Lipids and Lipoproteins Flashcards
Lipids are soluble in ___.
Non-polar organic solvents.
Lipids are ___ elements of biomembranes and organelles.
structural.
Lipids are a source of biochemical fuel via ___.
Beta-oxidation.
How do lipids act as a precursor?
(1) Hormones and prostaglandins involved in homeostasis
(2) Bile acids in dietary fat absorption
(3) Fat soluble vitamins involved in regulatory and coenzyme function
What are the three essential fatty acids?
Linolenic acid, arachidonic acid, and linoleic acid.
How is a fatty acid determined to be saturated or unsaturated?
By the presence of one or more double bonds.
Which type of fatty acid is liquid at room temperature?
Unsaturated fatty acid.
What are the components of the structure of fatty acids?
(1) Carbon/hydrogen chain
(2) Carboxyl end
(3) Methyl end
(4) Omega-terminal methyl
Free fatty acids in the blood are transported by what protein?
Albumin.
Fatty acids are stored as ___ within ___ tissues.
triglycerides; adipose
How do we obtain amino acids?
Through diet or synthesized from AcetylCoA in the TCA cycle.
Describe the structure of triglycerides.
Glycerol with three fatty acid linkages.
Synthesis and degradation of triglycerides are controlled by what hormone?
Insulin.
Which lipoprotein transports triglycerides?
VLDL.
Which lipoprotein transports exogenous triglycerides (i.e. triglycerides we obtain from food)?
Chylomicrons.
Describe the structure of phospholipids.
Glycerol + Phosphoric Acid + Two Fatty Acids.
What is the primary function of phospholipids?
Used for cellular membranes, cell signaling, blood clotting activity, and lipid transport.
Sphingolipids are ___ of alcohol.
Esters.
What is the function of sphingomyelin?
(1) Cell membranes of RBC’s & nerve sheath.
(2) Plays a role in brain and nerve tissue transmission.
What is the function of prostaglandins?
Immunologic activity and inflammation function.
What is the function of thromboxane?
Platelet aggregation.
What is the function of leukotriene?
Inflammatory response.
What are examples of isoprenoids/terpenes?
(1) Vitamins A, E, and K precursors.
(2) Cholesterol and derivatives precursor.
Cholesterol is a ___; complex alcohol.
sterol
Endogenous cholesterol is synthesized in the liver from ___.
acetyl CoA.
What is the enzyme used for endogenous cholesterol synthesis?
HMG-CoA reductase.
Which enzyme is used for cholesterol esterification in HDL in plasma?
Lecithin cholesterol acyltransferase (LCAT).
Which enzyme is used for cholesterol esterification in HDL in tissue?
Acyl-cholesterol acyltransferase (ACAT).
When fatty acids have been exhausted in the body, what is an alternative form of energy?
Ketone Bodies.
What are the three major ketone bodies used when in starvation?
(1) B-hydroxybutyrate; (2) acetoacetate; (3) acetone.
