Metabolism!

________ is a substance in food used by the body to promote normal growth, maintenance, and repair.

A nutrient

Which of the following is not a characteristic of glycolysis?

Glycolysis is an aerobic process

______ is considered "good" cholesterol; high blood levels of this cholesterol are thought to be beneficial

HDLs

Select the correct statement about proteins.

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

Cholesterol

Serves as a precursor to hormones and maintains the fluidity of the plasma membrane

Which of the following is a characteristic of the electron transport chain (ETC)?

The ETC occurs in the mitochondria.

Which of the following is a characteristic of the Krebs cycle?

The Krebs cycle generates a rich supply of the reduced coenzymes, NADH and FADH2

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

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

Glycogenolysis

The cleavage of glycogen to release glucose

Glycogenesis

The formation of glycogen to store glucose

Gluconeogenesis

The process of forming new glucose from noncarbohydrate molecules

Beta oxidation

The start phase of fatty acid breakdown

Lipogenesis

Triglyceride synthesis

Fat-soluble vitamins can be toxic if consumed in large quantities

True

The body is able to form glucose from noncarbohydrate precursors

True

Protein

Used to build enzymes

Which of the following is a water-soluble vitamin?

Vitamin B

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

absorption of glucose from the GI tract

Glycogen is formed in the liver during the ________.

absorptive state

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

ammonia

As proteins are broken down for energy______ is generated; the liver then converts this potentially toxic intermediate into______.

ammonia; urea

Redox reactions:

are characterized by one substance gaining an electron while another substance loses an electron.

Conversion of fatty acids into acetyl groups.

beta oxidation

The term metabolism is best defined as ________.

biochemical reactions involved in building cell molecules or breaking down molecules for energy

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

brain

The primary function of cellular respiration is to ________.

break down food molecules and generate ATP

Catabolism would be best described as a process that ________.

breaks down complex structures to simpler ones

Lipogenesis occurs when ________.

cellular ATP and glucose levels are high

Prostaglandins play a role in ________.

control of blood pressure

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

conversion of glucose into two molecules of pyruvic acid

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

conversion to a nucleic acid

Glycolysis occurs in the ______ of cells and is an _______ process.

cytosol; anaerobic

Oxidation-reduction reactions are catalyzed by which of the following enzymes?

dehydrogenases and oxidases

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

eggs, milk, yogurt, meat, and fish

The term metabolic rate reflects the ________.

energy the body needs to perform only its most essential activities

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

excessive amounts of protein in the diet

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

fats

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

fatty acids

Formation of glucose from proteins or fats.

gluconeogenesis

Neurons and red blood cells rely exclusively on ________ to meet their energy needs.

glucose

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

glucose

Gluconeogenesis is the process in which ________.

glucose is formed from noncarbohydrate precursors

Which of the following molecules are considered key molecules at metabolic crossroads?

glucose-6-phosphate, pyruvic acid, acetyl CoA

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

glycerol

In the postabsorptive state

glycogen is broken down to release glucose

Storage of glucose in the form of glycogen

glycogenesis

Breakdown of glycogen to release glucose

glycogenolysis

Glucose can be obtained from ________.

glycogenolysis

Breakdown of glucose to pyruvic acid.

glycolysis

Which of the following does not occur in the mitochondria?

glycolysis

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

glycolysis, Krebs cycle, electron transport chain, oxidative phosphorylation

Dietary fats are important because they ________.

help the body absorb fat-soluble vitamins

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

insulin

In the absorptive state

insulin serves as the regulatory hormone.

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

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

Formation of ketone bodies.

ketogenesis

Anabolism includes reactions in which ________.

larger molecules or structures are built from smaller ones

Synthesis of lipids from glucose or amino acids.

lipogenesis

Splitting of triglycerides into glycerol and fatty acids

lipolysis

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

lipolysis

Oxidative deamination takes place in the ________.

liver

The primary goal during the postabsorptive state is to:

maintain blood glucose levels within a homeostatic range.

Oxidation reduction reactions ________.

may involve the loss of hydrogen and electrons

What is the outcome of ketosis?

metabolic acidosis

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

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

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

muscle mass and metabolism decline with age

Which of the following statements best describes complete protein?

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

person who is starving is likely to exhibit:

negative nitrogen balance

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

oxidative phosphorylation

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

phosphorylation

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

production of energy

Which of the following is the most important function of the liver?

protein metabolism

Loss of heat in the form of infrared waves is termed ________.

radiation

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

release of epinephrine

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

shiver

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

shivering

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

sweating

Vitamins

Can function as coenzymes

_____ refers to reactions in which large molecules are broken down into smaller molecules.

Catabolism

Which of the following is an example of catabolism?

Cellular respiration

Which of the following is not an end product of the Krebs cycle?

Citric acid

A growing child is likely to exhibit negative nitrogen balance.

False

A substance that is reduced has lost an electron

False

Leptin is a short-term regulator of food intake.

False

Most ATP in cellular respiration is generated in glycolysis.

False

The body's overall rate of energy output is called the basal metabolic rate.

False

Glucose serves as the initial reactant.

Glycolysis

Occurs in the cytosol of a cell

Glycolysis

Mineral

An example is calcium

Which of the choices below happens during the absorptive state?

Anabolic processes exceed catabolic ones

Which of the following would raise body temperature?

Eating a large meal

Glucose

Exclusive energy source for neurons

_________ is the key hormone regulator of the absorptive state.

Insulin

Which of the following is not true of beta oxidation?

It involves the anabolism of fats.

Involves the removal of hydrogen electrons and CO2 from the substrate molecule.

Krebs cycle and electron transport chain

Produces the most ATP

Krebs cycle and electron transport chain

Involves the use of oxygen to pick up excess hydrogen and electrons.

Krebs cycle and electron transport chain.

______ are considered "bad" cholesterol; high blood levels are believed to increase the risk for cardiovascular disease.

LDLs

The final electron acceptor in the electron transport chain is _____.

O2

Which of the following best defines negative nitrogen balance?

Protein breakdown exceeds protein synthesis.

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

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

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

thyroxine

The body's rate of kilocalorie consumption needed to fuel all ongoing activities is called the:

total metabolic rate.

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

transferred to a keto acid

Which of the following is not a function of LDLs?

transport cholesterol from the peripheral tissues to the liver

The most abundant dietary lipids are ________.

triglycerides

When proteins undergo deamination, the waste substance found in the urine is mostly________

urea

Ammonia, which is a byproduct of protein metabolism, is converted to _____ in the ______.

urea; liver

Heat-loss mechanisms do not include ________.

vasoconstriction of peripheral blood vessels