15.3 Waxes and Triacylglycerols

15.3 Waxes and Triacylglycerols

• The structures and functional groups of the two groups are compared.

• The formula for a wax or triacylglycerol can be drawn.

• Wax on the leaves and stems of plants helps prevent loss of water and damage from pests.
• A waterproof coating is provided by the fur, feathers, and skin of animals.

• honeycombs and carnauba wax from palm trees are used to give a protective coating to furniture, cars, and floors.
• Candles and cosmetics are made from Jojoba wax.
• Lanolin, a mixture of waxes obtained from wool, is used in hand and facial lotions to aid retention of water.

• Waxes are made from long-chain alcohols and fatty acids.

• The name stearic acid is given to glyceryl tristearate.
• The compound is called tristearin.

• Most naturally occurring triacylglycerols contain glycerol, which is usually found in two or three dif ferent fatty acids.
• A mixture of triacylglycerol might be made from stearic acid, oleic acid, and palmitic acid.

• The formula for glyceryl tripalmitoleate is called the Condensed Structural formula.

• Draw the structural formulas for the two acids.

• They use triacylglycerols to make creams and lotions.

• The triacylglycerol contains three molecules of myristic acid.

• The major form of energy storage for animals is triacylglycerols.
• Plants, seeds, and nuts are high in calories and are eaten by animals.
• The animal goes into sleep when the temperature drops.
• The body temperature plummets and cellular activity and heart rate plummets.
• Animals that live in extremely cold climates are able to sleep for up to 7 months.
• A polar bear is the only source of energy during this time.

• Olive oil and peanut oil have large amounts of oleic acid.

• The oils from corn, cottonseed, safflower seed, and sunflower seed contain large amounts of saturated and monounsaturated fat, which makes them a type of polyunsaturated oil.
• The saturated fat in animal fats is more than the saturated fat in vegetable oils.
• The melting points of animal fats are higher than those of vegetable oils.

• Palm oil and coconut oil contain a lot of saturated fat.
• Half of the saturated fat in coconut oil is lauric acid, which has 12 carbon atoms instead of 18 carbon atoms found in the stearic acid of animal sources.
• Coconut oil has a melting point that is higher than typical vegetable oils, but not as high as fats from animal sources that contain stearic acid.

• The Try Practice Problems 15.25 percentage of unsaturated fatty acids in vegetable oils is higher than in animal fats.