Lipids Flashcards
1
Q
__________ known as fats provide a major way of storing chemical energy and carbon atoms in the body.
A
Lipids
2
Q
They surround and insulate vital body organs, providing protection from mechanical shock and preventing excessive loss of heat energy.
A
Fats
3
Q
These are the basic
components of cell membranes.
A
Phospholipids, glycolipids, and cholesterol
4
Q
Several cholesterol derivatives function as chemical messengers (_____________) within the body.
A
hormones
5
Q
A __________ is an organic compound found in living organisms that is insoluble (or only sparingly soluble) in water but soluble in nonpolar organic solvents.
A
lipid
6
Q
Lipids are _________ molecule, their structure are relatively large and non-polar.
A
hydrophobic
7
Q
Lipids are ____________, which means they contain both nonpolar and polar regions
A
amphipathic
8
Q
Two classifications of lipids
A
- Saponifiable
- Nonsaponifiable
9
Q
These lipids are composed of long-chain fatty acids that form esters.
A
Saponifiable lipids
10
Q
These lipids are composed of ring structures that do not form esters.
A
Nonsaponifiable lipids
11
Q
(Classifications of lipids) Ester linkages are present in _________, while it is absent in ___________.
A
saponifiable, nonsaponifiable
12
Q
The structure of these lipids are long chain fatty acids connected to a functional group of alcohol through an ester linkage.
A
Saponifiable lipids
13
Q
Two types of non-saponifiable lipids are __________ and ___________
A
- terpenes
- steroids
14
Q
____________ are made of isoprene units, and ___________ are made of 17 carbon atoms arranged in rings
A
Terpenes, steroids
15
Q
These lipids function as structural components.
A
Saponifiable
16
Q
These lipids act as biochemical compounds, storage, and structural component.
A
Non-saponifiable lipids
17
Q
Two categories of lipids
A
Simple lipids and Complex lipids
18
Q
Two simple lipids:
A
(a) Fats and oils (triacylglycerols)
(b) Waxes
19
Q
Complex (or compound) lipids:
A
(a) Phospholipids:
(b) Glycolipids
(c) Lipoproteins
(d) Other complex lipids
20
Q
Types of phospholipids
A
- Glycerophospholipids
- Sphingophospholipids
21
Q
Based on biochemical function, lipids are divided into five categories:
A
- Energy-storage lipids
- Membrane lipids
- Emulsification lipids
- Messenger lipids
- Protective-coating lipids
22
Q
(Biochemical functions) These are energy-storage lipids
A
triacylglycerols
23
Q
(Biochemical functions) These are membrane lipids
A
phospholipids, sphingoglycolipids,
and cholesterol)
24
Q
(Biochemical functions) These are emulsification lipids
A
bile acids
25
(Biochemical functions) These are messenger lipids
steroid hormones and eicosanoids
26
(Biochemical functions) These are protective-coating lipids
biological waxes
27
It is a naturally occurring monocarboxylic acid.
fatty acid
28
In terms of carbon chain length, fatty acids are characterized as
- long-chain fatty acids(C12 to C26),
- medium-chain fatty acids (C8 and C10), - short-chain fatty acids (C4 and C6).
29
They are rarely found free in nature but rather occur as part of the structure of more complex lipid molecules.
Fatty acids
30
The carbon chain of a fatty acid may or may not contain carbon–carbon double bonds. On the basis of this consideration, fatty acids are classified as:
- Saturated fatty acids (SFAs),
- monounsaturated fatty acids (MUFAs),
- Polyunsaturated fatty acids (PUFAs).
