Chapter 24: Metabolism and Nutrition

The molecule that serves as the major source of readily available fuel for neurons and blood cells is

________.

A) protein

B) acetyl CoA

C) glucose

D) fat

glucose

The most abundant dietary lipids are______.

A) cholesterol

B) fatty acids

C) phospholipids

D) triglycerides

triglycerides

Which of the choices below is not a fate of carbohydrate taken into the body?

A) ATP production

B) glycogenesis

C) lipogenesis

D) direct conversion to a nucleic acid

E) amino acid synthesis

direct conversion to a nucleic acid

Which hormone directs essentially all the events of the absorptive state?

A) epinephrine

B) thyroid hormone

C) insulin

D) growth hormone

insulin

When a person's hypothalamic thermostat is set to a higher level and the actual body temperature is below that level, the person may ________.

A) exhibit vasodilation of skin vessels

B) pant

C) perspire heavily

D) shiver

shiver

Which of the following is correct?

A) Each FADH2 yields about 1 1/2 ATP via oxidative phosphorylation.

B) Most ATP from cellular respiration are produced directly in the Krebs cycle.

C) Most of the ATP are produced by substrate-level phosphorylation.

D) Glycolysis relies on substrate-level oxidation for the four ATP produced in this pathway.

Each FADH2 yields about 1 1/2 ATP via oxidative phosphorylation

Which of the following does not occur in the mitochondria?

A) formation of malic acid from fumaric acid

B) glycolysis

C) Krebs cycle

D) electron transport

glycolysis

Which of the following is a normal consequence of the activation of the heat-promoting center?

A) vasodilation of cutaneous blood vessels

B) sympathetic sweat gland activation

C) increase in ADH production

D) release of epinephrine

release of epinephrine

The term basal metabolic rate reflects the ________.

A) energy the body needs to perform only its most essential activities

B) energy needed to make all organic molecules

C) loss of organic molecules in urine

D) loss of energy to perspiration

energy the body needs to perform only its most essential activities

Which of the choices below is not a source of glucose during the postabsorptive state?

A) absorption of glucose from the GI tract

B) lipolysis in adipose tissues and the liver

C) catabolism of cellular protein

D) glycogenolysis in the liver

absorption of glucose from the GI tract

Which of the following is the major role of leptin in the body?

A) decrease appetite and food intake

B) protect against weight loss during nutritional deprivation

C) promote weight loss with activity

D) shrink fat stores

protect against weight loss during nutrition deprivation

Which of the following best defines negative nitrogen balance?

A) Protein breakdown exceeds protein synthesis.

B) A negative nitrogen balance is normal and is a way of maintaining homeostasis.

C) It is a condition usually caused by having a diet low in fish and meat.

D) It occurs when amino acids are broken down by liver enzymes and carried to the

bloodstream.

Protein breakdown exceeds protein synthesis

Transamination is the process whereby the amine group of an amino acid is ________.

A) converted to ammonia

B) transferred to acetyl CoA

C) converted to urea

D) transferred to a keto acid

transferred to a keto acid

Oxidative deamination takes place in the ________.

A) liver

B) brain

C) muscles

D) blood

liver

What process primes a molecule to change in a way that increases its activity, produces motion, or does work?

A) beta oxidation

B) phosphorylation

C) glycolysis

D) cellular respiration

phosphorylation

Prostaglandins play a role in ________.

A) control of blood volume

B) noninflammatory responses

C) skeletal muscle contraction

D) control of blood pressure

control of blood pressure

The process of breaking triglycerides down into glycerol and fatty acids is known as ________.

A) lipolysis

B) lipogenesis

C) gluconeogenesis

D) fat utilization

lipolysis

Oxidation reduction reactions ________.

A) occur via the gain of hydrogen or the loss of oxygen

B) are rarely coupled together

C) may involve the loss of hydrogen and electrons

D) utilize hydrogenases

may involve the loss of hydrogen and electrons

Select the correct statement about proteins.

A) Proteins will be used by most cells for ATP synthesis if insufficient carbohydrates are

ingested.

B) Strict vegetarians need not worry about adequate protein intake, as most vegetables are

almost perfect sources of amino acids.

C) Proteins can be synthesized in the body if most of the amino acids are present.

D) Catabolic steroids (hormones) accelerate the rate of protein synthesis.

Proteins will be used by most cells for ATP synthesis if insufficient carbohydrates are ingested

Heat-loss mechanisms do not include ________.

A) vasoconstriction of peripheral blood vessels

B) behavior measures such as wearing light, loose clothing

C) the evaporation of sweat

D) reducing activity

vasoconstriction of peripheral blood vessels

Cholesterol, though it is not an energy molecule, has importance in the body because it ________.

