chap 6 Flashcards
1
Q
types of lipids
A
fatty acid, triglycerides, phospholipids, cholesterol
2
Q
lipids generally ____ in water
A
insoluble
3
Q
fatty acids are ___ dense than water
A
less
4
Q
major functions of lipids in the body
A
provide, store energy
maintain cell membrane
produce certain hormones
insulate and cushion the body
absorb and store fat-soluble vitamins and phytochemicals
contribute to foods
5
Q
lipid contribution to food
A
rich flavor, smooth texture, appetizing aroma
6
Q
fatty acid
A
contain hydrocarbon chain with an omega group (methyl, CH3) at one end, and an acid group (COOH) at the other
7
Q
short chain fatty acid
A
2-4 carbon
8
Q
medium chain fatty acid
A
6-12 carbon
9
Q
long chain fatty acid
A
14-24 carbon
10
Q
saturated fatty acid
A
each carbon atom is completely filled with hydrogen
11
Q
unsaturated fatty acid
A
missing hydrogen atoms, molecule has one or more double bonds in the carbon chain
12
Q
monounsaturated
A
only one double bond within the carbon chain
13
Q
polyunsaturated
A
two or more double bonds within the chain
14
Q
how to get omega number
A
count carbons from one omega end and the number is where the double bond occurs
15
Q
difference between fats and oils
A
fats are solid at room temp and most oils are liquid
16
Q
foods that are rich sources of long chain fatty acids tend to be more ____ at room temp than foods with larger amounts of unsaturated
A
solid
17
Q
two essential fatty acids
A
omega-3 and omega-6
18
Q
alpha-linoleic acid
A
omega 3
19
Q
linoleic acid
A
omega-6
20
Q
which omega essential fatty acid is not as prevalent
A
omega 3
21
Q
DHA made from
A
omega 3, alpha-linoleic
22
Q
EPA made from
A
omega 3, alpha-linoleic
23
Q
arachidonic (AA) made from
A
linoleic acid, omega 6
24
Q
fatty acid deficiency is uncommon in the US because
A
americans consume large amounts of fat
25
signs of essential fatty acid deficiency
scaly skin, hair loss, poor wound healing
26
infants with essential fatty acid deficiency experience
poor nervous system development, do not grow
27
trans fat
unsaturated fatty acids with the hydrogens of double bonded carbons on opposite sides of the molecule rather than the same side
28
few foods naturally contain trans fat
meat, some dairy
29
partial hydrogenation (PHOs)
food manufacturing process that added hydrogen atoms to some unsaturated fatty acids in a liquid vegetable oils
30
PHOs convert natural cis fatty acids to
trans fatty acids
31
PHO structure
similar to saturated
more solid at room temp
32
PHOs are ___likely to undergo oxidation
less
33
PHOs can cause
increase heart disease risk
34
the FDA determined PHOs are
dangerous, banned
35
triglyceride
3 fatty acids attached to a glycerol backbone
36
about 95% of lipids in the body and in foods are in the form of
triglycerides
37
saturated fat food sources
beef, butter, cream, whole and reduced-fat dairy, coconut
38
monounsaturated fat food sources
avocados, olives, peanuts, pumpkin and sesame seeds, almonds, hazelnuts, pecans, fish
39
polyunsaturated fat food sources
walnuts, flaxseed, fish
40
trans fat food sources
beef, milk, other dairy
41
phospholipids are chemically similar to triglyceride except
one fatty acid is replaced by a compound that contains phosphorus and often nitrogen
42
phospholipids contains ____ tail and ____ head
hydrophobic, hydrophilic
43
phospholipids found naturally in
plant and animal foods
44
major phospholipid in food
lecithin
45
rich sources of lecithin
egg yolk, liver, wheat germ, peanut butter, soybean
46
lecithin contains ____
choline
47
choline
compound that nerves use to produce acetylcholine
48
eggs are often used in cooking for their
emulsifying ability
49
phospholipids act as emulsifiers because of
hydrophobic and hydrophilic ends
50
emulsifiers
substances that keep water soluble and water insoluble compounds mixed together
51
___ foods often have emulsifying agents added
processed
52
lipid major structural component of cell membrane
double layer of phospholipids allows membrane flexibility
53
sterol
carbons arranged in rings, which makes them a more chemically complex type of liquid than a triglyceride or phospholipid
54
most known sterol
cholesterol
55
cholesterol only found in
animal foods
56
common sources of cholesterol
egg yolk, liver, meat, poultry, whole mill, cheese, ice cream
57
the body produces and uses cholesterol to make
vitamin d
steroid hormones
bile
58
plant sterol and stanols are not ____ by humans
absorbed
59
plant sterol and stanols compete with ____ for absorption
cholesterol
60
how are blood cholesterol levels decreased with plant sterols and stanols
they compete with each other and the plant sterol and stanols will be absorbed more than the cholesterol
61
best sources of plant sterol/stanols
nuts, seeds, legumes
62
some fat digestion occurs due to the action of
salivary lipase and gastric lipase
63
primary site of lipid digestion
small intestine
64
fatty chyme in the small intestine stimulates release of
cholecystokinin (CCK)
65
CCK signals the gallbladder to
release bile
66
CCK stimulates the pancreas to
release digestive enzymes, including pancreatic lipase
67
