Lipids (midterm) Flashcards

1
Q

What is the monomer of lipids?

A

TGs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

FAs are rarely free in nature, they are usually linked to other molecules by their….

A

hydrophilic carboxylic acid group

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

FAs primarily exist as….

A

unbranched hydrocarbon chains

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How are FAs classified?

A

1) number of carbons
2) number of double bonds
3) position of the last double bond in the chain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are SCFAs found in?

A

-breast milk
-coconut oil
-dietary soluble fiber

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

SCFAs have how many carbons?

A

less than 6 carbons

ex:
-acetate has 2 C
-propionate has 3C
-butyate has 4 C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

MCFAs have how many carbons?

A

6-12 carbons

ex: lauric acid has 12 C

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

T/F: MCFAs need bile for absorption

A

false

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

MCFAs is found in what oil?

A

coconut (also has SCFAs in there)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the 2 health benefits of MCFAs?

A

-facilitates weight loss
-can treat neurodegenerative diseases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Most FAs in nature are- SCFAs, MCFAs, or LCFAs?

A

LCFAs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How many carbons are there in LCFAs?

A

12+ carbons

ex: palmitate has 16 carbons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are the 2 subclasses for LCFAs?

A

MUFAs (omega 9) and PUFAs (omega 3 and 6)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the 3 health benefits of SCFAs?

A

-good for baby
-keeps colon cells healthy
-keeps gut flora healthy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What does a saturated FA structure look like?

A

no double bonds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Are saturated FAs usually short or long?

A

long

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Are saturated FAs usually solid or liquid at room temp?

A

SOLID (some are liquid like palm oil and coconut oil, but butter, lard, and animal fat are solid)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Which FAs have a higher melting and smoke point?

A

saturated FAs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What food has saturated FAs?

A

-butter, lard, animal fat
-palm oil
-coconut oil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Saturated fats in general are associated with increased serum _____________ levels and higher _______

A

cholesterol, LDLs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What does an unsaturated FA structure look like?

A

with double bond (if carbons are on same side = cis double bond, if opposite sides then its a trans double bond)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Are MUFAs liquid or solid at room temp?

test q

A

liquid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Are MUFAs liquid or solid in the refrigerator?

test q

A

solid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

oleate has what omega classification?

A

omega 9

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Oleate is extracted from which oil?

A

olive oil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Which FA has lower smoke points and is not good for high heat cooking methods such as frying?

A

MUFAs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What are some examples of MUFA food sources?

test q

A

-olive oil
-canola oil
-safflower oil
-peanut oil
-most nuts in general
-avocado

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

If you burn oil and it smokes then it will make carcinogens and release it into your food. How do you prevent this?

A

add oil and food at the same time so that the food will absorb the oil rather than heating the oil first and getting overheated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Which FA is liquid at room temp and refrigerator?

A

PUFA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Which omega classifications are PUFAs?

A

omega 3 and 6 FAs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What are the 2 important PUFAs that are essential?

A

1) linoleic acid (18:2, omega 6)
2) alpha linolenic acid (18:3, omega 3)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

How many carbons and double bonds are there in linoleic acid?

A

18:2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is the omega classification for linoleic acid?

A

omega 6

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

How many carbons and double bonds are there for alpha linolenic acid?

A

18:3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is the omega classification for linolenic acid?

A

omega 3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Which omega class should we try to eat the most?

A

omega 3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What foods have omega 3 FAs?

A

-salmon
-tuna
-herring
-mackerel
-cod liver oil
-flaxseeds
-walnuts
-wheat germ oil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Eicosapentanoic acid (EPA) 20:5 and docosahexaenoic acid (DHA) 22:6 are related. Both of these are metabolized to form….

A

omega 3 eicosanoids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What is the recommended intake of fish per week?