31
It is a fatty acid with a carbon chain in which all carbon–carbon bonds are single bonds.
saturated fatty acid
32
It is a fatty acid with a carbon chain in which one carbon–carbon double bond is present.
monounsaturated fatty acid
33
It is a fatty acid with a carbon chain in which two or more carbon–carbon double bonds are present. Up to six double bonds are found in them
polyunsaturated fatty acid
34
These two types of names for an 18-carbon PUFA containing cis double bonds in the and 12 positions are as follows:
- IUPAC name: cis,cis-9,12-octadecadienoic acid
- Common name: linoleic acid
35
To specify double-bond positioning within the carbon chain of an unsaturated fatty acid, the preceding notation is expanded by adding the Greek capital letter ___________ followed by one or more superscript numbers.
delta (⧊)
36
Several different “families” of unsaturated fatty acids exist. These family relationships become apparent when double-bond position is specified relative to the ___________________ end of the fatty acid carbon chain.
methyl (noncarboxyl)
37
It is an unsaturated fatty acid with its endmost double bond three carbon atoms away from its methyl end.
omega-3 fatty acid
38
It is an unsaturated fatty acid with its endmost double bond six carbon atoms away from its methyl end.
omega-6 fatty acid
39
Saturated fatty acids with structural notation of 12:0
lauric acid
40
Saturated fatty acids with structural notation of 14:0
myristic acid
41
Saturated fatty acids with structural notation of 16:0
palmitic acid
42
Saturated fatty acids with structural notation of 18:0
stearic acid
43
Saturated fatty acids with structural notation of 20:0
arachidic acid
44
Monosaturated fatty acid with structural notation 16:1(⧊ 9) w-7
palmitoleic acid
45
Monosaturated fatty acid with structural notation 18:1(⧊ 9) w-9
oleic acid
46
Polyunsaturated fatty acid with structural notation 18:2(⧊ 9,12) w-6
linoleic acid
47
Polyunsaturated fatty acid with structural notation 18:3(⧊ 9, 12, 15) w-3
linolenic acid
48
Polyunsaturated fatty acid with structural notation 20:4 (⧊5, 8, 11, 14) w-6
arachidonic acid
49
Polyunsaturated fatty acid with structural notation 20:5 (⧊5, 8, 11, 14, 17) w-3
EPA (eicosapentaenoic acid)
50
Polyunsaturated fatty acid with structural notation 22:6 (⧊5, 7, 10, 13, 16, 19) w-3
DHA (docosahexaenoic acid)
51
(Physical Properties) ___________________ for fatty acids is a direct function of carbon chain length; it decreases as carbon chain length increases.
Water solubility
52
The physical properties of fatty acids, and of lipids that contain them, are largely determined by the ____________ and __________ of unsaturation of the fatty acid carbon chain.
length and degree
53
___________ fatty acids have a slight solubility in water, while ____________ fatty acids are essentially insoluble in water.
short-chain, long-chain
54
Fatty acids are soluble in ______________ such as benzene, chloroform, and alcohol
organic solvents
55
Fatty acids are _____________ of heat.
bad conductors
56
(Physical Properties) Long chain saturated fatty acids are _______ at room temperature, while long chain unsaturated fatty acids are _______ at room temperature
solid, liquid
57
(Physical Properties) _____________ for fatty acids are strongly influenced by both carbon chain length and degree of unsaturation (number of double bonds present). As carbon chain length increases, this property increases. This trend is related to the greater surface area associated with a longer carbon chain and to the increased opportunities that this greater surface area affords for intermolecular attractions between fatty acid molecules.
Melting points
58
These are concentrated primarily in special cells (adipocytes) that are nearly filled with the material.
triacylglycerols
59
It is the body's triaclyglycerol-storing cells.
Adipocytes
60
In terms of functional groups present, triacylglycerols are triesters; meaning, ________ ester functional groups are present.
three
61
The alcohol involved in triacylglycerol formation is always ___________, a three-carbon alcohol with three hydroxyl groups.
glycerol
62
A __________________ is a triester formed from the esterification of glycerol with three identical fatty acid molecules
simple triacylglycerol
63
A __________________ is a triester formed from the esterification of glycerol with more than one kind of fatty acid molecule.
mixed triacylglycerol
64
These are naturally occurring mixtures of triacylglycerol molecules in which many different kinds of triacylglycerol molecules are present.
