Lipids Flashcards
__________ known as fats provide a major way of storing chemical energy and carbon atoms in the body.
Lipids
They surround and insulate vital body organs, providing protection from mechanical shock and preventing excessive loss of heat energy.
Fats
These are the basic
components of cell membranes.
Phospholipids, glycolipids, and cholesterol
Several cholesterol derivatives function as chemical messengers (_____________) within the body.
hormones
A __________ is an organic compound found in living organisms that is insoluble (or only sparingly soluble) in water but soluble in nonpolar organic solvents.
lipid
Lipids are _________ molecule, their structure are relatively large and non-polar.
hydrophobic
Lipids are ____________, which means they contain both nonpolar and polar regions
amphipathic
Two classifications of lipids
- Saponifiable
- Nonsaponifiable
These lipids are composed of long-chain fatty acids that form esters.
Saponifiable lipids
These lipids are composed of ring structures that do not form esters.
Nonsaponifiable lipids
(Classifications of lipids) Ester linkages are present in _________, while it is absent in ___________.
saponifiable, nonsaponifiable
The structure of these lipids are long chain fatty acids connected to a functional group of alcohol through an ester linkage.
Saponifiable lipids
Two types of non-saponifiable lipids are __________ and ___________
- terpenes
- steroids
____________ are made of isoprene units, and ___________ are made of 17 carbon atoms arranged in rings
Terpenes, steroids
These lipids function as structural components.
Saponifiable
These lipids act as biochemical compounds, storage, and structural component.
Non-saponifiable lipids
Two categories of lipids
Simple lipids and Complex lipids
Two simple lipids:
(a) Fats and oils (triacylglycerols)
(b) Waxes
Complex (or compound) lipids:
(a) Phospholipids:
(b) Glycolipids
(c) Lipoproteins
(d) Other complex lipids
Types of phospholipids
- Glycerophospholipids
- Sphingophospholipids
Based on biochemical function, lipids are divided into five categories:
- Energy-storage lipids
- Membrane lipids
- Emulsification lipids
- Messenger lipids
- Protective-coating lipids
(Biochemical functions) These are energy-storage lipids
triacylglycerols
(Biochemical functions) These are membrane lipids
phospholipids, sphingoglycolipids,
and cholesterol)
(Biochemical functions) These are emulsification lipids
bile acids
(Biochemical functions) These are messenger lipids
steroid hormones and eicosanoids
(Biochemical functions) These are protective-coating lipids
biological waxes
It is a naturally occurring monocarboxylic acid.
fatty acid
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).
They are rarely found free in nature but rather occur as part of the structure of more complex lipid molecules.
Fatty acids
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).
It is a fatty acid with a carbon chain in which all carbon–carbon bonds are single bonds.
saturated fatty acid
It is a fatty acid with a carbon chain in which one carbon–carbon double bond is present.
monounsaturated fatty acid
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
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
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 (⧊)
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)
It is an unsaturated fatty acid with its endmost double bond three carbon atoms away from its methyl end.
omega-3 fatty acid
It is an unsaturated fatty acid with its endmost double bond six carbon atoms away from its methyl end.
omega-6 fatty acid
Saturated fatty acids with structural notation of 12:0
lauric acid
Saturated fatty acids with structural notation of 14:0
myristic acid
Saturated fatty acids with structural notation of 16:0
palmitic acid
Saturated fatty acids with structural notation of 18:0
stearic acid
Saturated fatty acids with structural notation of 20:0
arachidic acid
Monosaturated fatty acid with structural notation 16:1(⧊ 9) w-7
palmitoleic acid
Monosaturated fatty acid with structural notation 18:1(⧊ 9) w-9
oleic acid
Polyunsaturated fatty acid with structural notation 18:2(⧊ 9,12) w-6
linoleic acid