A

2x a week

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Human brains and CNS cell membranes require ___________ for optimal function

A

EPA/DHA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Increased omega 3 FA in the diet is associated with:

A

-decreased incidence of cardiovascular disease
-decreased plasma TG levels
-decreased inflammatory disorders
-decreased symptoms of RA
-decreased severity of asthma in children
-improved lung function in people with cystic fibrosis
-decreased severity of symptoms in psychiatric disorders like schizophrenia and depression
-decreased incidence of colon, breast, prostate, and lung cancers
-decreases symptoms of ADHD in children

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Omega 6 FA is found in what foods?

A

veggie oil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

How much veggie oil (omega 6 FA) should you consume a day?

A

1 tablespoon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Arachidonic acid 20:4 can be made from omega 6 linoleic acid. Arachidonic acid is considered conditionally essential. It is metabolized to form….

A

omega 6 eicosanoids like prostaglandins, thromboxanes, and leukotrienes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Eicosanoids are made when released by what enzyme?

A

phospholipase A2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Eicosanoids mediate what?

A

-pain sensation
-immune function
-vasodilation/constriction
-inflammation
-blood clotting
-muscle contraction
-short term memory
-intestinal motility

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Aspirin is an irreversible inhibitor of?

A

cyclooxygenase (COX 1 and 2, aka prostaglandin and thromboxane)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

What is the function of omega 6 eicosanoids like arachidonic acid?

A

-increase blood clotting
-increase inflammatory responses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

What is the function of omega 3 eicosanoids like DHA and EPA?

A

-decrease blood clotting
-reduce risk of heart attack

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

T/F: almost all cells in the body are capable of producing eicosanoids

A

true

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

T/F: all eicosanoids have the same effect on different tissues

A

false

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

What percentage of Americans are deficient in essential FAs?

A

60%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What are the signs and symptoms of essential FA deficiency?

A

-flakey, itchy, dry skin
-dry hair
-infections
-impaired vision
-reduced learning
-hyperactivity in kids
-memory problems
-allergies
-inflammatory diseases
-depression
-violence
-heart disease
-arthritis
-soft nails
-polydipsia (excessive thirst)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Which oil is the highest in saturated fat?

test q

A

coconut oil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

Which oil is the highest in MUFAs (omega 9 oleic acid)?

test q

A

safflower oil and olive oil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

Which oil is the highest in alpha linolenic acid (omega 3, PUFA)?

A

flaxseed oil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

Which oil is the highest in linoleic acid (omega 6, PUFA)?

A

sunflower oil

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

What is hydrogenation of FAs?

A

-process is used to solidify an oil to increase the melting temp
-addition of H to carbon double bonds
-formation of trans FA, which increases shelf life

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

What foods are high in trans FAs?

A

-hydrogenated fats
-deep fried food
-high fat baked goods
-non-diary creamers
-salty snacks
-commercial cakes, cookies, and other baked goods

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

Excessive trans fat intake raises _______ and lower _______

A

LDL, HDL

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

Excessive trans fat intake increases risk for what disease?

A

heart disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

How much cholesterol should we consume a day?

A

200-300 mg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

Low fat diet is not recommended for who?

A

children under 2 y/o

64
Q

Which FAs emulsify food during digestion?

A

MG and DGs

65
Q

What is the most efficient energy storage?

A

TGs

66
Q

Hydrolysis of 2 monoglyceride results in:

A

1 glycerol + 1 FA

67
Q

What are the simple lipids?

A

-MG, DG, TGs
-waxes (esters of FAs w/ high molecular weight alcohols)

68
Q

What are the compound lipids?

A

-phospholipids
-sphingolipids
-lipoproteins

69
Q

What makes up a phospholipid?

A

-glycerol backbone
-phosphoric acid
-2 FAs

70
Q

What is the key source of intracellular signaling agents (eicosanoids, inositol, and choline)?

test q

A

phospholipids

71
Q

What makes up a sphingolipid?

A

-sphingosine backbone
-1 FA
-polar head group

ex of sphingolipids:
-ceramide
-sphingomyelins
-gangliosides
-cerebrosides

72
Q

Sterols and steroids come from where?

A

-cholesterol (animal products)
-plant sterols (5% of dietary lipids, can block bile and cholesterol absorption)

73
Q

What are the functions of sterols and steroids?

