Question 1

Cold cereal is often fortified with all sorts of vitamins and minerals but is deficient in the amino acid lysine. How might this deficiency be compensated for?

Accepted Answer

All of the above options would provide a source of lysine to compensate for the deficiency in cold cereal. Peanut butter and beans are both good sources of lysine, and adding milk to cereal also provides some lysine. So, choosing all of the above options would ensure an adequate intake of lysine.

Question 2

Cellular respiration produces the same products as ________.

Accepted Answer

Cellular respiration produces ATP, carbon dioxide, and water, which are the same products produced by a campfire. Choice A is incorrect because catabolism is the process of breaking down molecules and can produce a variety of different products depending on the specific metabolic pathway. Choice B is incorrect because anabolism is the process of building molecules and would produce different products than cellular respiration. Choice C is incorrect because nucleic acids are not involved in cellular respiration.

Question 3

Which of the following statements about proteins is true?

Accepted Answer

The simpler an amino acid is, the more likely it is to be generated within the body.

Question 4

What is the role of soluble fiber in a well-balanced diet?

Accepted Answer

Soluble fiber absorbs water and forms a gel-like substance, which can help absorb toxins and cholesterol, aiding in their removal from the body.

Question 5

The general outcome of catabolism is ________.

Accepted Answer

Catabolism is the process of breaking down complex molecules into simpler ones. This results in the release of energy, which can be used by the cell for various metabolic processes. Therefore, the general outcome of catabolism is the tearing down of biomolecules. Option A is incorrect because anabolism is the process of building biomolecules. Option B is incorrect because cellular respiration is just one of the many metabolic processes that use the energy released by catabolism. Option D is incorrect because energy is released during catabolism, not formed catalytically.

Question 6

A friend of yours loads up on vitamin C once a week instead of spacing it out over time. She argues the convenience of not having to take pills every day. What advice do you have for her?

Accepted Answer

Vitamin C is a water soluble vitamin, which means it doesn't get stored in the body for future use, so it is necessary to take it regularly to maintain its levels. Taking a large dose once a week wouldn't be more beneficial, and excess vitamin C is excreted in the urine.

Question 7

What is the main compound formed in the digestion of carbohydrates?

Accepted Answer

Glucose is the main compound formed in the digestion of carbohydrates. Carbohydrates are broken down into simpler sugars during digestion, and glucose is the most common and important simple sugar that is extracted from the food we eat. Glucose is then used by the body for energy or stored for later use in the form of glycogen.

Question 8

Which will satisfy your hunger for a longer period of time?

Accepted Answer

Spaghetti has a lower glycemic index (GI) compared to the other options, meaning it will be broken down and absorbed by the body slower, which can keep you feeling fuller for a longer period of time. Foods with a lower GI are generally better choices for satiety and weight management.

Question 9

Suggest why the glycemic index for sucrose is only about 64 percent that of glucose.

Accepted Answer

Sucrose is a disaccharide made up of one glucose and one fructose molecule. When sucrose is digested, it is cleaved into its component glucose and fructose molecules. Therefore, the glycemic index of sucrose is lower than that of glucose, which is a monosaccharide and can be absorbed more readily by the body.

Question 10

Which of the following statements is true about metabolism?

Accepted Answer

Metabolism encompasses both the breakdown of molecules to produce energy (catabolism) and the use of energy to construct new molecules (anabolism), as well as processes like cellular respiration that affect the rate of these reactions.

Question 11

The general outcome of anabolism is ________.

Accepted Answer

Anabolism is the process of building complex molecules from simpler ones, which leads to the synthesis of biomolecules such as proteins, carbohydrates, and lipids. Therefore, the general outcome of anabolism is the building of biomolecules.

Question 12

The human body stores excess glucose as glycogen and excess fat as fatty tissue that can accumulate beneath the skin. How does the body store any excess amino acids?

Accepted Answer

Excess amino acids can be used in the synthesis of various proteins in the body, such as muscle tissue, collagen, and keratin. They are not stored in the body like glucose or fat, but are utilized for various cellular processes.

Question 13

Mammals cannot produce polyunsaturated fatty acids. How is it then that the lard obtained from beef fat contains up to 10 percent polyunsaturated fatty acids?

Accepted Answer

Cows obtain polyunsaturated fatty acids from their diet, which consists mainly of plant materials that contain these fatty acids.

Question 14

Peanut butter has more protein per gram than a hard-boiled egg, and yet the egg represents a better source of protein. Why?

Accepted Answer

The essential amino acids are the ones that our body cannot produce on its own and must be obtained through our diet. The proteins in eggs have a better balance of these essential amino acids, making them a higher quality source of protein even though they have less protein overall compared to peanut butter.

Question 15

Which statement is more accurate? a. Vitamins are needed by the body to avoid vitamin-deficiency diseases, such as scurvy.
B. Vitamins are needed by the body so that many of its catabolic and anabolic reactions can proceed efficiently.

Accepted Answer

Vitamins are essential for numerous biochemical reactions in the body, including both catabolic and anabolic processes, making statement b more comprehensive and accurate.

Question 16

Metabolism includes ________.

Accepted Answer

Metabolism includes both catabolism (the breakdown of molecules to release energy) and anabolism (the building up of molecules). Cellular respiration is also part of metabolism, as it involves the conversion of glucose and oxygen into energy (ATP) for the cell. Therefore, all of the choices are included in metabolism.

Question 17

Which of the following statements is true about fats in the diet?

Accepted Answer

Saturated fats are used to make cholesterol, which is important for several bodily functions but too much can increase the risk of heart disease. It is recommended to limit saturated fat intake and replace with unsaturated fats. B, C, and D are all false statements. Saturated fats can increase LDL (bad) cholesterol levels and are not healthier than unsaturated fats. Unsaturated fats do not produce arterial plaque.

Question 18

Suggest why starch takes longer to break down to glucose in the intestine than does sucrose.

Accepted Answer

Starch is composed of many glucose units bonded together in chains, and enzymes that break down starch can only access the ends of these chains to release glucose. Sucrose, on the other hand, is a disaccharide composed of glucose and fructose, and is broken down more quickly by digestive enzymes.

Quiz 13: Nutrients of Life