Enter a player name to begin or load your saved progress.
Basal Metabolic Rate (BMR) quantifies the energy expenditure of an animal exclusively during periods of rest and inactivity.
Answer: False
Explanation: Basal Metabolic Rate (BMR) measures the energy expenditure of an animal only when it is at rest and inactive, not during active physical engagement.
For an accurate Basal Metabolic Rate (BMR) measurement, the subject must be in a post-absorptive state, which implies they have fasted for a sufficient period prior to measurement.
Answer: True
Explanation: The post-absorptive state, meaning the absence of recent food consumption and active digestion, is a critical condition for accurate Basal Metabolic Rate (BMR) measurement.
Standard Metabolic Rate (SMR) is the term applied to ectothermic (bradymetabolic) animals, such as reptiles and fish, whereas Basal Metabolic Rate (BMR) is used for endothermic (warm-blooded) animals like mammals and birds.
Answer: True
Explanation: Standard Metabolic Rate (SMR) is the term used for ectothermic animals, while Basal Metabolic Rate (BMR) applies to endothermic animals, with SMR requiring specific temperature documentation.
Which of the following conditions is NOT listed as required for an accurate Basal Metabolic Rate (BMR) measurement?
Answer: Subject must have recently consumed a high-calorie meal.
Explanation: An accurate BMR measurement requires the subject to be in the post-absorptive state, meaning they have fasted, not recently consumed a large meal.
What is the fundamental definition of Basal Metabolic Rate (BMR)?
Answer: The rate at which an animal expends energy per unit of time while at rest.
Explanation: Basal Metabolic Rate (BMR) is defined as the minimum energy expenditure required to maintain essential bodily functions at complete rest.
Which of the following conditions is NOT listed as required for an accurate Basal Metabolic Rate (BMR) measurement?
Answer: Subject must have recently consumed a high-calorie meal.
Explanation: Accurate BMR measurement requires the post-absorptive state, meaning fasting, not recent consumption of a high-calorie meal.
What is the term equivalent to BMR for bradymetabolic animals, and what additional data is required for its measurement?
Answer: Standard Metabolic Rate (SMR); documentation of ambient temperature.
Explanation: Standard Metabolic Rate (SMR) is the term used for bradymetabolic animals, requiring the documentation of ambient temperature in addition to BMR criteria.
What is the primary distinction between Basal Metabolic Rate (BMR) and Resting Metabolic Rate (RMR) as described?
Answer: RMR uses less strict criteria than BMR but aims to approximate it.
Explanation: Basal Metabolic Rate (BMR) requires more stringent conditions than Resting Metabolic Rate (RMR), though RMR is intended to approximate BMR.
In humans, Basal Metabolic Rate (BMR) typically decreases by approximately 1-2% per decade after the age of 20, primarily due to a reduction in lean body mass.
Answer: True
Explanation: Basal Metabolic Rate (BMR) generally declines with age in humans, typically by 1-2% per decade after age 20, largely due to a decrease in lean body mass.
Increasing muscle mass is generally associated with an increase in an individual's Basal Metabolic Rate (BMR).
Answer: True
Explanation: Increasing muscle mass positively influences an individual's Basal Metabolic Rate (BMR), as muscle tissue is metabolically more active than adipose tissue.
Research from the 1990s indicated that aerobic fitness levels do not show a significant correlation with Basal Metabolic Rate (BMR) when adjusted for fat-free body mass.
Answer: True
Explanation: Research conducted in the 1990s suggested that aerobic fitness levels did not correlate with Basal Metabolic Rate (BMR) when adjusted for fat-free body mass.
In menstruating females, Basal Metabolic Rate (BMR) tends to increase during the luteal phase, influenced by hormonal fluctuations.
Answer: True
Explanation: During the luteal phase of the menstrual cycle, increased progesterone levels typically cause a rise in Basal Metabolic Rate (BMR).
A significant decrease in food intake typically leads to a decrease in the body's metabolic rate as a mechanism for energy conservation.
