Lipids Flashcards
(109 cards)
1
Q
What does it mean for a molecule to be hydrophilic/Lipophobic?
A
Water loving, polar molecule
2
Q
What does it mean for a molecule to be hydrophobic/lipophilic?
A
Water fearing, nonpolar
3
Q
What kind of molecule/structure are phospholipids? (Hydrophobic and/or hydrophilic)
A
Amphipathic- hydrophilic and hydrophobic parts
4
Q
What common lipids are “simple”?
A
Saturated FA, Unsaturated FA, glycerides (MAG, DAG, TAG), and neutral fats
5
Q
What common lipids are “complex”?
A
Phospholipids, glycolipids, lipoproteins, and sphingolipids/sphingoglycolipids
6
Q
What common lipids are “derived”?
A
Steroids, Eicosanoids, and Fat soluble vitamins
7
Q
What are the fat soluble vitamins?
A
A, D, E, K
8
Q
What are the building blocks of lipids?
A
Fatty acids
9
Q
How are fatty acids transported to tissue?
A
Fatty acids are transported via albumin
10
Q
What are the hormone precursors?
A
Prostaglandins
11
Q
What is the main storage/energy reserve for fatty acids?
A
TAGs stored in white adipose tissue
12
Q
How are free fatty acids transported in blood?
A
Albumin
13
Q
More than 90% of fatty acids found in plasma are found in what form?
A
Fatty acid esters (primarily TAG, cholesteryl esters and phospholipids)
14
Q
What fats have double bonds?
A
Unsaturated
15
Q
What types of fat play an important role in the structure of the plasma membrane?
A
Unsaturated fatty acids
16
Q
If additional double bonds were added to the structure, what happens to the melting point?
A
The melting point would decrease
17
Q
In terms of nomenclature what is C1 considered?
A
Carbonyl carbon
18
Q
Carbon 2 is also known as what? What is it attached to?
A
Alpha-Carbon, attaches to carboxyl group
19
Q
Carbon 3 is the….
A
Beta-Carbon
20
Q
Carbon 4 is the…
A
Gamma-Carbon (y-carbon)
21
Q
What is w-carbon (omega-carbon) attached to?
A
A methyl group
22
Q
Double bonds in a fatty acid can also be named using what as reference?
A
w-carbon
23
Q
Arachidonic acid can also be referred to as what? Why?
A
w-6 fatty acid, because the first double bond is 6 carbons from the omega(w) end.
24
Q
Where can VLCFA be found?
A
In the brain
25
What is the precursor for arachidonic acid?
Linoleic acid
26
Linoleic acid is also known as what acid?
w-6 fatty acid
27
Linoleic acid is the substrate for what synthesis?
Eicosanoids
28
alpha-Linoleic acid is also known as what?
w-3 fatty acid
29
What are alpha-linoleic acids important for?
Growth and development
30
What fatty acids are liquid at room temperature?
Unsaturated fatty acids
31
What fatty acids are solid at room temperature?
Saturated fatty acids
32
Both unsaturated and saturated fatty acids are composed of what?
TAG
33
Does cis-formation have a high or low melting point? Explain.
Low melting point because it has higher energy, it's more polar and less symmetric, so it is less tightly packed making it easier to break down.
34
Does trans-formation have a high or low melting point? Explain.
High melting point because it is lower energy, less polar, more symmetric therefore more tightly packed making it harder to break down.
35
Consumption of what fats shows elevated risk for coronary artery disease?
Trans fats
36
What do trans fats do to LDL and HDL cholesterol?
Increases LDL (bad cholesterol) and decreases HDL (good cholesterol)
37
What makes phospholipids amphipathic?
Hydrophilic head and hydrophobic tail
38
What is the backbone in phospholipids?
Glycerol
39
What are the main lipids of of cell membranes?
Phospholipids
40
True or false
Membrane phospholipids are important in lung sulfactants and detergents such as bile
False - non-membrane phospholipids
41
What are the two classes of phospholipids that are essential for membranes and cell signaling?
Glycerophospholipids and Sphingophospholipids
42
What is the main sphingophospholipid?
Sphingomyelin
43
What is sphingomyelin important for?
Myelin sheath for nerves
44
Cardiolipin is a component of what portion of the mitochondria?
Inner membrane
45
What cells can NOT synthesize phospholipids?
Erythrocytes
46
What are synthesized from cell cystolic precursors (fatty acetyl coA and glycerol 3 phosphate)?
Glycerophospholipids
47
Where does synthesis of phospholipids occur?
Smooth ER
48
What converts phosphatidic acid to diacylglycerol?
Phosphatase
49
Where are phospholipases found?
Toxins and venoms, all tissues and pancreatic juice
50
Many pathogenic bacteria produce these enzymes to dissolve cell membranes and facilitate infection.
Phospholipases
51
Glycosphinglolipids contain carbohydrates and are derived from what?
Ceramides (LCFA attached to sphingosine)
52
Unlike phospholipids, glycosphingolipids do not contain what?
Phosphate
53
Where are glycosphingolipids found in the highest concentration?
