HUN 1201 CH 5 Test It

4) Describe the structure of a triglyceride.

composed of a molecule of glycerol with three fatty acids attatched

1c) What features do fats bring to foods?

protects against oxidation and alters the texture of foods

15a) How does excessive fat intake influence health?

provides energy without nutrients and leads to obesity, heart disease, and/or cancer

5a) What does hydrogenation do to fats?

reduces the number of hydrogen bonds in monounsaturated and polyunsaturated fatty acids to make them more saturated and more resistant to oxidation

3b) Describe the roles of the omega fatty acids in disease prevention.

support a healthy immune system and suppress inflammation

8) The difference between CIS - and TRANS- fatty acids is:

the configuration around the bond CIS - on the same side of the bond TRANS - opposite sides of the bond

2) What features distinguish fatty acids from each other?

the length of their carbon chains, the degree of unsaturation which is associated with the the number and location of their double bonds

3a) What does the term OMEGA mean with respect to fatty acids?

used by chemists to refer to the position of the closest double bond to the methyl(CH3) end of a fatty acid carbon chain

18) What is the Daily Value for fat (for a 2000-kcalorie diet)?

20-35% which is 400-700 kcalories (45-75 grams)

19) A person consuming 2,200 kcalories a day who wants to meet health recommendations should limit daily fat intake to:

50-85 grams

Highlight 5

High-Fat Foods - Friend of Foe? (pp. 164-169)

5b) What are trans-fatty acids, and how do they influence heart disease?

hydrogenated fatty acids whose hydrogen double bonds occur on opposite sides of the bond; these fatty acids now behave more like saturated fats by increasing blood cholesterol which increases the risk of heart disease

14) The essential fatty acids include:

linoleic (18 carbons/Omega-6) and linolenic acids (18 carbons/Omega-3)

12) Transport vehicles for lipids are called:

lipoproteins

16b) List ways to reduce fat and cholesterol intake.

replace saturated, trans-fats, and cholesterol with foods rich in monounsaturated and polyunsaturated fats - such as seafood, nuts, seeds, and vegetable oils

11) Chylomicrons are produced in the:

small intestine

10a) What do lipoproteins do?

they transport fat through the watery bloodstream to the rest of the body for immediate use or storage

7) A triglyceride consists of:

three fatty acids attached to a glycerol

20) List foods that are high in saturated fats and foods that are high in unsaturated fats that could easily be use to replace them.

use olive oil instead of butter salmon for steak mixed nuts for potato chips

15b) What factors influence LDL, HDL, and total blood cholesterol?

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LEARN IT - Highlight 5 Identify which fats support health and which impair it.

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10b) What are the differences among the chylomicrons, VLDL, LDL, and HDL?

CHYLOMICRONS (lipoprotein) - the greatest and densest is designed to transport DIET-DERIVED lipids (triglycerides) from the small intestine (via the lymph system) to the rest of the body (largest and contain mostly dietary triglycerides) VLDL (Very-Low Density Lipoproteins) - made primarily by LIVER cells to transport lipids to various tissues in the body (smaller and are about half triglycerides) LDL (Low-Density Lipoproteins) - derived from VLDL and become LDL as triglycerides are removed and broken down; composed primarily of cholesterol (all smaller than VLDL but contain mostly cholesterol) HDL (High-Density Lipoproteins) - the type of lipoprotein that transports cholesterol back to the liver from the cells for recycling or disposal; composed primarily of proteins (the densest and are rich in protein)

17) The lipoprotein most associated with a high risk of heart disease is:

LDL

5.4

Lipids in the Body (pp. 148-150)

LEARN IT - 5.2 Describe the chemistry, food sources, and roles of phospholipids and sterols.

Phospholipids, including lecithin, have a unique chemical structure that allows them to be soluble in both water and fat. The food industry uses phospholipids as emulsifiers, and in the body phospholipids are part of cell membranes. Sterols include cholesterol, bile, vitamin D, and some hormones. Animal-derived foods are high sources of cholesterol.

LEARN IT - 5.1 Recognize the chemistry of fatty acids and triglycerides and differences between saturated and unsaturated fats.

