Excess body fat Lack of physical activity Poor diet Increasing age Family history of CVD - risk increases if father or brother developed CVD by 55, or if mother or sister developed it by 65
Oxidized LDL is
a bad form because it's formed into plaque
Cardiovascular disease (CVD)
a group of diseases that affect the heart and blood vessels. Cardiovascular disease can result in heart attacks, stores, coronary artery disease and kidney failure.
monoglyceride
a lipid that has a single fatty acid attached to the glycerol backbone of the molecule
What makes up a monoglyceride?
a single fatty acid and a glycerol backbone
Cholesterol
a sterol (carbons arranged in rings) that are a key nutrient and component of cells' membranes, especially in the brain Also used to produce vitamin D, steroid hormones such as estrogen and testosterone Liver uses it to make bile salts, which help small intestine digest lipids
emulsifier
a substance that keeps fat-soluble and water-soluble compounds together
Phospholipids contain both hydrophobic and hydrophilic regions, which allows them to:
act as emulsifiers
stroke
"brain attack" can happen when a clot blocks an artery in the brain, and brain cells die because they don't get proper nourishment
To meet the 2010 Dietary Guidelines for Americans recommendation for fat intake, an individual should:
Balance intake of low-fat and high-fat foods Emphasize food such as fish, nuts, and vegetable oils
Rank the following to describe the transformation of triglycerides when energy is needed.
Adipose cells break down triglycerides into fatty acids and glycerol molecules Fatty acids and glycerol are released into the bloodstream Cells remove fatty acids from the blood and the liver removes glycerol form the blood Cells metabolize fatty acids for energy and liver converts glycerol into glucose for energy
What removes fatty acids and glycerol from the bloodstream and reassemble them into fat for storage?
adipose cells
Outline the process of enterohepatic circulation beginning with bile salts absorbed in the small intestine.
Bile salts are absorbed in the ileum of the small intestine Bile salt travels through the blood to the liver The liver recycles used bile salts to make new bile
Why is it important to have fat in your diet and in the body?
Fat provides insulation Fat maintains cell membranes Fat cushions organs
A heart heathy diet emphasizes what?
Foods that are good sources of polyunsaturated FAs and monounsaturated FAs, such as fish, nuts and vegetable oils
What can you replace food that's rich with saturated fats with to reduce risk of CVD?
Foods with polyunsaturated fatty acids.
Other risk factors for atherosclerosis:
Genetics C-reactive protein - high blood levels of C-reactive protein are indicative that inflammation is occurring in the body High levels of triglycerides - especially for women Sleep apnea Emotional stress Alcohol
The lipoprotein that contains the highest amount of protein is:
HDL (high-density lipoproteins)
What are some risk factors for CVD?
Physical inactivity insulin resistance
Select all of the following dietary changes that will most likely lower the risk of atherosclerosis development.
Reducing consumption of saturated fat to less than 7% of total calories and trans fats to less than 1% of total calories Ensuring that polyunsaturated fat intake is around 10% of total calories Maintaining total dietary fat intake at no more than 35% of total calories
Which products contain high amounts of saturated fat?
Sausage, palm oil, and cheese
10-12 hours after a meal, most chylomicrons have been reduced to small, cholesterol-rich particles. What does the liver do with these particles?
The liver clears these particles from the bloodstream and uses their contents to produce various substances, including very-low-density lipoprotein (VLDL), which carries a high proportion of lipids in the bloodstream
What happens when plaque or a clot completely blocks blood flow to a section of the heart muscle?
The tissue dies and a heart attack occurs
A phospholipid is chemically similar to ______, except that one of the fatty acids is replaced by chemical groups that contain phosphorus and, often, nitrogen.
Triglycerides
Which organs does hypertension damage? What other problems could it cause?
heart, kidneys, brain and eyes high bp can tear or burst hardened arteries, causing serous bleeding problems or even sudden death depending on the size and location of the artery
The lipoprotein that contains the highest amount of protein is?
high-density lipoprotein
The process of _____ creates trans fatty acids which are less likely to become rancid.
hydrogenation
What can contribute to the development of hypertension?
inflexible arteries that cause abnormally high blood pressure that persists even when a person is relaxed
During digestion, fats move into the small intestine in the form of chyme where they are broken down by the enzyme?
lipase
What enzyme breaks down triglycerides into free fatty acids and glycerol in the bloodstream?
lipase
triglyceride
lipid that has 3 fatty acids attached to a 3-carbon compound called glycerol
arterial plaque
lipid-filled patch that builds up within the wall of an artery
micelle
lipid-rich particle that is surrounded by bile salts; transports lipids to absorptive cells
low-density lipoprotein (LDL)
lipoprotein that carries cholesterol to tissues
very-low-density lipoprotein (VLDL)
lipoprotein that transports a high proportion of lipids in the bloodstream
high-density lipoprotein (HDL)
lipoprotein that transports cholesterol away from tissues and to the liver, where it can be eliminated
VLDL is produced in the:
liver
___________ fatty acids can be synthesized by the body and do not need to be supplied by the diet.
nonessential
Linoleic acid
omega-6 fatty acid
Free radicals that come in contact with LDL causes the molecule to become
oxidized
When blood vessels that carry blood to all tissues except to the heart or brain have atherosclerotic plaques, the condition is called:
peripheral vascular disease
What prevents separation of compounds in foods?
phospholipids, emulsifier
Where are phospholipids found naturally?
plant and animal foods
A lipid with carbons arranged in a ring is called
sterol
alcohol
stimulated triglyceride synthesis, which can result in storage of excess triglycerides in adipose tissue
Alcohol
stimulates triglycerides synthesis, which can result in storage of excess triglycerides in adipose tissue