A

-membrane and lipoprotein component (cholesterol)
-hormones (precursors for vit D, estrogen, and progesterone)
-bile salts (solubilize lipids during digestion)

74
Q

Which 2 molecules are completely hydrophobic?

A

TGs and cholesterol ester

75
Q

How do we degrade hydrophobic molecules in a hydrophilic environment?

A

emulsify lipids with bile salts

76
Q

Are there any lipid digestion enzymes in the mouth? If so, what are they?

A

-lingual lipase aka gastric lipase
-important largely for infants
-acts on breast milk fats (short-medium chain length FAs)

77
Q

Are there any lipid digestion enzymes in the stomach? If so, what are they?

A

none

78
Q

What slows the release of food from the stomach?

A

fat

79
Q

Which part of the body performs 90% of all lipid digestion?

A

SI

80
Q

When lipid rich chyme enters the duodenum, the gallbladder is stimulated by CCK to release bile acids. The SI mixes bile salts to convert lipid emulsion into __________. The SI primarily performs __________ and _________________

A

micelles, hydrolysis, de-esterification

81
Q

Enzymes for lipid digestion are secreted from the ____________ and are stimulated by ________

A

pancreas, CCK

82
Q

Which digestive enzymes help break down lipids and are secreted from the pancreas?

A

-pancreatic lipase + colipase
-phospholipase A2
-cholesterol esterase

83
Q

Pancreatic lipase and colipase act on the 1st and 3rd position of _______

A

TGs

84
Q

Phospholipase A2 acts on the ______ position of phospholipid

A

2nd

85
Q

Once phospholipids are cleaved at C2, what enzyme comes in next to break it down more?

A

lecithinase

86
Q

What is the function of cholesterol esterase in low pH environment (usually in lumen)?

A

will remove FA from cholesterol ester to make cholesterol + FA

87
Q

What is the function of cholesterol esterase in high pH environment (usually the mucosa)?

A

will add FA to cholesterol to make cholesterol ester

88
Q

Dietary lipids must be de-esterified into free FA and MG and cholesterol to get into the mucosal cell (TGs and cholesterol esters are too large for movement across cell membranes). The lipids are packaged as _________________ in the mucosal cells and enter into circulation via the lymphatics and _______________

test q

A

chylomicrons, L subclavian v.

89
Q

What does “apo” mean?

A

protein part of apolipoprotein

90
Q

Chylomicron and chylomicron remnants are made in the _______ with dietary lipids 1-2 hours after eating a high fat diet. Blood will look milky from the high fat

A

SI

91
Q

What are the bad (non-HDL) lipoproteins?

test q

A

1) chylomicron and chylomicron remnant
2) VLDL (very low density lipoprotein)
3) IDL (intermediate density lipoprotein)
4) LDL (low density lipoprotein)

92
Q

What is the good lipoprotein?

test q

A

HDL (high density lipoprotein)

93
Q

What are apolipoproteins?

A

-the protein component of lipoproteins
-stabilize lipoproteins as they circulate thru the vasculature
-confer specificity allow for recognition by other lipoproteins and cell receptors
-designated by series of letters A-E

94
Q

What is the largest and least dense of lipoproteins?

A

chylomicrons

95
Q

chylomicrons transport….

test q

A

dietary lipids (primarily TGs and cholesterol ester from the SI to the rest of the body via lymphatics)

96
Q

Chylomicrons obtain apolipoprotein _______ within the enterocytes, unique to the chylomicrons

test q

A

B48

note: this is a marker that can be seen in blood work

97
Q

Chylomicrons obtain apo ______ and _______ from HDLs once they reach the blood

test q

A

C2, E

98
Q

Is apo B48 an integral or peripheral protein?

A

integral

99
Q

Are apo C2 and E integral or peripheral proteins?

A

peripheral proteins

100
Q

Chylomicrons decrease in size as they deliver dietary TGs to peripheral tissues. At this point, _________ is returned to HDL

A

apo C2

101
Q

Chylomicron remnants are recognized by receptors on membranes of the liver via ____________ and removed, disassembled and repackaged into ______

A

apo B48 and E, VLDL

102
Q

Apo C2 is found where?

