Question 1

To obtain the most accurate measure of resting metabolic rate in healthy adults, before beginning an indirect calorimetry procedure, the subject should abstain from moderate aerobic or anaerobic exercise for at least 2 hours

Accepted Answer

This is true because engaging in moderate exercise prior to the measurement can elevate metabolic rate and result in an inaccurate reading. It is also recommended to avoid consuming caffeine or nicotine and to fast for several hours prior to the measurement for the most accurate result.

Question 2

When thyroid hormones are elevated above normal concentrations, RMR is abnormally low.

Accepted Answer

When thyroid hormones are elevated above normal concentrations, RMR is abnormally high, not low. Thyroid hormones play a major role in regulating metabolism and increasing RMR, so an excess of these hormones will lead to an increase in RMR.

Question 3

It is estimated that sedentary people use about ____ kilocalories of energy per kilogram body weight daily.

Accepted Answer

The answer of It is estimated that sedentary people use...

Question 4

The thick contractile protein of a muscle cell is known as ____.

Accepted Answer

Myosin is the thick contractile protein found in muscle cells. Actin is the thin contractile protein that interacts with myosin during muscle contractions. Troponin and tropomyosin are regulatory proteins that are also involved in muscle contractions, but are not the thick contractile proteins.

Question 5

Which statement is true when people are asked to keep a food diary?

Accepted Answer

Athletes may consciously or unconsciously undereat due to a focus on maintaining a certain body weight or composition, which can lead to inaccurate food diary entries.

Question 6

The terms calorie and Calorie can be used interchangeably in scientific writing.

Accepted Answer

The term calorie (lowercase "c") is used in scientific contexts to refer to the amount of energy required to raise the temperature of one gram of water by one degree Celsius. The term Calorie (uppercase "C") is used in nutrition to refer to the kilocalorie, which is equal to 1000 calories. Using these terms interchangeably can lead to confusion and inaccuracies in scientific writing.

Question 7

Resting metabolism comprises approximately 50 percent of a sedentary person's total daily energy expenditure.

Accepted Answer

Resting metabolism, or basal metabolic rate (BMR), comprises approximately 60-75% of a sedentary person's total daily energy expenditure, depending on their age, sex, weight, and body composition.

Question 8

ATP is critical for muscle contraction, but it is not involved in skeletal muscle relaxation.

Accepted Answer

ATP is involved in both muscle contraction and relaxation. During muscle relaxation, ATP is involved in the release of calcium ions from the muscle fibers, which is necessary for the muscle to relax.

Question 9

It is estimated that sedentary people use about 30 kilocalories of energy per kilogram body weight daily.

Accepted Answer

This statement is true. Sedentary people use about 30 kilocalories of energy per kilogram body weight daily. However, this is just an estimate and the actual energy expenditure can vary depending on various factors like age, gender, muscle mass, and metabolism.

Question 10

During a muscle contraction, what happens immediately after calcium binds to troponin?

Accepted Answer

When calcium binds to troponin, it causes a conformational change that moves tropomyosin away from the binding sites on actin, allowing myosin to form crossbridges and begin the power stroke. Therefore, choice B is the correct answer as it describes the immediate action of calcium binding to troponin.

Question 11

Physical activity may comprise only approximately ____ percent of the sedentary person's daily energy expenditure.

Accepted Answer

The answer of Physical activity may comprise only approximately ____...

Question 12

As the body utilizes the potential energy contained in food, a large portion of that energy is converted to heat energy.

Accepted Answer

This is true. When the body breaks down food, energy is released and a portion of that energy is converted into heat, which helps to regulate body temperature. This is why we feel warm and may even sweat after eating a large meal or exercising.

Question 13

The Compendium of Physical Activities expresses the energy expended in ____.

Accepted Answer

The Compendium of Physical Activities expresses the energy expended in metabolic equivalents (METs), which is a unit of measurement that reflects the amount of energy expended by an individual during physical activity compared to their resting metabolic rate. It is not expressed in kilojoules, calories or kilocalories.

Question 14

The greatest source of error when using a food diary is the accurate recording of both the types and amounts of foods and beverages consumed.

Accepted Answer

The accurate recording of both the types and amounts of foods and beverages consumed is crucial in obtaining valid data from a food diary. However, other sources of error may include forgetfulness, underestimation, overestimation, and misinterpretation of the recorded data.

Question 15

What contributes the smallest amount of energy expended over a 24-hour period?

Accepted Answer

The thermic effect of food contributes the smallest amount of energy expended over a 24-hour period. This refers to the energy used by the body to digest, absorb and metabolize the food we eat, which ranges from 5-10% of total energy expenditure. Resting metabolism, basal metabolic rate, and physical activity all contribute significantly more to energy expenditure.

Question 16

6,300 kJ = ____ kilocalories.

Accepted Answer

1 kcal = 4.184 kJ
6300 kJ = 6300/4.184 kcal ≈ 1502 kcal ≈ 1500 kcal (rounded to the nearest whole number)

Question 17

The maintenance of the distribution of ions across cell membranes is an example of ____ work.

Accepted Answer

The distribution of ions across cell membranes creates an electrical potential difference, which requires work to maintain. This is an example of electrical work.

Question 18

The energy content of carbohydrates and proteins is estimated to be 9 kcal/g.

Accepted Answer

The energy content of carbohydrates and proteins is estimated to be approximately 4 kcal/g, while fats have about 9 kcal/g.

Question 19

Very low calorie "starvation" diets result in a reduced resting metabolic rate and can actually impede weight loss.

Accepted Answer

When the body is put on a very low calorie diet, it goes into a "starvation mode" and slows down the metabolism to conserve energy. This reduction in metabolism makes it harder for the body to burn calories and lose weight. In some cases, it can even cause the body to start breaking down muscle tissue for energy instead of fat. As a result, very low calorie diets are not recommended for long-term weight loss and should be approached with caution.

Question 20

The storage of carbohydrates by forming glycogen for later use is an example of ____ work.

Accepted Answer

The storage of carbohydrates as glycogen involves the chemical work of converting glucose molecules into a larger, more complex molecule (glycogen) that can be stored in cells for later use as an energy source. Electrical work involves the movement of charged particles, mechanical work involves the movement of physical objects, and transportation work involves the movement of molecules or other substances across a membrane or within a cell.

Quiz 2: Defining and Measuring Energy