ch 22

A harmful substance that the liver produces when metabolizing fatty acids is A) ammonia. B) urea. C) ketone bodies. D) rancid fatty acids. E) beta units.

C

Gluconeogenesis refers to A) converting glucose to glycogen storage. B) removing glucose from storage as glycogen. C) creating glucose from glycerol, amino acids, or lactate. D) converting glucose to storage as adipose tissue. E) removing fatty acids from adipose storage.

C

In type I diabetes, a hyperglycemic hyperosmotic state may occur. Which of the following best describes this state? A) There are low levels of vasopressin (ADH). B) There is decreased water intake. C) Plasma glucose and blood osmolarity levels are above normal. D) ATP production is increased due to the increased levels of glucose. E) Blood osmolarity is below normal levels due to elevated glucose.

C

Insulin secretion A) is stimulated by sympathetic neurons. B) decreases in response to elevated amino acid concentrations. C) is stimulated by parasympathetic neurons. D) is inhibited by GLP-1. E) None of these answers are correct.

C

Match each term to its definition. A. anabolism B. biochemical pathway C. catabolism reactions that result in breakdown of large molecules

C

Match the nutrient to its primary fate. A. carbohydrate B. protein C. fat storage

C

Match the term to its definition. A. metabolism B. catabolism C. anabolism large molecules synthesized from smaller ones

C

The brain neurotransmitter that is an important stimulus for food intake is A) ghrelin. B) leptin. C) neuropeptide Y. D) orexin. E) insulin.

C

The feeding and satiety centers are located in the A) medulla oblongata. B) pons. C) hypothalamus. D) cerebrum. E) cerebellum.

C

The liver and skeletal muscles store glucose as ________ for a ready energy source. A) lipids B) glucose C) glycogen D) urea E) ketone bodies

C

The nutrients that yield the most energy per gram when metabolized are A) carbohydrates. B) proteins. C) fats. D) nucleic acids. E) vitamins.

C

When blood glucose levels rise, as in the "fed" state, A) only insulin is released. B) only glucagon is released. C) only peripheral cells take up less glucose. D) only protein synthesis decreases. E) All of these answers are correct.

A

When blood glucose levels fall, A) only insulin is released. B) only glucagon is released. C) only peripheral cells take up less glucose. D) only protein synthesis decreases. E) All of these answers are correct.

B

Which is NOT produced in the body for the purpose of storing extra calories? A) fat B) protein C) carbohydrate D) All of these are produced in the body for that purpose.

B

tabolism is a term that describes A) all work done by a living organism. B) all chemical reactions that take place within an organism. C) only chemical reactions that release ATP from living cells. D) the energy released from chemical bonds in living cells. E) the extraction of nutrients from biomolecules

B

________ is a condition of insulin deficiency from beta cell destruction

type ii diabetes mellitus

Drugs used to treat diabetes may A) stimulate beta-cell secretion of insulin. B) stimulate digestion and absorption of carbohydrates in the intestine. C) stimulate hepatic glucose output. D) decrease responsiveness of target tissue to insulin. E) None of these answers are correct

A

During the absorptive state, A) the liver forms glycogen. B) adipocytes contribute fatty acids to the circulation. C) skeletal muscles break down glycogen. D) glucagon levels are elevated. E) All of these answers are correct.

A

In the fasted state, which of the following statements is FALSE? A) Skeletal muscle will increase gluconeogenesis. B) Pyruvate and lactate are transported to liver to make glucose. C) Some amino acids will be deaminated. D) Adipose breaks down its store of triglycerides

A

Match each term to its definition. A. anabolism B. biochemical pathway C. catabolism reactions that result in the synthesis of large molecules

A

Match the nutrient to its primary fate. A. carbohydrate B. protein C. fat used immediately for energy

A

Pre-diabetes is a condition that will likely become diabetes if eating and exercise habits are not altered. A) True B) False

A

The beta cells of the pancreas produce A) insulin. B) glucagon. C) renin. D) cortisol. E) digestive enzymes.

A

The level of ketone bodies in the blood increases when high levels of ________ are being metabolized. A) fatty acids B) glucose C) proteins D) amino acids E) carbohydrates

A

Describe a ketogenic diet. What are the pros and cons of such a diet? How is ketosis related to diabetes mellitus?

A ketogenic diet is low in carbohydrate and high in protein and fat. Ketone bodies are produced as fat is metabolized. Pros: rapid initial weight loss and caloric restriction. Cons: initial weight loss represents loss of glycogen and water, rather than fat; dehydration, vitamin and mineral deficiency; and kidney problems. Untreated diabetics cannot metabolize carbohydrates normally, so their diets are functionally ketogenic.

