Nutrition Basics: Chapter 5 Lipids

Vocabulary based flashcards covering the definitions of lipid types, chemical structures, digestive processes, and health-related markers as presented in Chapter 5.

Lipids

A family of organic compounds that are mostly insoluble in water, yield high energy, and are composed mainly of carbon, hydrogen, and oxygen.

Triacylglycerols

Also known as triglycerides, these are the most common class of lipids and consist of three molecules of fatty acids and one molecule of glycerol.

Phospholipids

A type of lipid found in plants and animals (making up approximately $2\%$ of lipids) that features a glycerol backbone, two fatty acid molecules, and a phosphate group coupled with a nitrogen-containing group.

Sterols

Complex lipid molecules, such as cholesterol, that contain interlinking rings of carbon atoms with side chains of carbon, hydrogen, and oxygen.

Adipose tissue

Fatty tissue in the body consisting of masses of fat-storing cells where excess energy from food is digested and incorporated.

Cholesterol

An important component of the cell membrane required for the synthesis of sex hormones, vitamin D, and bile salts.

Cardiovascular disease

A disease of the heart or blood vessels.

Bioavailability

The proportion of a nutrient that is absorbed and utilized by the body; related to the generally accepted range for body fat ($10\%$ to $20\%$ for males and $20\%$ to $32\%$ for females).

Phytochemicals

Nonessential plant compounds considered to have a beneficial impact on human health.

Satiety

The sensation of fullness often contributed to by fats in food.

Fatty acids

An organic compound containing a carboxylic acid group ($−COOH$) at one end and a methyl group ($−CH_3$) at the other.

Saturated fatty acid

A fatty acid containing the maximum number of hydrogen atoms with no points of unsaturation.

Unsaturated fatty acid

A fatty acid that is missing hydrogen atoms and contains one or more points of unsaturation (carbon-carbon double bonds).

Polyunsaturated fatty acid

A fatty acid containing two or more points of unsaturation.

Essential fatty acids

Fatty acids that the body cannot synthesize and must be supplied through the diet, specifically Omega-3 and Omega-6.

Eicosanoids

Compounds derived from polyunsaturated fatty acids that control several body functions.

Docosahexaenoic acid (DHA)

An omega-3 fatty acid that is especially important for brain growth and development in infants.

Amphiphilic

A compound that possesses both water-loving (hydrophilic) and fat-loving (hydrophobic) properties.

Emulsifiers

Compounds that allow two immiscible liquids, such as oil and water, to combine so that no separation occurs.

Lipase

An enzyme responsible for the breakdown of triacylglycerols and phospholipids.

Bile

A substance secreted by the liver containing bile salts, lecithin, and cholesterol derivatives that aids in the absorption and digestion of fats.

Monoglycerides

A product of lipid digestion consisting of a glycerol molecule with one fatty acid attached.

Micelles

An aggregate of phospholipids and other fats and fat-soluble vitamins that cross through the brush border into the enterocytes.

Lipoprotein

A protein-lipid complex used to transport fat through the watery environments of the blood and lymph.

Chylomicron

A large lipoprotein structure formed in the intestinal lining that transports fats through the lymph system.

VLDLs (Very low-density lipoproteins)

Lipoproteins made in the liver from chylomicron remnants that transport triacylglycerols and other lipids to various body tissues.

LDLs (Low-density lipoproteins)

Commonly known as "bad cholesterol," these carry cholesterol into cells but can deposit it into blood vessel walls.

HDLs (High-density lipoproteins)

Known as "good cholesterol," these scavenge excess cholesterol and deliver it back to the liver for reuse or disposal.

Oxidation

The loss of at least one electron when two or more substances interact; oxidized LDL can speed up plaque formation in arteries.

Linolenic acid

An omega-3 fatty acid that is essential for human health.

Linoleic acid

An omega-6 fatty acid that is essential for human health.

Arachidonic acid (ARA)

An omega-6 fatty acid that serves as a precursor to the synthesis of eicosanoids.