Question 1

Infants with genetic disorders of metabolism need to use special formulas to ensure adequate nutrient intake.

Accepted Answer

Infants with genetic disorders of metabolism often cannot metabolize certain nutrients found in regular infant formulas or breast milk, necessitating the use of special formulas designed to meet their unique nutritional needs without exacerbating their condition.

Question 2

As soon as an infant who has a genetic disorder of metabolism begins to take solid food, a special diet must be followed until a new formula is prescribed during adolescence.

Accepted Answer

The need for a special diet in individuals with a genetic disorder of metabolism depends on the specific disorder and its management requirements, which can vary widely. Some may require lifelong dietary restrictions, while others might have different dietary needs during various stages of life, not just until adolescence.

Question 3

Most metabolic reactions take place in the mitochondria of cells.

Accepted Answer

Mitochondria are known as the "powerhouses of the cell" because they are responsible for generating most of the cell's energy through cellular respiration.

Question 4

Cells use ATP to provide energy for metabolic reactions.

Accepted Answer

ATP (Adenosine Triphosphate) serves as the primary energy carrier in cells, providing the necessary energy for various metabolic reactions and processes.

Question 5

ATP must be regenerated from ADP and phosphate (which can be donated by creatine phosphate) or produced during anaerobic metabolism, which can fuel the body for no more than 1.5 minutes, or aerobic metabolism, which can continue indefinitely.

Accepted Answer

ATP is regenerated from ADP and phosphate through processes like creatine phosphate donation and anaerobic or aerobic metabolism. Anaerobic metabolism is limited in duration, while aerobic metabolism can sustain energy production for extended periods.

Question 6

Hormones catalyze metabolic reactions with the aid of coenzymes, especially forms of niacin and riboflavin, as well as enzymes such as insulin, glucagon, epinephrine, and cortisol.

Accepted Answer

Hormones do not catalyze metabolic reactions themselves; they act as signaling molecules that regulate the activity of enzymes, which then catalyze metabolic reactions.

Question 7

Weight lifters rest in between sets to give the body time to form more ATP used for the next set of lifts.

Accepted Answer

Rest periods between sets allow for the replenishment of ATP (adenosine triphosphate), which is the primary energy source for muscle contractions during weight lifting.

Question 8

The high- energy molecule adenosine triphosphate (ATP) releases energy to be used by the cells when the phosphate bond is broken, producing adenosine diphosphate (ADP).

Accepted Answer

When ATP (adenosine triphosphate) undergoes hydrolysis, a phosphate bond is broken, releasing energy and resulting in the formation of ADP (adenosine diphosphate) and an inorganic phosphate. This process is fundamental for cellular energy transfer.

Question 9

Insulin and glucagon are produced in the pancreas, cortisol and epinephrine are produced in the adrenal glands.

Accepted Answer

Insulin and glucagon are hormones produced by the pancreas, while cortisol and epinephrine are hormones produced by the adrenal glands.

Question 10

When you need energy to do work, your body hydrolyzes one of the phosphate bonds, releasing one phosphate and a tremendous amount of energy.

Accepted Answer

When your body needs energy, it breaks down adenosine triphosphate (ATP) by hydrolyzing one of its phosphate bonds, releasing energy along with a molecule of adenosine diphosphate (ADP) and a free phosphate group. This process is fundamental for cellular energy transfer.

Question 11

With the release of one phosphate from ATP, a new molecule with only two phosphates is formed, adenosine diphosphate, or ADP. A phosphate group is added back to ADP to reform ATP during anabolism, a reaction that requires energy.

Accepted Answer

During anabolism, energy is indeed required to add a phosphate group back to ADP, forming ATP, which is a key process in cellular energy storage and release.

Question 12

Catabolic reactions require energy to build new substances whereas anabolic reactions break molecules apart, yielding energy.

Accepted Answer

Catabolic reactions break molecules apart, yielding energy, whereas anabolic reactions require energy to build new substances.

Question 13

Individuals who are deficient in niacin and riboflavin are likely to have very little energy and are likely to feel tired.

Accepted Answer

Niacin (Vitamin B3) and riboflavin (Vitamin B2) are essential for the body's energy production processes. Deficiencies in these vitamins can impair energy metabolism, leading to fatigue and low energy levels.

Question 14

During glycolysis, for example, glucose is oxidized to pyruvate and the coenzyme form of the B vitamin niacin (NAD+) is reduced to NADH + H+.

Accepted Answer

During glycolysis, glucose undergoes a series of enzymatic reactions that result in its oxidation to pyruvate. In this process, NAD+ (nicotinamide adenine dinucleotide), which is a coenzyme form of the B vitamin niacin, is reduced to NADH + H+, capturing energy from the glucose molecule that can be used later in cellular respiration to produce ATP.

Question 15

Creatine phosphate (PCr) is a compound that provides a reserve of phosphate to regenerate ADP to ATP.

Accepted Answer

Creatine phosphate (PCr) acts as an energy reserve in muscle cells by donating a phosphate group to ADP to regenerate ATP, which is the primary energy carrier in cells.

Question 16

Adenosine diphosphate (ADP) is a nucleotide which is composed of adenine, ribose, and two phosphate molecules, and it is formed when one phosphate molecule is removed from ATP.

Accepted Answer

ADP (Adenosine Diphosphate) is indeed formed from ATP (Adenosine Triphosphate) when one phosphate group is removed, typically through a process involving the hydrolysis of the terminal phosphate bond, releasing energy.

Question 17

Glycolysis transforms glucose to pyruvate.

Accepted Answer

Glycolysis is a metabolic pathway that converts glucose into pyruvate, producing ATP and NADH in the process.

Question 18

Ketogenic molecules cannot be transformed into ketone bodies.

Accepted Answer

Ketogenic molecules can indeed be transformed into ketone bodies, which is a process that occurs during the breakdown of fats and ketogenic amino acids in the liver.

Question 19

Glucogenic amino acids, glycogen, and glycerol can enter into anaerobic glycolysis at specific pathways to produce pyruvate.

Accepted Answer

Glucogenic amino acids and glycerol can be converted into intermediates that enter glycolysis, but glycogen is broken down into glucose-6-phosphate, which directly enters glycolysis. Anaerobic glycolysis specifically refers to the conversion of glucose to pyruvate, not the entry of other substrates.

Question 20

After the fat- soluble nutrients (vitamins A, D, E, K) have been absorbed through the small intestine, they can enter a metabolic pathway and be converted to energy or be stored as fat for later use.

Accepted Answer

Fat-soluble vitamins (A, D, E, K) are not typically used for energy production. Instead, they are stored in the liver and fatty tissues for later use and have various roles in the body, such as supporting immune function, vision, and blood clotting, rather than being converted to energy.

Quiz 8: Energy Metabolism