Human Physiology and Food Energy

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How long does it take for energy balance related to caloric consumption to appear based on habitual caloric intake?

5 to 7 weeks prior

1 to 3 weeks prior (correct)

2 to 4 weeks prior

4 to 6 weeks prior

What happens when there are sudden dietary and activity changes in relation to adiposity stores?

Gradual reduction in adiposity stores

Immediate increase in adiposity stores

Immediate reduction in adiposity stores

No immediate effect on adiposity stores (correct)

What is the result of physiological systems being exposed to dramatically reduced caloric consumption?

Increase energy expenditure and reduce fat storage

Break down muscle tissue and prioritize fat storage (correct)

Enhance muscle mass and reduce fat storage

Reduce muscle tissue and enhance fat storage

How long does it take for energy balance related to physical activity to exhibit a time-lagged effect based on habitual physical activity behaviors?

2 to 8 weeks prior Signup and view all the answers

What happens when an individual becomes trapped and is unable to secure a source of food?

Calories consumed go to zero Signup and view all the answers

What is a common observation related to failures in the implementation of the energy balance framework?

Too large of an energy imbalance was created Signup and view all the answers

What happens to the metabolic rate if an individual does not exert physical activity when attempting to free themselves?

It will continue churning through stored energy sources until death. Signup and view all the answers

Why is muscle breakdown advantageous during times of starvation?

It results in metabolic slowing, preserving fat stores. Signup and view all the answers

How does the body allocate energy when in a state of starvation?

Preferentially towards fat storage. Signup and view all the answers

What are some challenges associated with maintaining energy balance according to the text?

Physiological systems being hard-wired for survival. Signup and view all the answers

Based on early research findings, when are survival mechanisms like metabolic slowing brought online?

When calories consumed fall below 1.2× basal metabolic rate. Signup and view all the answers

What is one protective mechanism mentioned in the text related to additional fat stores?

Energy buffer. Signup and view all the answers

What is a food calorie in scientific terms?

A kilocalorie Signup and view all the answers

How is caloric content of food measured using a calorimeter?

By measuring the change in temperature in the water surrounding the food container after ignition Signup and view all the answers

What unit reflects the amount of energy needed to raise the temperature of one kilogram of water by one degree Celsius?

Kilocalorie Signup and view all the answers

Which system uses established energetic values for energy-containing nutrients rather than direct calorimetric measurements?

The Atwater indirect system Signup and view all the answers

What term is typically used for a kilocalorie within the U.S.?

'Calorie' Signup and view all the answers

How is a known quantity of food tested for its caloric content using a calorimeter?

By burning it in an oxygen-rich container and measuring the temperature change in the surrounding water Signup and view all the answers

What is the impact of inaccurate reporting of caloric intake on energy balance?

Energy balance starts to suffer Signup and view all the answers

How does muscle mass change affect metabolic rate?

Muscle mass decrease leads to increased metabolic rate Signup and view all the answers

What is an issue if an individual uses an inaccurate metabolic rate estimate formula?

Poor fit for the individual Signup and view all the answers

How do smartphone and smartwatch technologies contribute to estimating physical activity-related energy expenditure?

Increase accuracy compared to self-reporting practices Signup and view all the answers

What can happen if energy balance approaches do not regularly revise metabolic contributions?

They suffer in their predictive capacity Signup and view all the answers

How does inaccurate identification of activities by smartphones or smartwatches affect caloric expenditure reports?

Results in misreporting of caloric expenditure Signup and view all the answers

What is the purpose of the Atwater indirect system of food labeling?

To assign a caloric value to food Signup and view all the answers

Which term refers to how close measurements of the same item are to each other?

Precision Signup and view all the answers

What is the main challenge with caloric reporting of dietary practices?

Obtaining accurate numbers Signup and view all the answers

Why is there considerable variation in the caloric content of food, especially in less processed items?

Error in food composition Signup and view all the answers

What does the energy balance equation require in order to work properly?

Accurate numbers Signup and view all the answers

How does the Atwater indirect system help assign caloric values to food?

By knowing the mass and composition of food Signup and view all the answers