CLASSIFICATIONS, ENERGY-STORAGE LIPIDS: TRIACYLGLYCEROLS (+ Fats and Oils) Flashcards
Two common methods exist for sub-classifying lipids into families for the purpose of study.
a. biochemical function of a lipid as the basis for classification
b. based on whether or not a
lipid can be broken down into smaller units through basic hydrolysis
A hydrolysis reaction that occurs in basic solution is called a _________.
saponification reaction
BASED ON BIOCHEMICAL FUNCTION, LIPIDS ARE DIVIDED INTO FIVE CATEGORIES
● Energy-storage lipids (triacylglycerols)
● Membrane lipids (phospholipids,
sphingoglycolipids, and cholesterol)
● Emulsification lipids (bile acids)
● Messenger lipids (steroid hormones and
eicosanoids)
● Protective-coating lipids (biological
waxes)
BASED UPON WHETHER OR NOT SAPONIFICATION
OCCURS WHEN A LIPID IS PLACED IN BASIC AQUEOUS SOLUTION, LIPIDS ARE DIVIDED INTO TWO
CATEGORIES:
a. Hydrolyzable/Saponifiable lipids
b. Nonhydrolyzable lipids
The most widespread energy-storage material within cells is the
carbohydrate glycogen
Lipids known as __________ also function within the body as energy-storage materials.
triacylglycerols
Rather than being widespread, triacylglycerols
are concentrated primarily in special cells (___________) that are nearly filled with the
material.
adipocytes
Adipose tissue containing these cells is found in various parts of the body:
under the skin, in the abdominal cavity, in the mammary glands, and around various organs.
Triacylglycerols are __________; three ester functional groups are present.
triesters
_________ are the carboxylic acids involved in
triacylglycerol formation.
Fatty acids
_____ are naturally occurring mixtures of triacylglycerol molecules in which many
different kinds of triacylglycerol molecules are
present.
fats and oils
A ____ is a triacylglycerol mixture that is a solid or a semisolid at room temperature (25 °C). Generally, these are obtained from animal sources.
fat
An ____ is a triacylglycerol mixture that is a liquid at room temperature (25 °C). Generally, these are obtained from plant sources.
oil
Fats are composed largely of triacylglycerols in which __________ fatty acids predominate.
saturated
Oils contain triacylglycerols with larger amounts of
____________________ fatty acids than those in fats.
mono- and polyunsaturated