Fats and oils
65
What distinguishes a fat from an oil?
their physical state at room temperature
66
A fat is a triacylglycerol mixture that is a _______________ at room temperature (25C). Generally, fats are obtained from animal sources.
solid or a semi-solid
67
An oil is a triacylglycerol mixture that is a ___________ at room temperature (25oC).
liquid
68
They are composed largely of triacylglycerols in which saturated fatty acids predominate, although some unsaturated fatty acids are present. Such triacylglycerols can pack closely together because of the “linearity” of their fatty acid chains, thus causing the higher melting points associated with them.
Fats
69
They contain triacylglycerols with larger
amounts of mono- and polyunsaturated fatty acids than those in fats. Such triacylglycerols cannot pack as tightly together because of “bends” in their fatty acid chains. The result is lower melting points.
Oils
70
Fats are generally obtained from animals; hence the term ________________.
animal fat
71
They typically come from plants, although there are also that are from fish.
Oils
72
Pure fats and pure oils are ______________, _____________, and _________.
- colorless
- odorless
- tasteless.
73
It is a fatty acid needed in the human body that must be obtained from dietary sources because it cannot be synthesized within the body, in adequate amounts, from other substances.
Essential Fatty Acids
74
These are two types of essential fatty acids. When these two acids are missing from the diet, the skin reddens and becomes irritated, infections and dehydration are likely to occur, and the liver may develop abnormalities.
- linoleic acid
- linolenic acid
75
A type of essential fatty acid that is the primary member of the omega-6 acid family,
Linoleic acid
76
A type of essential fatty acid that is the primary member of the omega-3 acid family.
linolenic acid
77
PROPERTIES OF TRIACYLGLYCEROLS
1. Hydrolysis
2. Saponification
3. Rancidity
78
Triacylglycerols undergo stepwise enzymatic ____________ to finally liberate free fatty acids and glycerol. This process, catalyzed by lipases is important for digestion of fat in the gastrointestinal tract and fat mobilization from the adipose tissues.
Hydrolysis
79
The hydrolysis of triacylglycerols by alkali to produce glycerol and soaps is known as ________________.
saponification
80
___________ is the term used to represent the deterioration of fats and oils resulting in an unpleasant taste. Fats containing unsaturated fatty acids are more susceptible to this.
Rancidity
81
These are the most abundant lipids in membranes. They are major components of the plasma membrane, the outermost layer of animal cells.
Phospholipids
82
The structure of phospholipids is composed of two _______________ and a ________________.
fatty acid cchains, phosphate head
83
Part of the phospholipids that are non-polar, hydrophobic (water fearing)
Fatty acid chains
84
Part of the phospholipids that is polar and hydrophilic (water loving)
Phosphate head
85
A phospholipid is an _______________ molecule which means it has both a hydrophobic and a hydrophilic component
amphipathic
86
A ____________________ is a lipid that contains two fatty acids and a phosphate group esterified to a glycerol molecule and an alcohol esterified to the phosphate group.
glycerophospholipid
87
A ______________ is a lipid that contains both a fatty acid and a carbohydrate component attached to a sphingosine molecule. A fatty acid is attached to the sphingosine through an amide linkage, and a monosaccharide or oligosaccharide.
sphingoglycolipid
88
These are compounds that have the steroid nucleus which consists of four fused carbocyclic rings. This contains 17 carbons atoms in one five-membered and three six-membered rings.
Steroids
89
It is a C27 steroid molecule that is a component of cell membranes and a precursor for other steroid-based lipids. It is the most abundant steroid in the human body.
