BIOCHEM part 3: Waxes and Triacylglycerols

Waxes are esters formed from ________ and __________

a fatty acid and a high molecular weight alcohol

Because of their long nonpolar C chains, waxes are very (hydrophilic or hydrophobic)?

hydrophobic

Waxes form ________________ on bird’s feathers and sheep’s wool and make up beeswax.

protective coatings

Waxes are hydrolyzed with __________ the presence of acid or base

water

what are the products of the hydrolysis of waxes?

carboxylic acid and alcohol

Triacylglycerols (triglycerides) are three esters formed from _______and __________________

glycerol and three molecules of fatty acids

________________ triacylglycerols have three identical fatty acid side chains.

Simple triacylglycerols

______________ triacylglycerols have two or three different fatty acids.

Mixed triacylglycerols

_______________ triacylglycerols contain only saturated fatty acids

Saturated triacylglycerols

Saturated triacylglycerols make up ______________ and are _______ at room temperature

most animal fat, solid

_______________ triacylglycerols contain at least one unsaturated fatty acid.

Unsaturated triacylglycerols

Unsaturated triacylglycerols make up ______________ and are _______ at room temperature

most vegetable oils, liquids

(Monounsaturated/Polyunsaturated) triacylglycerols have 1 C=C bond.

Monounsaturated triacylglycerols

(Monounsaturated/Polyunsaturated) triacylglycerols have many C=C bonds.

Polyunsaturated triacylglycerols

Increasing the number of double bonds in the fatty acid chain (INCREASES/DECREASES) the melting point of the triacylglycerol.

decreases

are derived from fatty acids with a few double bonds; have higher melting points

Fats

Fats are (solids/liquids) at room temperature

solids

are derived from fatty acids that have a large number of double bonds; they have lower melting points;

Oils

Oils are (solid/liquid) at room temperature

liquids

are formed when triacylglycerols are partially hydrogenated

Trans double bonds

the healthiest oil to use for cooking are:

canola and olive oil

Fats are used to build __________, _______ the body, store ___________ for later use

build cell membranes

insulate the body

store energy

it is recommened that no more than __________% of caloric intake shoud come from lipids

20 to 35%

a high intake of saturated TAG is linked to ___________

heart disease

Saturated fats stimulate ________ synthesis, which can lead to __________________ building up inside arteries

cholesterol synthesis

cholesterol plaques

Cholesterol plaque build up can result in _______________

high blood pressure

heart attack

stroke

Give foods rich in saturated TAG

fatty red meat

cheese

butter

fried foods

ice cream

Foods w/ saturated TAG (increase/decrease) blood cholesterol level

increase

Give foods rich in unsaturated TAG

plant oils

nuts

soybeans

fish

Foods rich in unsaturated TAG (increase/decrease) blood cholesterol levels

decrease

Give foods rich in trans TAG

margarine

processed food

fried foods

some baked goods

__________________ TAG lower the risk of heart diseae by decreasing the level of cholesterol in the blood

Unsaturated TAG

TAG formed from omega ________ fatty acids are very helping in lowering the risk of heart attack

omega-3 fatty acids

_______ act like saturated fats and increase the cholesterol levels in the blood

Trans fats

Trans fats are ______________ instead of naturally occuring

primarily synthesized

Humans store energy as triacylglycerols ____________ cells below the surface of the skin, in the breast area, and surrounding internal organs.

adipose cells

The number of adipose cells is (dynamic/constant); weight gained or lost causes them to swell or shrink, but not decrease or increase in number.

constant

To metabolize triacylglycerols for energy, the esters are hydrolyzed by enzymes called ___________

lipases

Complete metabolism of a triacylglycerol yields _______, ________ and a great deal of _______

CO2, H2O, and a great deal of energy

The average content of men and women is ~_____% and ~___% respectively. This stored fat provides ________ months of the body’s energy needs.

~20% and ~25%

two to three months