bile contains ____ which aid in digestion and absorption
bile salts
68
bile salts have ____ heads and ____ tails and surround lipid particles to form ____
hydrophilic, hydrophobic, micelles
69
micelles
transport lipids to absorptive cells
70
action of bile salts increase the surface area of lipids available to
pancreatic lipase, aids in digestion
71
pancreatic lipase
removes two fatty acids from a triglyceride, forming a monoglyceride, also produces some FFA and glycerol
72
phospholipids digested by
phospholipase, removes two FA
73
cholesterol does not undergo
digestion
74
end product of lipid digestion
glycerol, FFA, monoglycerides, phospholipid fragments
75
lipid absorption: micelles transport end products of lipid digestion to the villi in the ____
small intestine
76
short and medium chain fatty acids directly enter the
portal bloodstream
77
absorptive cells of the small intestine form ____ with other end products of lipid digestion
chylomicrons
78
chylomicrons
lipoproteins
79
lipoprotein
water soluble structures that transport lipids through the bloodstream
80
chylomicrons travel through the ___ system to the thoracic duct where they enter the blood stream
lymphatic
81
lipoprotein lipase
enzyme capillary walls that break down triglyceride from chylomicrons as they move into the body
82
stomach lipid digestion/absorption
minor digestion of fat by salivary and gastric lipases
83
liver lipid digestion/absorption
liver produces bile, which is stored in the gallbladder and released into small intestine. bile aids in lipid digestion and absorption by emulsifying lipids in digestive juices
84
pancreas lipid digestion/absorption
secretes a mixture of enzymes, including pancreatic lipase into sm intestine
85
small intestine lipid digestion/absorption
primary site
86
____% of undigested fat is normally excreted in the feces
<5
87
most used bile salts are absorbed in the
small intestine ileum
88
the liver recycles used bile salts to make
new bile
89
eating food that contains ___ fiber can interfere with bile salt recycling
soluble
90
without a supply of recycled bile salt
the liver has to remove cholesterol from the bloodstream to make new bile salts, blood cholesterol levels drop
91
adipose cells remove ___ and ___ from circulation and reassemble into ____ for storage
glycerol, FFA, triglycerides
92
cells remove ____ from the bloodstream and metabolic them for energy
Fatty acids
93
liver removes ____ molecules and converts them to ____
glycerol, glucose
94
AMDR for fat
20-35%
95
saturated fat should be ___%
<10
96
lipid information required on label
total fat
sat fat
trans fat
cholesterol
97
CVD
group of medical conditions that affect the functioning of the heart and blood vessels
98
coronary artery disease
affects the arteries that supply the heart, often leading to heart attack
99
cardiovascular diseases
CAD, PAD, stroke, hypertension
100
____ and ___ are among the top 5 leading causes of death
CAD, stroke
101
atherosclerosis
long term disease process in which plaque builds up inside arteries
102
atherosclerosis initiated by
excess cholesterol or glucose in the bloodstream, compounds from smoke, bacteria
103
atherosclerosis leads to formation of
arterial plaque
104
arterial plaque may result in the formation of
thrombus
105
thrombus
fixed bunch of blood clots that remain in place and disrupt flood flow
106
a healthy artery has ___ lining
smooth
107
when the lining of the artery become irritated, certain cells within the wall deposit _____ and other substances under the lining to repair damage
cholesterol
108
plaque ___ and ___ the normally smooth surface, which ___ blood flow, making ___ more likely to form ____
narrows, roughens, slows, clots
109
if a clot lodges on the plaque and becomes wedged,
blood flow can become blocked completely
110
embolus
thrombus or part of a plaque that breaks free and travels through the bloodstream
111
a thrombus or embolus can completely block flood flow leading to
heart attack
stroke
gangrene
112
atherosclerosis in the carotid artery in the neck can
increase risk for stroke
113
atherosclerosis and hypertension
affected arteries thicken and lose flexibility
114
lipoproteins transport
lipids in the blood
115
lipoproteins play a major role in
the development of atherosclerosis
116
4 major types of lipoproteins
VLDL, HDL, LDL, chylomicron
117
____ content contributes to the density of a lipoprotein
protein
118
chylomicron ___% protein
1-2
119
HDL ___% protein
45-60
120
LDL ___% protein
25
121
VLDL ___% protein
5-10
122
HDL
good cholesterol
123
HDL transports cholesterol ____ tissues and ___ liver, where it can be eliminated ______ contribute to plaque formation
away, to, does not
124
LDL
bad cholesterol
125
LDL carries cholesterol ___ tissues, _____contribute to plaque formation
to, does
126
VLDL carries much of the ____ in the bloodstream
triglycerides
127
high levels of VLDL may contribute to
atherosclerosis
128
major risk factors for atherosclerosis
age, genetics
unhealthy diet, HTN, diabetes, elevated cholesterol (LDL), excess body fat, physical inactivity, tobacco use
129
when we absorb fat where does it go
lacteals/lymphatic system
