Chapter 12, Problem 11RQ

The monomers that make up proteins are called_____. a. nucleotides b. disaccharides c. amino acids d. chaperones

What is the role of minerals in maintaining good health?

Explain the role of bile salts and lecithin in the emulsification of lipids (fats).

How can the ingestion of food increase the body temperature?

What regulatory processes would your body use if you were trapped by a blizzard in an unheated, uninsulated cabin in the woods?

Describe the four levels of protein structure. How do a proteins side groups influence its interactions with other substances? What happens when a protein is denatured?

Effects of Dietary Fats on Lipoprotein Levels Cholesterol that is made by the liver or that enters the body from food does not dissolve in blood, so it is carried through the bloodstream by lipoproteins. Low-density lipoprotein (LDL) carries cholesterol to body tissues such as artery walls, where it can form deposits associated with cardiovascular disease. Thus, LDL is often called bad cholesterol. Highdensity lipoprotein (HDL) carries cholesterol away from tissues to the liver for disposal, so HDL is often called good cholesterol. In 1990, Ronald Mensink and Martijn Katan published a study that tested the effects of different dietary fats on blood lipoprotein levels. Their results are shown in Figure 2.23. In which group was the level of LDL (bad cholesterol) highest?

Effects of Dietary Fats on Lipoprotein Levels Cholesterol that is made by the liver or that enters the body from food does not dissolve in blood, so it is carried through the bloodstream by lipoproteins. Low-density lipoprotein (LDL) carries cholesterol to body tissues such as artery walls, where it can form deposits associated with cardiovascular disease. Thus, LDL is often called bad cholesterol. Highdensity lipoprotein (HDL) carries cholesterol away from tissues to the liver for disposal, so HDL is often called good cholesterol. In 1990, Ronald Mensink and Martijn Katan published a study that tested the effects of different dietary fats on blood lipoprotein levels. Their results are shown in Figure 2.23. Figure 2.23 Effect of diet on lipoprotein levels. Researchers placed 59 men and women on a diet in which 10 percent of their daily energy intake consisted of cis fatty acids, trans fatty acids, or saturated fats. Blood LDL and HDL levels were measured after three weeks on the diet; averaged results are shown in mg/dL (milligrams per deciliter of blood). All subjects were tested on each of the diets. The ratio of LDL to HDL is also shown. Source, Mensink RP, Katan MB, Effect of dietary trans fatty acids on high-density and low-density lipoprotein cholesterol levels in healthy subjects. NEJM 323(7):43945. An elevated risk of heart disease has been correlated with increasing LDL-to-HDL ratios. Rank the three diets according to their predicted effect on cardiovascular health.

Chewing a bite of bread mixes it with saliva and facilitates its chemical breakdown. This is most likely due to the fact that ________. the inside of the mouth maintains a very high temperature chewing stores potential energy chewing facilitates synthesis reactions saliva contains enzymes