The Atkins and South Beach diets are considered ketogenic because A) Type I diabetics use them. B) they cause the body to burn calories from non-carbohydrate sources. C) they shift one's metabolism to increased levels of glycolysis. D) they have the potential to increase the body's pH. E) they require people to eat large quantities of ketones

B

The alpha cells of the pancreas produce A) insulin. B) glucagon. C) renin. D) cortisol. E) digestive enzymes.

B

The brain relies solely on ________ as its energy source. If it is deprived of this substrate, the cells soon die. A) fatty acids B) glucose C) amino acids D) insulin

B

Compare and contrast insulin and glucagon

Answers will vary but should include information in Tables 22.1 and 22.3 in the chapter.

) A primary target tissue for insulin is the A) brain only. B) liver only. C) intestine only. D) brain and liver. E) brain, liver, and intestine.

B

An enzyme that digests fats is A) hydrolase. B) lipase. C) lyase. D) ligase. E) kinase.

B

Both insulin and glucagon are peptide hormones that target liver cells. The responses of the target cells to these two hormones are exactly the opposite of each other. This information implies that A) one hormone binds to a receptor on the cell membrane and the other to an intracellular receptor. B) each of the two hormones uses a different second messenger. C) both hormones interact with receptors at the cell nucleus. D) one of the hormones does not interact with a membrane receptor.

B

During starvation, A) carbohydrate utilization increases. B) gluconeogenesis accelerates. C) there is a decline in circulating ketone bodies. D) structural proteins cannot be used as a potential energy source. E) All of these answers are correct.

B

During the fasting state, the energy stores of the ________ become the major source of glucose for the whole body. A) brain B) liver C) muscles D) pancreas E) adipose tissues

B

In type 2 diabetes, insulin levels are frequently normal, yet the target cells are less sensitive to the effects of insulin. This suggests that the target cells A) are impermeable to insulin. B) may have a defect in their signal transduction pathway. C) cannot convert insulin to an active form. D) have adequate internal supplies of glucose. E) None of these answers are correct.

B

Match each term to its definition. A. anabolism B. biochemical pathway C. catabolism series of interconnected chemical reactions

B

Match the nutrient to its primary fate. A. carbohydrate B. protein C. fat synthesis of tissues

B

Match the term to its definition. A. metabolism B. catabolism C. anabolism large molecules broken into smaller ones

B

Specific responses to changes in body temperature are regulated by the A) thermoreceptors. B) hypothalamus. C) medulla oblongata. D) skin. E) cardiac output.

B

When amino acids are metabolized for energy, the nitrogen is converted to urea and then is excreted from the body by the A) liver. B) skin. C) kidneys. D) sweat glands. E) spleen.

C

When blood levels of glucose, amino acids, and insulin are high, and glycogenesis is occurring in the liver, the body is in the A) fasting state. B) postabsorptive state. C) absorptive state. D) stress state. E) bulimic state.

C

Glucagon A) only stimulates gluconeogenesis. B) primarily targets the liver. C) primarily targets skeletal muscle. D) stimulates gluconeogenesis and primarily targets the liver. E) stimulates gluconeogenesis and primarily targets skeletal muscle.

D

If you were in a desert without a food source, which nutrient would you like to have stored in your body in a large amount? A) protein B) glycogen C) calcium D) fat E) vitamin B6

D

The reactions where fats are broken down into glycerol and fatty acids are called A) glycerolysis. B) glycolysis. C) gluconeogenesis. D) lipolysis. E) liposuction.

D

The synthesis of glucose from a noncarbohydrate precursor is referred to as A) glycogenesis. B) glycogenolysis. C) glycolysis. D) gluconeogenesis. E) glycogen.

D

) GLUT4 transporters are A) only stored in cytoplasmic vesicles. B) only inserted in response to glucagon. C) only inserted into the plasma membrane by endocytosis. D) only found in adipose and skeletal muscles. E) stored in cytoplasmic vesicles and found in adipose and skeletal muscles.

E

After ingestion of carbohydrates in an insulin-deficient diabetic, ________ would happen. A) protein degradation B) fat synthesis C) ketone production D) glycolysis E) protein degradation and ketone production

E

Anabolism is a term that describes A) reactions that release energy. B) reactions that require a net input of energy. C) reactions that result in the synthesis of large biomolecules. D) reactions that release energy and reactions that result in the synthesis of large biomolecules. E) reactions that require a net input of energy and reactions that result in the synthesis of large biomolecules.

E

Dehydration can result from A) heat exhaustion. B) CCK. C) diabetes. D) gluconeogenesis. E) heat exhaustion and diabetes.

