BIO 1050 Ch 5 Lipids

In the listing of ingreidents on a food label, the presence of _________ (2) is an indiciation that a product is a source of trans fats

- Margarine - Partially-hydrogenated oil

What are some examples of foods that are cholesterol-free?

- Margarine - Vegetable oil - Peanut butter - Vegetable shortening

What are the functions of HDL cholesterol in the bloodstream?

- Picks up cholesterol from dying cells and other sources - Donates cholesterol to other lipoprotein for transport back to the liver for excretion

The type of fat most likely not to become rancid are ________ and __________ because they contain fewer carbon-carbon double bonds

- Saturated fats - Trans fats

Which three organs and/or glands produce lipase?

- Stomach - Salivary glands - Pancreas

What happens to a food product when it becomes hydrogenated?

- Trans fatty acid content is increased - The molecular shape of the fats in the food resembles saturated fats

What are some food sources of EPA and DHA?

- Tuna - Salmon - Sardines

What two chemical groups are found at the end of either side of the fatty-acid carbon chain?

- Acid group (COOH) - Methyl group (CH3)

Fat digestion is rapid and thorough in the small intestine under what "right" circumstances?

- Bile is released from the gallbladder - Lipase breaks triglycerides down to monoglycerides

What are the functions of phospholipids in the body?

- Digestion of fats - Formation of cell membranes - Absorption and transport of nutrients

Why are triglycerides ideal for fat storage?

- Energy dense - Chemically stable

What are the major functions of fatty acids and trigylycerides in the body?

- Energy storage - Insulation - Transport of fat-soluble vitamins

What are the by-products from chylomicron digestion?

- Free fatty acids - Glycerol - Chylomicron remnant

What are functions of cholesterol?

- Helps form hormones - Provide structure to cells - Building block for bile acids

Which two fatty acids are considered essential?

- Linoleic - Alpha-linolenic

As components of cell membranes, phospholipids.....

Are a source of essential fatty acids for the cell

A long-chain fatty acid is defined as a fatty acid that contains _____ or more carbon atoms in length

12

The acceptable range for lipids is _____% to ______% of kilocalories

20, 35

According to AHA, to reduce the risk for cardiovascular disease, saturated fats should contribute no more than _____ to _____ of total kilocalories

5% to 6%

How do you convert a liquid oil to a solid fat at room temperature?

Add hydrogens to the liquid fat (hydrogenation)

Lipoprotein lipase breaks down triglycerides in the ____________

Bloodstream

Why are the chemical structures of trans and saturated fatty acids similar?

Both have a straight shape

What is a common example of sterols?

Cholesterol

What is the primary component of the lipoprotein LDL?

Cholesterol

_____________ is a type of lipid that is found only in foods of animal origin

Cholesterol

Which fatty acid has the following chemical structure: hydrogens are found on the same side of the carbon-carbon double bond?

Cis

Food manufacturers use the process of hydrogenation to.....

Convert liquid oils into more solid fats

The AHA recommends using plant oils rather than animal fats in food preparation to...

Decrease saturated fat intake

What is the health effect associated with consumption of polyunsaturated fatty acids?

Decreases blood levels of cholesterol

Pressure in the arterial blood vessels when the heart is between beats

Diastolic blood pressure

Essential fatty acids must be obtained from the _____

Diet

What are some examples of foods that contain cholesterol?

Eggs, ice cream, chicken

A major function of phospholipids (e.g. lecithin) in foods is to act as a(n) ______________

Emulsifier

_________ fatty acids must be supplied by the diet, whereas ________ fatty acids can be synthesized by the body and do not need to be supplied by the diet

Essential; nonessential

T/F: Most Americans need to drastically reduce the amount of fat they consume each day

False

Fat gives food products.....

Flavor, creaminess

Risk for development of cardiovascular disease increases when _______ levels are low and ______ levels are high in the bloodstream

HDL, LDL

What is the most important functions of the phospholipid molecule?

Help form cell membranes

A teaspoon of stick margarine has ________ trans fatty acids than a teaspoon of tub margarine

More

Which fatty acid has the following chemical structure: hydrogens are found on opposite sides of the carbon-carbon double bond?

Trans

What is the health effect associated with consumption of saturated fatty acids?

Increases blood levels of cholesterol

What the final destination of glycerol in the body?

It circulates back to the liver

What is the chemical structure of an omega-6 fatty acid?