Answer: True
Explanation: When food intake significantly decreases, the body conserves energy by lowering its metabolic rate.
According to a 2012 study, aerobic training was found to be more effective than resistance training for reducing fat mass in overweight adults.
Answer: True
Explanation: A 2012 study indicated that aerobic training demonstrated greater efficacy than resistance training in reducing fat mass among overweight adults.
When food intake significantly decreases, the body conserves energy by lowering its metabolic rate.
Answer: True
Explanation: A substantial reduction in food intake typically triggers a decrease in metabolic rate as the body conserves energy resources.
What is the primary factor cited for the decline in human Basal Metabolic Rate (BMR) observed after the age of 20?
Answer: Decreased muscle mass (fat-free mass).
Explanation: The decline in human Basal Metabolic Rate (BMR) with age after 20 is primarily attributed to the associated loss of lean body mass (muscle).
Which of the following factors is identified as influencing an individual's Basal Metabolic Rate (BMR)?
Answer: Environmental temperature.
Explanation: Environmental temperature is one of several factors, alongside genetics, body composition, and hormonal status, that can influence an individual's Basal Metabolic Rate (BMR).
How does an increase in muscle mass typically affect an individual's Basal Metabolic Rate (BMR)?
Answer: It increases BMR.
Explanation: Increasing muscle mass generally leads to a higher Basal Metabolic Rate (BMR) because muscle tissue is metabolically more active than fat tissue.
According to research from the 1990s, what correlation exists between aerobic fitness and Basal Metabolic Rate (BMR) when adjusted for fat-free body mass?
Answer: No significant correlation.
Explanation: Research from the 1990s indicated no significant correlation between aerobic fitness levels and Basal Metabolic Rate (BMR) when adjusted for fat-free body mass.
What did a 2012 study find regarding the comparative effectiveness of aerobic versus resistance training for reducing fat mass in overweight adults?
Answer: Aerobic training was more effective for reducing fat mass.
Explanation: A 2012 study concluded that aerobic training was more effective than resistance training for reducing fat mass in overweight individuals.
How does a significant decrease in food intake typically affect an individual's metabolic rate?
Answer: It lowers metabolic rate to conserve energy.
Explanation: A significant reduction in food intake typically leads to a decrease in metabolic rate as the body conserves energy.
The Basal Metabolic Rate accounts for a significant portion of an individual's daily energy expenditure, making up approximately 70% of the total calories burned.
Answer: True
Explanation: Basal Metabolic Rate (BMR) constitutes approximately 70% of an individual's total daily energy expenditure, reflecting the energy required for basic physiological functions.
The original Harris-Benedict equation, published in 1919, used body mass (m), height (h), and age (a) to estimate total heat production (P) at complete rest, with different formulas for men and women.
Answer: True
Explanation: The original Harris-Benedict equation utilized body mass, height, and age, with sex-specific variations, to estimate basal heat production.
The Mifflin St Jeor equation, developed in 1990, estimates resting energy expenditure (P) using mass (m), height (h), and age (a), with a sex-specific constant (s, +5 for males, -161 for females).
Answer: True
Explanation: The Mifflin St Jeor equation estimates resting energy expenditure using mass, height, and age, incorporating sex-specific constants.
The Katch-McArdle formula estimates resting daily energy expenditure (RDEE) using lean body mass (l) in kilograms, with the formula P = 370 + 21.6 * l.
Answer: True
Explanation: The Katch-McArdle formula estimates resting daily energy expenditure (RDEE) based on lean body mass, calculated from total mass and body fat percentage.
Early research by Harris and Benedict indicated that expressing metabolic rate per unit of lean body mass helped to eliminate observed sex differences.
Answer: True
Explanation: Early studies by Harris and Benedict suggested that normalizing metabolic rate by lean body mass reduced or eliminated sex-based differences, implying similar metabolic intensity.
The revised Harris-Benedict equation is considered more accurate than the original equation due to its basis in more recent population data.
Answer: True, it uses updated population data.