Nerve tissue
54
Glycosphingolipids are important for regulation of?
Growth and development
55
What blood type has neither GalNac or Gal?
Blood type O
56
What blood type has a terminal sugar on GalNac?
Blood type A
57
What blood type has a terminal sugar on the gal?
Blood type B
58
What roles do Eicosanoids play?
-Gastric integrity
-renal function
-Smooth muscle contraction
-blood vessel diameter
-Platelet homeostasis
-Inflammation response
59
What mediates the biologic actions of Eicosanoids?
Plasma membrane G-protein coupled receptors
60
What are the three main Eicosanoids?
Prostaglandins, Thromboxanes, Leukotrienes
61
Cholesterol is hydrophilic or hydrophobic?
Hydrophobic
62
What lipid consists of 4 fused hydrocarbon rings?
Cholesterol
63
True or False
Cholesterol can only be taken in through diet.
False. Diet AND synthesized in the body
64
What is the structural component of all cell membranes (modulating fluidity)?
Cholesterol
65
Most plasma cholesterol is in what form?
Esterfied form
66
Because cholesteryl esters are more hydrophobic than cholesterol what do they need for transport?
Lipoproteins
67
What is the structural component of cell membranes and lipoproteins?
Cholesterol
68
Cholesterol is the precursor to what 3 things?
Bile acid
Steroid hormones
Vitamin D
69
What is the center of control for cholesterol homeostasis?
Liver
70
Because of hydrophobicity what must cholesterol be attached to?
Plasma proteins (i.e albumin)
71
What are the plasma lipoproteins?
Chylomicrons, VLDL, LDL and HDL lipoproteins
72
Where do abnormalities in lipoprotein metabolism generally occur?
Site of production or site of destruction (utilization)
73
What is the precursor for cardiolipin?
Phosphatidylglycerol (PG)
74
What is the cardiolipin a component of and what is important for?
Inner mitochondrial membrane, relevant for maintenance of the ETC complexes.
75
What do PAF's do?
Activate inflammatory cells, platelet aggregation, hypersensitivity and anaphylactic reactions
76
What are the only cells that can not synthesize phospholipids?
Erythrocytes
77
Glycosphingolipids contain carbohydrate and are derivatives of what?
Ceramides
78
Where are VLDL's produced?
Liver
79
What are VLDL's predominantly composed of and what are their function?
They are composed of endogenous TAG, functioning to carry lipids from the liver to the peripheral tissues where TAG is then degraded.
80
LDL have high concentrations of what?
Cholesterol and cholesteryl esters
81
What is the function of LDL?
To deliver cholesterol to the peripheral tissues, or return it to the liver.
82
What is the function of HDL?
It delivers cholesterol from the peripheral tissues to the liver to be eliminated from the body.
83
What enzyme is important for lipid digestion in infants?
Acid lipases
84
What is the main organ for synthesis and secretion of lipase?
Pancreas
85
Where are bile salts synthesized and stored?
Synthesized in the liver, stored in the gall bladder
86
Bile salts are amphipathic derivatives of what?
Cholesterol
87
TAG is hydrolyzed by what enzymes?
Pancreatic lipase and co-lipase
88
Cholesteryl ester (CE) is hydrolyzed by what enzyme?
Cholesterol esterase
89
Pancreatic juice is rich in what enzyme?
Phospholipases
90
The end products of hydrolytic lipid digestion combine with bile salts to form what?
Mixed Micelles
91
Micelles are directly absorbed from what?
Enterocytes
92
What fatty acids are taken directly by the enterocyte membrane without the aid of the mixed micelle?
Short and medium chain
93
Mixed micelles are formed from what?
Bile salts and lipid soluble vitamins (ADEK)
94
Lipoprotein for lipid transport
Chylomicron
95
Re-esterified lipids, cholesterol, and protein are packed into the Golgi Apparatus into what structure?
Chylomicron
96
CCK stimulates what?
Secretin
97
What gets bile from the gall bladder for excretion?
CCK
98
Does CCK decrease or increase GI motility? Why?
Decreases GI motility to allow for more time for digestion.
99
What cells produce CCK?
I-cells
100
What cells produce Secretin?
S-cells
101
List the 3 precursors for Gluconeogenesis
1. Amino acids
2. Glycerol
3. Lactate
102
What converts lactate to pyruvate in the Cori cycle?
LDH
103
What are the 3 steps involved in Glycogenesis?
1. Glycogenin primes
2. Glycogen synthesis adds to chain
3. Branching enzymes create the double bonds
104
What does insulin do to glycogenesis and glycogenolysis?
It stimulates glycogenesis and inhibits glycogenolysis
105
Is insulin anabolic or catabolic?
Anabolic because it is increasing glucogenesis
106
Glucagon does what to glycogenesis and glycogenolysis?
Stimulates glycogenolysis and inhibits glycogenesis
107
Is glucagon anabolic or catabolic?
Catabolic because it is breaking things down.
108
What does glycogenesis create?
Glycogen
109
What does glycogenolysis do?
Breaks down glycogen