A) helps mobilize fats during periods of starvation

B) enters the glycolytic pathway without being altered

C) helps provide essential nutrients to the brain and lungs

D) is a stabilizing component of the plasma membranes and is the parent molecule of steroid

hormones

is a stabilizing components of the plasma membranes and is the parents molecule of steroid hormones

Which of the following food groups are considered good sources of complete proteins?

A) egg yolk, fish roe, and grains

B) corn, cottonseed oil, soy oil, and wheat germ

C) lima beans, kidney beans, nuts, and cereals

D) eggs, milk, yogurt, meat, and fish

eggs, milk, yogurt, meat, and fish

Which food type is considered to be the most important for athletes to eat to improve performance?

A) animal proteins

B) complex carbohydrates

C) plant proteins

D) simple sugars

complex carbohydrates

Which of the choices below is not a mechanism of heat production? 24)

A) sweating

B) shivering

C) enhanced thyroxine release

D) vasoconstriction of cutaneous blood vessels

sweating

In the liver, the amine group of glutamic acid is removed as ________ in the oxidative state.

A) oxaloacetic acid

B) glyceraldehyde

C) pyruvic acid

D) ammonia

ammonia

When ketone bodies are present in the blood and urine in large amounts, it usually indicates increased metabolism of ________.

A) glycogen

B) amino acids

C) fatty acids

D) lactic acid

fatty acids

Catabolism would be best described as a process that ________.

A) builds up triglycerides during the postabsorptive state

B) breaks down complex structures to simpler ones

C) elevates glucagon levels

D) causes a decline in circulating ketone bodies

breaks down complex structures to simpler ones

he primary reason elderly people should decrease their caloric intake is that ________.

A) their appetite begins to diminish

B) they have a higher metabolic rate and do not need large amounts of food

C) muscle mass and metabolism decline with age

D) they spend most of the day at rest, and their food will quickly turn to fat

muscle mass and metabolism decline with age

Conditions that promote the oxidative deamination and energy use of amino acids include ________.

A) adequate fat calories to provide adequate ATP formation

B) ammonia combining with oxygen to form urea

C) adequate essential amino acids

D) excessive amounts of protein in the diet

excessive amounts of protein in diet

In gluconeogenesis, during the postabsorptive state, amino acids and ________ are converted to glucose.

A) glycogen

B) acetyl Co A

C) glycerol

D) glucagon

glycerol

Which of the following mechanisms produces the most ATP during cellular respiration?

A) lactic acid production

B) oxidative phosphorylation

C) oxidation reactions

D) substrate-level phosphorylation

oxidative phosphorylation

Which of the choices below describes the pathway of cellular respiration (the complete oxidation of glucose)?

A) lipolysis, glycogenolysis, beta oxidation

B) glycolysis, Krebs cycle, electron transport chain, oxidative phosphorylation

C) gluconeogenesis, Krebs cycle, lipolysis

D) glycogenesis, lipogenesis, electron transport chain

glycolysis, Krebs cycle, electron transport chain, oxidative phosphorylation

Many factors influence BMR. What is the most critical factor?

A) the ratio of surface area to volume (weight) of the body

B) an individual's body weight

C) the way an individual metabolizes fat

D) the way skeletal muscles break down glycogen

the ratio of surface area to volume (weight) of the body

Gluconeogenesis is the process in which ________.

A) glucose is formed from noncarbohydrate precursors

B) glycogen is broken down to release glucose

C) glucose is converted into carbon dioxide and water

D) glycogen is formed

glucose is formed from noncarbohydrate precursors

Which of the following is not an important function of the liver?

A) synthesis of vitamin K

B) protein metabolism

C) carbohydrate and lipid metabolism

D) synthesis of bile salts

protein metabolism

As the body progresses from the absorptive to the postabsorptive state, only the ________ continues to burn glucose while every other organ in the body mostly switches to fatty acids.

A) pancreas

B) liver

C) spleen

D) brain

brain

Glucose can be obtained from ________.

A) glycogenolysis

B) lipogenesis

C) protein anabolism

D) triglyceride anabolism

glycogenolysis

Which of the following nutrients yield the highest amount of energy per gram when metabolized?

A) proteins

B) fats

C) vitamins and minerals

D) foods and beverages high in caffeine

fats

Anabolism includes reactions in which ________.

A) ketone bodies are formed

B) structural proteins are used as a potential energy source

C) larger molecules or structures are built from smaller ones

D) carbohydrate utilization increases

larger molecules or structures are built from smaller ones

Lipogenesis occurs when ________.