Explanation: The revised Harris-Benedict equation, developed later, is generally considered more accurate as it incorporates more contemporary data compared to the original equation.
Approximately what proportion of an individual's total daily energy expenditure is typically accounted for by Basal Metabolic Rate (BMR)?
Answer: 70%
Explanation: Basal Metabolic Rate (BMR) typically accounts for about 70% of an individual's total daily energy expenditure.
The original Harris-Benedict equation estimated Basal Metabolic Rate (BMR) using which primary variables?
Answer: Body mass, height, age, and sex.
Explanation: The original Harris-Benedict equation utilized body mass, height, age, and sex as primary variables for estimating Basal Metabolic Rate (BMR).
What is the formula for the Mifflin St Jeor equation, where P represents energy expenditure, m is mass, h is height, and a is age?
Answer: Both A and B are correct depending on sex.
Explanation: The Mifflin St Jeor equation provides separate formulas for males and females: P = (10.0m + 6.25h - 5.0a + 5) for males and P = (10.0m + 6.25h - 5.0a - 161) for females.
What is a primary limitation of Basal Metabolic Rate (BMR) estimation formulas such as the Harris-Benedict and Mifflin St Jeor equations?
Answer: They are primarily based on total body mass, not lean mass.
Explanation: A key limitation of formulas like Harris-Benedict and Mifflin St Jeor is their reliance on total body mass, not fully accounting for the metabolic differences of lean body mass versus fat mass.
Thermogenesis refers to the body's process of generating heat, which is a component of energy expenditure.
Answer: True
Explanation: Thermogenesis is the physiological process by which the body generates heat, contributing to its overall energy expenditure.
According to the provided table, the brain consumes the largest percentage of energy expenditure among listed organs.
Answer: False
Explanation: The provided data indicates the liver consumes the largest percentage of energy expenditure (27%), followed by the brain (19%) and skeletal muscle (18%).
The Respiratory Quotient (R.Q.) for the complete oxidation of glucose is approximately 1.0.
Answer: True
Explanation: The Respiratory Quotient (R.Q.) for glucose oxidation is 1.0 because the ratio of carbon dioxide produced to oxygen consumed is equal (6 CO2 / 6 O2).
The Respiratory Quotient (R.Q.) for palmitic acid, a saturated fatty acid, is approximately 0.696.
Answer: True
Explanation: The Respiratory Quotient (R.Q.) for palmitic acid is calculated as 16 CO2 / 23 O2, resulting in approximately 0.696.
Protein catabolism can supply a notable portion of energy requirements during prolonged exercise (exceeding two hours).
Answer: True
Explanation: During prolonged exercise, protein catabolism is estimated to supply between 10% to 15% of the total energy requirement.
At rest, what is the primary fuel source utilized for ATP production?
Answer: Fats (70%)
Explanation: At rest, the body primarily utilizes fats for ATP production, accounting for approximately 70% of the energy source, with carbohydrates making up the remaining 30%.
Adenosine Triphosphate (ATP) stores energy in its chemical bonds and releases it to drive endergonic cellular processes.
Answer: True
Explanation: Adenosine Triphosphate (ATP) functions as the primary energy currency of the cell, storing energy in its phosphate bonds for release to power cellular activities.
According to the provided data, which organ consumes the largest percentage of total energy expenditure?
Answer: Liver
Explanation: The liver accounts for the largest proportion of energy expenditure among the listed organs, consuming approximately 27% of the total.
What is the Respiratory Quotient (R.Q.) for the complete oxidation of glucose?
Answer: 1.0
Explanation: The Respiratory Quotient (R.Q.) for the complete oxidation of glucose is 1.0, reflecting an equal ratio of CO2 produced to O2 consumed.
What is the Respiratory Quotient (R.Q.) for palmitic acid, a saturated fatty acid?
Answer: 0.696
Explanation: The Respiratory Quotient (R.Q.) for palmitic acid is approximately 0.696, calculated from its oxidation equation.
During prolonged exercise (exceeding two hours), what percentage of the energy requirement might protein catabolism supply?