Cholesterol
90
Two types of lipoproteins that carry cholesterol throughout the body:
- LDL (low-density lipoprotein), or bad” cholesterol,
- HDL (high-density lipoprotein), or “good” cholesterol,
91
It is known as the "good" cholesterol because it helps remove other forms of cholesterol from your bloodstream. Higher levels of it are associated with a lower risk of heart disease.
High-density lipoprotein (HDL) cholesterol
92
High levels of this cholesterol can eventually build up within the walls of your blood vessels and narrow the passageways. Sometimes a clot can form and get stuck in the narrowed space, causing a heart attack or stroke. This is why it is often referred to as "bad" cholesterol.
Low-density lipoprotein cholesterol.
93
It is a biochemical substance, produced by a ductless gland, that has a messenger function. Hormones serve as a means of communication between various tissues. Some of them, though not all, are lipids.
Hormone
94
There are two major classes of steroid hormones:
(1) sex hormones and (2) adrenocorticoid hormones
95
A type of steroid hormone, which control reproduction and secondary sex characteristics
sex hormones
96
A type of steroid hormone, which regulate numerous biochemical processes in the body.
adrenocorticoid hormones
97
The sex hormones can be classified into three major groups:
1. Estrogens—the female sex hormones
2. Androgens—the male sex hormones
3. Progestins—the pregnancy hormones
98
These are synthesized in the ovaries and adrenal cortex and are responsible for the development of female secondary sex characteristics at the onset of puberty and for regulation of the menstrual cycle. They also stimulate the development of the mammary glands during pregnancy and induce estrus (heat) in animals.
Estrogens
99
These are synthesized in the testes and adrenal cortex and promote the development of male secondary sex characteristics. They also promote muscle growth.
Androgens
100
These are synthesized in the ovaries and the placenta and prepare the lining of the uterus for implantation of the fertilized ovum. They also suppress ovulation.
Progestins
101
These are the primary estrogen; responsible for secondary female characteristics.
Estradiol
102
the primary androgen; responsible for secondary male characteristics
Testosterone
103
the primary progestin; prepares the uterus for pregnancy
Progesterone
104
it is a synthetic progestin
Norethynodrel
105
a synthetic tissue-building steroid
methandrostenolone
106
The second major group of steroid hormones consists of the __________________. Produced by the adrenal glands, small organs located on top of each kidney
adrenocorticoid hormones
107
There are two types of adrenocorticoid hormones.
- Mineralocorticoids
- Glucocorticoids
108
Types of adrenocorticoid hormones that control the balance of Na+ and K+ ions in cells and body fluids.
Mineralocorticoids
109
Types of adrenocorticoid hormones that control glucose metabolism and counteract inflammation.
Glucocorticoids
110
An __________ is an oxygenated C20 fatty acid derivative that functions as a messenger lipid. Almost all cells, except red blood cells, produce this.
eicosanoid
111
It is a messenger lipid that is a C20-fatty-acid derivative that contains a cyclopentane ring and oxygen-containing functional groups. It is named after the prostate gland, which was first thought to be their only source.
Prostaglandins
112
A _____________- is a messenger lipid that is a C20-fatty-acid derivative that contains three conjugated double bonds and hydroxy groups. Their source and the presence of the three conjugated double bonds account for their name.
leukotriene
113
A ______________ is a messenger lipid that is a C20-fatty-acid derivative that contains a cyclic ether ring and oxygen-containing functional groups. Its important function is to promote the
formation of blood clots. They are produced by blood platelets and promote platelet aggregation.
thromboxane
114
A ______________ is a lipid that is a monoester of a long-chain fatty acid and a long chain alcohol. They are monoesters, unlike fats and oil are triesters. The fatty acids found in them generally are saturated and contain from 14 to 36 carbon atoms. The alcohols found in them waxes may be saturated or unsaturated and may contain from 16 to 30 carbon atoms.
biological wax
115
_____________, secreted by the sebaceous glands of the skin, contains waxes that help to keep skin soft and prevent dehydration.
Sebum