The predominant lipids both in foods and in the body are TRIGLYCERIDES (a molecule of glycerol with three/tri fatty acids attached). Fatty acids vary in the length of their carbon chains, their degrees of unsaturation (number of double bonds), and the location of their double bond(s). Those that are fully loaded with hydrogens are saturated: those that are missing hydrogens and therefore have double bonds are unsaturated (monounsaturated and polyunsaturated). The vast majority of triglycerides contain more than one type of fatty acid. Fatty acid saturation affects fats' physical characteristics and storage properties. Hydrogenation, which converts polyunsaturated fats to saturated fats, protects fats from oxidation and alters the texture by making liquid vegetable oils more solid. In the process, hydrogenation creates trans-fatty acids that damage health in ways similar to those of saturated fatty acids.

LEARN IT - 5.6 Explain the relationship between monounsaturated and polyunsaturated fats and health, not recommendations.

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LEARN IT - 5.5 Explain the relationships among saturated fats, trans fat, and cholesterol and chronic diseases, noting recommendations.

Although some fat in the diet is necessary, too much fat adds localities without nutrients, which leads to obsetity and nutrient inadequacies. Too much saturated fat, trans fat, and cholesterol increases the risk of heart disease and possibly cancer. For these reasons, health authorities recommend a diet moderate in total fat and low in saturated fat, trans fat

16a) What are the dietary recommendations regarding saturated fat and cholesterol intake?

Consume less than 10 percent of kcalories from saturated fat. Consume less than 300 milligrams per day of dietary cholesterol. Keep trans-fat consumption as low as possible by limiting foods that contain synthetic sources of trans fats, such as partially hydrogenated oils, and by limiting other solid fats.

5.3

Digestion, Absorption, and Transport of Lipids (pp. 142-147)

13) Which of the following is NOT true? Fats:

Do not contain glucose

5.6

Health Effects and Recommended Intakes of Monounsaturated and Polyunsaturated Fats (pp. 153-162)

5.5

Health Effects and Recommended Intakes of Saturated Fats, Trans Fats, and Cholesterol (pp. 150-152)

LEARN IT - 5.4 Outline the major roles of fats in the body, including a discussion of essential fatty acids and the omega fatty acids.

In the body, triglycerides provide energy, insulate against temperature extremes, protect against shock, provide structural material for cell membranes, and participate in cell signaling pathways. Linoleic acid (18 carbons/Omega-6) and linolenic acid (18 carbons/Omega-3) are essential fatty acids. They serve as structural parts of cell membranes and as precursors to the longer fatty acids that can make eicosanoids (powerful compounds that participate in blood pressure regulation, blood clot formation, and the immune response to injury and infection. Because essential fatty acids are common in the body, deficiencies are unlikely. The body can easily store unlimited amounts of fat if given excesses, and this body fat is used for energy when needed.

9) Which of the following is NOT true? Lecithin is:

Not an essential nutrient

1b) What are some of their functions in the body?

Provide energy, insulate against temperature extremes, protect against shock, and help the body use carbohydrates and proteins efficiently

5.1

The Chemist's View of Fatty Acids and Triglycerides (pp. 134-140)

5.2

The Chemist's View of Phospholipids and Sterols (pp. 140-141)

LEARN IT - 5.3 Summarize fat digestion, absorption, and transport.

The body makes special arrangements to digest and absorb lipids. It provides the emulsifier bile to make them accessible to the fat-digesting lipases that dismantle triglycerides, mostly to monoglycerides and fatty acids, for absorption by the intestinal cells. Four types of lipoproteins transport all classes of lipids- (triglycerides, phospholipids, and cholesterol), but the chylomicrons are the largest and contain mostly triglycerides from the diet; VLDL are smaller and are about half triglycerides; LDL are smaller still and contain mostly cholesterol; and HDL are the densest and are rich in protein. High LDL cholesterol indicates increased risk of heart disease, whereas high HDL cholesterol has a protective effect.

1a)Name three classes of lipids found in the body and in foods.

Triglycerides (3 fatty acids attached to glycerol by way of condensation reactions) Phospholipids (lecithin) Sterols (cholesterol)

6) Saturated fatty acids:

are fully loaded with hydrogens