It contains the first carbon-carbon double bond on the sixth carbon from the methyl end of the carbon chain

What is the chemical structure of an omega-3 fatty acid?

It contains the first carbon-carbon double bond on the third carbon from the omega end of the carbon chain

What the final destination of chylomicron remnant in the body?

It is removed from circulation by the liver and recycled to make other lipoproteins and bile acids

________ is a phospholipid and a major component of cell membranes

Lecithin

Which enzyme plays an important role in fat digestion?

Lipase

Chylomicrons, VLDL, LDL, and HDL are classified as ______________

Lipoproteins

___________ transport lipids from the small intestine and liver to body tissues

Lipoproteins

Monounsaturated and polyunsaturated fatty acids are typically __________ at room temperature

Liquid

Oils rich in unsaturated fatty acids are typically __________ at room temperature.

Liquid

The majority of fatty acids in the body and in foods are _______-chain fatty acids

Long

What are some examples of foods that are considered high in fat?

Margarine, butter, salad oils, mayo

Sterols contain a __________ structure

Multi-ring

What is the main function of antioxidants?

Neutralize free radicals

Essential fatty acid; alpha-linolenic acid

Omega-3

Reduced triglycerides, reduced blood clotting, and reduced pain from rheumatoid arthritis are benefits associated with intake of which fatty acids?

Omega-3

Which fatty acid decreases blood clotting and inflammation?

Omega-3

Fatty fish provide eicosapentaenoic acid (EPA) and docsahexaenoic acid (DHA), which are two _______________ that are important for brain and heart health

Omega-3 fatty acids

Essential fatty acid; linoleic acid

Omega-6

Which fatty acid increases blood clotting and inflammation?

Omega-6

Nonessential fatty acid

Omega-9

Monounsaturated fatty acids have what type of carbon bond?

One double bond

The majority of fat digestion is accomplished by ________ __________

Pancreatic lipase

Liquid fat at room temperature is a _________________________ fat

Polyunsaturated

What is the primary component of the lipoprotein HDL?

Protein

____________ occurs when the double bonds in unsaturated fatty acids in food products are broken down by ultraviolet light or oxygen

Rancidity

Why is the potential for fat rancidity a problem for manufacturers?

Rancidity of fats decreases the food's shelf life

Animal fats are high in ___________ fatty acids

Saturated

Egg yolks are rich in ______________ fatty acids, but not trans fatty acids

Saturated

Which two fatty acids tend to increase LDL-cholesterol in the blood?

Saturated, trans

Saturated fatty acids have what type of carbon bond?

Single

The more saturated a fat is, the more ____________ it is at room temperature

Solid

What is the function of an emulsifier?

Suspends fats in water

Pressure in the arterial blood vessels associated with pumping of the blood from the heart

Systolic blood pressure

_________ fatty acids tend to decrease HDL-cholesterol in the blood

Trans

Compared to foods made with unprocessed plant oils, partially hydrogenated oils are less likely to go rancid because....

They have fewer double bonds

How are long-chain fatty acids absorbed?

They reform into a triglyceride in the intestinal absorptive cell and travel through the lymphatic system

How are short and medium-chain fatty acids absorbed?

They travel as a water-soluble molecule through the portal vein to the liver

The first five ingredients listed on the label for cake frosting are sugar, vegateble oil, shortening (made with partially hydrogenated soybean and cottonseed oils), water and corn syrup. This product is a rich source of ____________

Trans fatty acids

High levels of HDL in the blood tend to slow the development of cardiovascular disease because HDL......

Transports cholesterol from the bloodstream to the liver for excretion

Three fatty acids combine with glycerol to form a __________________

Triglyceride

What is the primary component of the lipoprotein Chylomicron?

Triglyceride

What is the body's most efficient form of stored energy?

Triglycerides

T/F: The hydrogenation process produces trans fats

True

T/F: The process of oxidation usually changes the shape and/or function of a substance

True

Polyunsaturated fatty acids have what type of carbon bond?

Two or more double bonds

Is an omega-3 fatty acid saturated or unsaturated?

Unsaturated

Margarine is made from plant oils which are rich in ______________ fatty acids

Unsaturated

Omega-6 fatty acids are also called ____________ fatty acids

Unsaturated

Why do reduced-fat foods contain the same, or similar, amount of calories as their reference foods?

When fat is removed, sugar is usually added to maintain a palatable flavor and texture, usually resulting in similar energy density

Can cholesterol be made by the body?

Yes

Can sterols be produced by the body?

Yes