A

peripherally on chylomicrons, VLDL, and HDL

103
Q

Which apolipoprotein is the activator of lipoprotein lipase (breaks down TGs in chylomicrons) found on endothelial vessel walls lining tissues such as adipose and muscle?

A

apo C2

(this releases the FAs from TGs in chylomicrons/VLDL for cellular uptake and usage as either energy (muscle) of storage (adipocytes)

104
Q

T/F: dietary fat is directly dumped into adipocytes if the body is getting enough energy from protein intake

A

true

105
Q

Chylomicrons will shrink after products are released. What apoproteins are still there?

A

B48 and E

106
Q

Chylomicron remnant enters liver cells via what transport process?

A

receptor mediated endocytosis (and then it will be broken down by lysosome)

107
Q

Very low density lipoproteins are generated where?

A

from liver

108
Q

The liver takes the remaining lipid from the chylomicron remnants by receptor mediated endocytosis, along with other lipids generated from the liver and repackages them into _________

A

VLDLs

109
Q

VLDLs obtain apo _____ in the liver

test q

A

B100

110
Q

VLDLs obtain apo ________ from HDLs in the blood

A

C2 and E

111
Q

As VLDLs travel thru the body, cells remove TG causing the VLDL to shrink. This alters the proportion of lipids, and the lipoprotein becomes denser. The remaining VLDL mutates into an _______, then ________, and then returns apo C2 and E back to the HDLs

A

IDL, LDL

112
Q

What apolipoproteins does IDL have? What is the difference between VLDLs?

A

-same apo as VLDLs, so apo B100, C2, and E
-difference is the size, IDL is smaller and cholesterol stays

113
Q

What apolipoproteins does LDL have? How is this different from IDL?

A

-IDL has the same apo as VLDLs but LDL has shrunk even more so it only has B100
-cholesterol is still here just like with IDL and VLDLs, but the cholesterol conc. increases here bc the lipoprotein has gotten much smaller and denser

114
Q

Macrophages can breakdown proteins and phospholipids but NOT ______________

A

cholesterol

115
Q

LDLs have a high conc. of _________ and low conc. of _____

A

chol, TGs

116
Q

What is the function of LDLs?

A

they circulate and make chol available to cells of all tissues
-all tissues need chol for vitamin D, hormones, etc
-“kiss and touch” can just give chol to whoever needs it
-if no tissue needs chol then it’ll just go back to liver

117
Q

Is apo B100 an integral or peripheral protein?

A

integral protein

118
Q

In the liver, special LDL receptors recognize apo B100 by removing LDLs from circulation via….

A

receptor-mediated endocytosis

119
Q

If theres too much LDL in the body, what happens?

A

bad stuff- apo B100 will get damaged and cause LDL to become oxidized, but this means it cant go back to the liver, so it will precipitate in the wall of an artery, deposit there, make foam cells and increase BP

120
Q

LDL receptors are negatively charged glycoproteins and are clustered on pits on cell membranes. The intracellular side of the pit is coated with the protein ____________, which stabilizes the pit

A

clathrin

121
Q

T/F: everyone has some LDLs and oxidized LDLs

A

true

122
Q

After gastric bypass, the body is forced to make more ______

A

HDL

123
Q

Where is HDL made?

A

in the liver and intestines

124
Q

What is the smallest lipoprotein?

A

HDL

125
Q

Which lipoprotein has the highest conc. of protein?

A

HDL

126
Q

Which apolipoprotein is unique to HDL?

test q

A

apo A

127
Q

HDL serves as a _________ for other apolipoproteins, such as apo E and C2

A

reservoir

128
Q

HDL picks up unesterified cholesterol from dying cells and other sources and esterifies the cholesterol by its enzyme…

A

phosphatidylcholine cholesterol acyltransferase (PCAT), or another name for it is lecithin cholesterol acyltransferase (LCAT)

129
Q

A phospholipid with a choline attached to the phosphohead of the 3rd carbon is called:

A

lecithin

130
Q

HDL transfers chol from other lipoproteins to the liver for…

A

recycling or disposal

131
Q

Which lipoprotein plays a key role in cholesterol homeostasis?

