Understanding Triglycerides and Fatty Acids

Triglyceride (TAG)

Three fatty acids esterified to a glycerol backbone

Lipid Type Determination

Degree of unsaturation (more double bonds = oil)

Saturated Fatty Acid

A fatty acid with no double bonds

Monounsaturated Fatty Acid

A fatty acid with one double bond

Polyunsaturated Fatty Acid

A fatty acid with more than one double bond

Effect of Double Bonds on Melting Point

More double bonds = lower melting point

Cis vs Trans Fatty Acids

Cis have kinks; trans are straighter and less healthy

Fatty Acid Naming Systems

Common name, systematic name, omega (n or ω) system

what are essential Fatty Acids

Humans can't synthesize them due to enzyme limitations

Enzymes Modifying Fatty Acids

Elongases (add 2C) and desaturases (add double bonds)

Roles of Fatty Acids in the Body

Energy, membrane structure, signaling molecules

what enzymes allow triglyceride Digestion

pancreatic lipases into fatty acids and MAG

Chylomicrons

Lipoproteins that transport triglycerides from the gut to tissues

Enzyme Cleaving Fatty Acids off Chylomicrons

Lipoprotein lipase

what happens to chylomicron Remnants

They are cleared by the liver

Triglyceride Synthesis Requirement in Adipose Tissue

Glycerol-3-phosphate and activated fatty acids

Source of Glycerol-3-Phosphate

DHAP from glycolysis

Enzymes in TG Synthesis in Adipose Tissue

1-acylG-3-P acyltransferase and DGAT

Final Product of Lipogenesis

Triglyceride stored in fat droplets

Uses of Essential Fatty Acids

Membrane composition and signaling molecules