BioChem Lipids Flashcards
a heterogeneous class of naturally occurring organic compounds classified together on the basis of common solubility properties
Lipids
an ester of glycerol with three fatty acids.
Triglyceride
Triglycerides rich in unsaturated fatty acids are generally liquid at room temperature and are called?
oils
Triglycerides rich in saturated fatty acids are generally semisolids or solids at room temperature and are called?
fats
reduction of some or all of the carbon-carbon double bonds of an unsaturated triglyceride using H2/transition metal catalyst
Hardening
contain an alcohol, two fatty acids, and a phosphate ester
Phospholipids
In glycerophospholipids, the alcohol is ?
glycerol
In glycerophospholipids, the _____ is glycerol
alcohol
In sphingolipids, the alcohol is?
sphingosine
Complex lipids that contain a carbohydrate
Glycolipids
are the second most abundant group of naturally occurring lipids
Glycerophospholipids
They are also called phosphoglycerides
Glycerophospholipids
Found in the coatings of nerve axons (myelin)
Sphingolipids
Contain the long-chain aminoalcohol, sphingosine, from which this class of compounds in named
Sphingolipids
a complex lipid that contains a carbohydrate
Glycolipid
a group of plant and animal lipids that have this tetracyclic ring structure
Steroids
is the most abundant steroid in the human body, and also the most important
Cholesterol
It is a component in plasma membranes in all animal cells
Cholesterol
It is the precursor of all steroid hormones and bile acids
Cholesterol
Cholesterol, along with fats, are transported by ?
lipoproteins
Transport of cholesterol from the liver starts with ?
VLDL
male sex hormones
Androgens
responsible for the development of male secondary sex characteristics
Androgens
synthesized in the testes
Androgens
female sex hormones
Estrogens
synthesized in the ovaries from progesterone
Estrogens
responsible for the development of female secondary sex characteristics and control of the menstrual cycle
Estrogens
synthesized in the adrenal cortex.; regulate metabolism of carbohydrates
Glucorticoid hormones
the oxidation products of cholesterol
Bile Salts
synthesized in the liver, stored in the gallbladder, and secreted into the intestine
Bile Salts
a family of compounds that have the 20-carbon skeleton of prostanoic acid
Prostaglandins
catalyzes the normal physiological production of prostaglandins
COX-1
is responsible for the production of prostaglandins in inflammation
COX-2
are also derived from arachidonic acid
Thromboxanes
induces platelet aggregation and vasoconstriction
Thromboxane A2
are also synthesized from arachidonic acid
Leukotrienes
they are 100 times more potent than histamine
Leukotrienes
They occur mainly in leukocytes
Leukotrienes
Most of the cholesterol is carried by ?
LDL
Normal plasma levels are ?
175 mg/100 mL
in this disease, there are not enough LDL receptors and plasma levels of cholesterol may be as high as 680 mg/100 mL
hypercholesterolemia
These high levels of cholesterol can cause ?
premature atherosclerosis and heart attacks
insoluble in water, but soluble in organic solvents
Lipid
form the membranes around cells and small structures within cells
Complex lipids
In aqueous solution, complex lipids spontaneously form into a ?
lipid bilayer
these are in contact with the aqueous environment in the lipid bilayer
Polar (hydrophilic) head groups
these are buried within the bilayer and shielded from the aqueous environment.
Nonpolar (hydrophobic) tails
The major force driving the formation of lipid bilayers
hydrophobic interaction
Glycerophospholipids are found almost exclusively in plant and animal membranes, which typically consist of ________ phosphoacylglycerols and ________ proteins
40% -50% phosphoacylglycerols
50% - 60% proteins
a molecule in which glycerol is esterified with two molecules of fatty acid and one of phosphoric acid
phosphatidic acid
three most abundant fatty acids in phosphatidic acids
P S O
Palmatic, Stearic, and Oleic
The fatty acid on carbon 2 of glycerol is always ?
unsaturated
number of LDL receptors is controlled by a ?
feedback mechanism
When the concentration of cholesterol inside cells is high, the synthesis of LDL receptors is ?
suppressed
high LDL means ?
high cholesterol content in the plasma
high LDL together with low HDL is a symptom of ?
faulty cholesterol transport
controls cholesterol synthesis in the liver
serum cholesterol level
regulate metabolism of carbohydrates
Glucorticoid hormones
when serum cholesterol is high, its synthesis in the liver is ?
low
decrease inflammation
Glucorticoid hormones
involved in the reaction to stress
Glucorticoid hormones