A) cellular ATP and glucose levels are high

B) glucose levels drop slightly

C) there is a shortage of fatty acids

D) excess proteins are transported through the cell membrane

cellular ATP and glucose levels are high

The amount of ________ produced is probably the most important hormonal factor in determining BMR.

A) ADH

B) thyroxine

C) norepinephrine

D) prolactin

thyroxine

Which of the following statements is a false or incorrect statement?

A) Fats and carbohydrates are oxidized directly to produce cellular energy.

B) Amino acids can be used to supply energy only after being converted to a carbohydrate

intermediate.

C) Excess carbohydrate and fat can be stored as such, whereas excess amino acids are oxidized

for energy or converted to fat or glycogen for storage.

D) The amino acid pool is the body's total supply of amino acids in the body's proteins.

The amino acid pool is the body's total supply of amino acids in the body's proteins.

The primary function of cellular respiration is to ________.

A) break down food molecules and generate ATP

B) provide the body with adequate amounts of vitamins and minerals

C) efficiently monitor the energy needs of the body

D) determine the amount of heat needed by the human body

break down food molecules and generate ATP

What is the outcome of ketosis?

A) glucogenesis

B) metabolic acidosis

C) metabolic alkalosis

D) water retention and edema

E) glycogen buildup

metabolic acidosis

Which of the following is not true of beta oxidation?

A) It occurs in the mitochondrion.

B) Every second carbon is reduced.

C) Fatty acids are broken into acetic acid fragments.

D) It involves the anabolism of fats.

It involves the anabolism of fats.

The ingestion of which nutrient type results in the greatest food-induced thermogenesis?

A) proteins

B) carbohydrates

C) lipids

D) vitamins

proteins

Which of the following is not a function of LDLs?

A) regulate cholesterol synthesis in tissue cells

B) transport cholesterol from the peripheral tissues to the liver

C) make cholesterol available to tissue cells for membrane or hormone synthesis

D) assist in the storage of cholesterol when supply exceeds demand

transport cholesterol from the peripheral tissues to the liver

Minerals required by the body in moderate amounts include all but which of the following?

A) sodium and chlorine

B) iron and selenium

C) sulfur and potassium

D) calcium and phosphorus

B) iron and selenium

The term metabolism is best defined as ________.

A) the length of time it takes to digest and absorb fats

B) the sum of biochemical reactions involved in building breaking down molecules

C) a measure of carbohydrate utilization, typically involving measurement of calories

D) the number of calories it takes to keep from shivering on a cold day

the sum of biochemical reactions involved in building breaking down molecules

When proteins undergo deamination, the waste substance found in the urine is mostly ________.

A) ketone bodies

B) ammonia

C) acetyl CoA

D) urea

urea

Glycolysis is best defined as a catabolic reaction based upon the ________.

A) conversion of glucose into carbon dioxide and water

B) conversion of pyruvic acid into carbon dioxide and water

C) formation of sugar

D) conversion of glucose into two molecules of pyruvic acid

conversion of glucose into two molecules of pyruvic acid

It is important to ensure that your diet is adequately rich in vitamins because ________.

A) vitamins provide protection against the common cold

B) all vitamins are water soluble and pass out of the body too quickly to ensure utilization

C) most vitamins are coenzymes needed to help the body utilize essential nutrients

D) very few foods contain vitamins

most vitamins are coenzymes needed to help the body utilize essential nutrients

Which of the following statements best describes complete protein?

A) derived only from legumes and other plant material

B) must contain all the body's amino acid requirements for maintenance and growth

C) derived from meat and fish only

D) meets all the minimum daily requirements for a healthy diet

must contain all the body's amino acid requirements for maintenance and growth

Which of the choices below is not a major route of heat exchange?

A) evaporation

B) radiation

C) conduction/convection

D) shivering

shivering

In the case of a person who consumes a normal, balanced diet, proteins are essential to the body for all of the following except ________.

A) formation of functional molecules like hemoglobin and cytochromes

B) production of energy

C) production of some hormones

D) production of enzymes, clotting factors, and antibodies

production of energy

Glycogen is formed in the liver during the ________.

A) absorptive state

B) starvation period

C) postabsorptive state

D) period when the metabolic rate is lowest

absorptive state

Which of the choices below happens during the absorptive state?

A) Only glucose metabolism occurs.

B) Catabolic processes exceed anabolic ones.

C) No metabolism occurs.

D) Anabolic processes exceed catabolic ones.

Anabolic processes exceed catabolic ones.