Chapter 6

very low density lipoprotein (VLDL)

cholesterol and triglycerides covered with a shell of protein and lipids, activates LDL to transfer triglycerides from this type of lipoprotein to body cells like adipose tissue for fat storage or muscle tissue for energy.

lecithins

family of phospholipids synthesized by the body and found in foods such as peanuts, wheat germ, soy, egg yolks, and liver. High doses can cause gas, diarrhea, and weight gain.

essential fatty acids (EFA)

fats that humans must get from foods because our bodies are unable to synthesize these types of fatty acids. (ex: linoleic and alpha-linoleic fatty acids)

free fatty acids

fatty acids released from the glycerol backbone (aren't connected to any molecule). Have a variety of structures, but all are similar.

monounsaturated fatty acid (MUFA)

fatty acids with one double bond in the carbon chain (one location isn't saturated with hydrogen) Looks bent.

cholestokinin (CCK)

hormone triggered by the presence of fat in the small intestine that stimulated the release of bile from the galbladder and lipase and colipase from the pancreas, which are then delivered to the small intestine through the common bile duct (bile is used to emulsify fats).

Eicosanoids

hormone-like compounds produced from multiple types of linoleic acid that affect the body in the region where they are produced (aka local hormones) and have hundreds of functions in the human body.

prostaglandins

potent type of eicosanoid compounds that produce diverse effects in the body.

de-esterification

process of releasing fatty acids from a glycerol

re-esterification

re-attaching a fatty acid to a glycerol that has lost one.

triglyceride

the chief form of fat in food, a molecule consisting of three fatty acids (which can vary in type) attached to a glycerol serving as a backbone for the fatty acids.

micelles

water-soluble spherical structure of fat molecules formed by lecithin and bile acids. Hydrophobic parts face inwards, hydrophilic parts face outwards.

antioxidant

a compound that protects other compounds from oxygen's damaging effects, like reducing LDL oxidization which lowers the risk of cardiovascular disease.

polyunsaturated fatty acid (PUFA)

a fatty acid with at least 2 double bonds in a carbon chain (at least two locations not filled with hydrogen) Looks extremely bent.

monoglyceride

a glycerol molecule with one fatty acid attached

hydrogenation

adding hydrogen to the carbon chain of unsaturated fatty acids, converting liquid fats into solids. (the more hydrogen added, the more saturated the fatty acid becomes)

saturated fatty acid (SFA)

all bonds between the carbons in a fat molecule are single connections and other carbon bonds are filled with hydrogen. (no bonds are empty) Looks straight.

atherosclerosis

also known as hardening of the arteries, happens when buildup of fatty material (plaque) in the arteries occurs. Can choke off blood supply to organs, which can lead to heart attack and other problems.

mediterranean diet

A dietary pattern associated with cultures bordering the Mediterranean Sea; the pattern emphasizes whole grains, fruits, vegetables, legumes, nuts, seeds, fish, and olive oil and limits meat, saturated fat, and full-fat dairy products.

emulsifier

compound that can suspend fat in water by isolating individual fat droplets using a shell of water molecules or other substances to prevent the fat from coalescing. Essential for fat's digestion and transportation through the blood stream.

lipoproteins

compounds containing a core of lipids with a shell composed of protein, phospholipids, and cholesterol (the shell allows the __________ to circulate in blood).

low-density lipoproteins (LDL)

created as IDL's lose more and more triglycerides, composed mostly of cholesterol. Removed from blood by cells with the _______ receptor B-100 (found in the liver and some other cells). Once inside a cell, this lipoprotein is broken down in to protein and free cholesterol, used to maintain the cell membrane pr synthesize special compounds like estrogen, testosterone, or Vit. D.

delta system

describes fatty acids in relation to the tail end of the carbon chain.

trans fatty acids

hydrogens attached to double bonded carbons, zigzag back and forth across the carbon chain. Created through a process called hydrogenation, found often in prepackaged and fried foods.

omega system

indicates where the first double bond occurs closest to the methyl (head) of the chain.

chylomicrons

lipoprotein made of dietary fats surrounded by a shell of cholesterol, phospholipids, and protein. Carries fat from the small intestine to cells, identified by letters A-E and subclasses. Can trigger certain enzymes and assist in building lipoproteins on cell surfaces.

diglyceride

molecule with two fatty acids attached to a glycerol

High-density lipoprotein (HDL)

the most dense lipoprotein because of its high proportion of protein, mostly produced in the liver and intestine. Roams the bloodstream, picking up cholesterol from dying cells or other sources, then gives it to other lipoproteins for transfer back to the liver, blocking the oxidization of LDL.

esterification

the process of attaching fatty acids to a glycerol molecule

phospholipid

type of fat similar to a triglyceride, except one fatty acid is replaced with a compound that contains mineral phosphorus, often with nitrogen attached. Can be synthesized by the body or found in the diet. Important because they can function in a watery environment without clumping together. Head is hydrophilic, tail is hydrophobic.

Intermediate Density Lipoprotein (IDL)

type of lipoprotein created when VLDL's get more and more dense. Activates the enzyme hepatic triglyceride lipase (HTGL) that take triglycerides from this type of lipoprotein, causing proportions of triglycerides to lower and cholesterol to rise.

sterols

type of steroid found in lipid form, instead of forming in to carbon chains, they are mostly arranged in rings. (cholesterol is most well-known form)