A

HDL

132
Q

Which lipoprotein can dissolve plaque in arteries?

A

HDL

133
Q

lecithin + cholesterol with LCAT = ?

A

lysolecithin + cholesterol ester

134
Q

What is lysolecithin?

A

-one of the products after LCAT or PCAT adds FA to cholesterol
-lysolecithin has only one tail and is a detergent
-lysolecitin can promote the liver to pick up HDL thru endocytosis

135
Q

Which organ is the ONLY organ that can process cholesterol ester?

test q

A

liver

136
Q

What is atherosclerosis?

A

-plaque build up in arteries
-plaque is mostly cholesterol but also has calcium and fibrin in it
-can start as early as childhood if they eat high chol foods frequently
-if the artery gets completely blocked with plaque then it will cause a heart attack

137
Q

Where does VLDL come from?

A

liver

138
Q

Which lipoprotein transports endogenous TGs to peripheral tissues?

A

VLDL

139
Q

Where does LDL come from?

A

IDL

140
Q

Which lipoprotein transports endogenous cholesterol to peripheral tissue?

A

LDL

141
Q

Which lipoprotein converts cholesterol to cholesterol ester and transports it back to the liver?

A

HDL

142
Q

How are FAs transported in the blood?

A

with albumin

143
Q

How are dietary TGs and chol ester transported in the blood?

A

chylmicrons

144
Q

How are endogenous TGs transported in the blood?

A

VLDL or IDL

145
Q

How is endogenous chol transported in the blood?

A

LDL

146
Q

How is endogenous chol ester transported in the blood?

A

HDL

147
Q

High _______ are associated with a high risk of heart disease whereas high _______ have a protective effect

A

LDLs, HDLs

148
Q

What should our HDL be ideally in males and females?

A

more than 40 mg/dL in males, more than 60 mg/dL in females

149
Q

What is hyperlipidemia?

A

-decreased HDL
-increased LDL and/or increased TGs

150
Q

What are the risk factors for heart disease?

A

-family hx
-smoking (increases inflammation, depletes HDL and increases ROS)
-elevated BP
-hyperlipidemia (HDL is less than 35 mg/ dL)
- high blood chol
-diabetes
-lack of regular exercise and obesity
-homocysteinemia
-c-reactive protein
-increased apo B particles

151
Q

What is homocysteinemia?

A

-associated with neuro and cardio diseases
-vitamin deficiency in B6, B9 (folic acid), and B12 is the major cause
-this causes homocysteine build up in the blood
-this is an independent risk factor for cardiovascular disease

152
Q

What should you do to reduce your risks of heart disease?

A

reduce chol levels by:
-reducing dietary saturated fat, trans fat, and chol
-reducing refined carbs
-increasing dietary fiber and folate
-increasing plant steroids and sterols

reduce oxidation and inflammation by:
-increasing plant antioxidants and phytochemicals
-moderating PUFAs and increasing MUFAs (good fats)
-increase vit B6, B9, and B12

increase HDL by:
-increasing physical activity
-adequate caloric intake to maintain a healthy weight
-moderate alcohol intake like with red wine
-nicotinic acid (vit B3)
-statins
-quit smoking
-estrogen
-weight
-exercise
-reduced high TG diet

153
Q

Which of the following is the best source of MUFAs?
A) olive oil
B) coconut oil
C) fish oil
D) flaxseed oil

A

A) olive oil

154
Q

Cholesterol is not a precursor of ____?
A) cholic acid
B) vit D
C) estrogen
D) lecithin

A

D) lecithin

155
Q

A lack of lipoprotein lipase results in:

A

An elevated level of chylomicrons following a high fat diet

156
Q

TGs are transported from intestinal cells to adipose tissues within:

A

Chylomicrons