E

Insulin A) only stimulates glycolysis. B) only stimulates lipogenolysis. C) only inhibits gluconeogenesis. D) stimulates glycolysis and lipogenolysis. E) stimulates glycolysis and inhibits gluconeogenesis

E

On a tour of African countries, Don contracts a bad case of traveler's diarrhea. Because he can't eat very much, his body starts to use energy sources other than carbohydrates. This would result in A) increased levels of urea in the blood. B) ketosis. C) a decreased blood pH. D) increased gluconeogenesis in the liver. E) All of these answers are correct.

E

The brain can use ________ for energy. A) only glucose B) only fats C) only ketones D) only lactate E) both glucose and ketones

E

Which of the following symptoms would you expect to observe in a person suffering from type I diabetes mellitus? A) glucosuria B) ketoacidosis C) thirst and polydipsia D) hyperglycemia E) All of these answers are correct.

E

Prior to the discovery of the role of insulin in metabolism and the development of insulin therapy to treat diabetes mellitus, a diagnosis of this disease was always fatal. What do untreated diabetics die from?

Figure 22.20 in the chapter provides a good summary of the effects of untreated diabetes mellitus. Metabolic acidosis and circulatory failure from dehydration are the primary triggers of death.

Explain why glucose or other simple sugars should NOT be the sole source of energy in our diets. What is the best approach to meeting energy needs?

Given that glucose only meets energy rather than other essential nutrient needs, a person consuming only glucose would die of malnutrition. A mixture of fats, proteins, simple sugars, and complex carbohydrates optimizes the storage, nutrient, and caloric needs of the various organ systems. Glucose requires a relatively large amount of water for hydration and a large amount of space for storage. Glycogen is more compact, and fat is the most compact and efficient means of energy storage.

Why does insulin deficiency lead to metabolic acidosis?

Insulin deficiency produces a fasted-state metabolism. The liver metabolizes fatty acids for its energy needs, producing ketones. The ketones enter the blood, then are absorbed by tissues and converted to acetyl CoA. Ketones themselves are strong acids, thus ketoacidosis results. Other tissues begin to produce lactic acid, due to their anaerobic state resulting from loss of access to glucose.

High protein (low carbohydrate) diets have become popular in recent years. Based on what you've learned about metabolism and the body's energy needs, explain what might be some of the disadvantages of this type of diet.

Low carbohydrate diets shift the body to a fasting mode because glucose is needed for the brain, central nervous systems, and red blood cells. After glycogen stores have been depleted, the body will convert protein and fats into glucose and ketone bodies to provide the energy needed. The disadvantages of this shift are excess ketone bodies can seriously disrupt the body's pH balance (lead to ketosis) and loss of protein from body tissue (this occurs even when abundant protein from food is provided).

Sandy has insulin-dependent diabetes mellitus. Sandy has an accident on his bike and breaks his arm. Would his insulin dosage change?

Sandy will need increased levels of insulin. Insulin will promote the necessary healing by supporting anabolic reactions needed for regrowth of the bone. Students will learn in chapter 23 that prolonged stress (rather than the stress just at the time of the accident) will lead to increased blood glucose levels due to increased cortisol secretion, hence additional insulin will be needed to compensate for this as well.

________ is known as insulin-resistant diabetes

Type 2 diabetes

Compare and contrast the two types of diabetes mellitus

Type I diabetes mellitus is a condition of insulin deficiency due to pancreatic beta cell destruction. Type 2 diabetes mellitus is insulin-resistant, due to a variety of causes. Figure 22.20 in the chapter provides a detailed summary of the characteristics of type I diabetes

It is known that exercise is good for diabetics. Explain how GLUT4 transporters may be involved in this beneficial effect of exercise

When one exercises, skeletal muscles are utilized. Once they are active, they no longer require insulin to be able to take up glucose from the blood. This is due to the fact that exercise causes more GLUT4 transporters to be inserted into the membrane of the muscle cells. Thus, exercise is able to remove the excess glucose from the bloodstream of diabetics

Metabolism is often divided into ________, energy-producing reactions, and ________, energy-utilizing reactions.

catabolism, anabolism

The process of glycogen formation is known as ________.

glycogenesis

The pancreatic hormone that raises blood glucose concentration is ________.

glucagon

The process of synthesizing glucose from lipids, amino acids, or other carbohydrates is called ________.

gluconeogenesis

Lipids are broken down into ________, which feeds into glycolysis, and ________, which are metabolized to acetyl CoA

glycerol, fatty acids

The combination of type 2 diabetes, atherosclerosis, and high blood pressure is called ________.

metabolic syndrome

Match the term to its definition. A. metabolism B. catabolism C. anabolism the sum of all the body's chemical reactions

metabolism

The loss of water in the urine due to unreabsorbed solutes is known as ________.

osmotic diuresis