Answer: 10-15%
Explanation: Protein catabolism is estimated to contribute approximately 10% to 15% of the energy requirement during extended periods of exercise (over two hours).
What is the significance of Adenosine Triphosphate (ATP) in driving cellular processes?
Answer: It transfers energy from exergonic reactions to power cellular work.
Explanation: Adenosine Triphosphate (ATP) is significant because it transfers energy released from exergonic reactions to power endergonic cellular work.
What does the term 'postprandial thermogenesis' refer to?
Answer: The increase in metabolic rate after consuming food.
Explanation: Postprandial thermogenesis refers to the increase in metabolic rate that occurs following the consumption of food.
What is the approximate breakdown of total daily energy expenditure into its primary components?
Answer: Basal processes 70%, Physical activity 20%, Thermogenesis 10%
Explanation: Total daily energy expenditure is approximately divided into basal processes (70%), physical activity (20%), and thermogenesis (10%).
The hypothalamus, a region of the brain, is identified as the primary organ responsible for regulating metabolism, including autonomic functions and body temperature.
Answer: True
Explanation: The hypothalamus serves as the central regulator of metabolism, overseeing autonomic functions, body temperature, and appetite control.
Antithyroid agents, such as methimazole, are prescribed to decrease metabolic rate in individuals with hyperthyroidism.
Answer: True
Explanation: Antithyroid medications like methimazole are used to manage hyperthyroidism by reducing the body's metabolic rate.
The hypothalamus plays a crucial role in regulating metabolism, including the control of body temperature.
Answer: True
Explanation: The hypothalamus is integral to metabolic regulation, influencing processes such as body temperature control and autonomic functions.
The hypothalamus regulates food intake through complex mechanisms, not solely by sensing blood glucose levels.
Answer: True
Explanation: While blood glucose levels play a role, the hypothalamus regulates food intake via multiple signals, including hormonal and neural inputs, not solely glucose sensing.
How does the menstrual cycle typically influence Basal Metabolic Rate (BMR) in females?
Answer: BMR rises during the luteal phase due to progesterone.
Explanation: During the luteal phase, hormonal changes, specifically increased progesterone, typically cause a rise in Basal Metabolic Rate (BMR) in females.
Which physiological organ is identified as the primary regulator of metabolic processes?
Answer: The hypothalamus
Explanation: The hypothalamus is recognized as the primary physiological organ responsible for regulating metabolism.
Antithyroid agents, such as methimazole, are medically used to:
Answer: Decrease metabolic rate in hyperthyroidism.
Explanation: Antithyroid agents like methimazole are used to reduce metabolic rate in conditions such as hyperthyroidism.
Which of the following represents a primary function of the hypothalamus in regulating metabolism?
Answer: Regulating body temperature.
Explanation: A primary function of the hypothalamus in metabolism is the regulation of body temperature.
The satiety center within the hypothalamus is stimulated by:
Answer: High levels of leptin.
Explanation: The satiety center in the hypothalamus is stimulated by factors such as high levels of leptin, signaling fullness.
What is the role of the hypothalamus in the regulation of food intake?
Answer: It contains centers that initiate hunger and satiety signals.
Explanation: The hypothalamus contains critical centers that initiate and regulate hunger and satiety signals, thereby controlling food intake.
The Variable Maximum Model (VMM) suggests that maximum metabolic rate is constant, while sustained metabolism becomes a larger fraction of it in response to cold.
Answer: False
Explanation: The Variable Maximum Model (VMM) posits that maximum metabolic rate increases in response to cold, while the Variable Fraction Model (VFM) suggests maximum metabolism is constant but sustained metabolism increases as a fraction of it.
Raymond Pearl's 'rate of living hypothesis' proposed that longevity is inversely proportional to basal metabolic rate.
Answer: True
Explanation: Raymond Pearl's 'rate of living hypothesis' suggested that organisms with lower basal metabolic rates tend to have longer lifespans.
Calorie restriction is generally associated with decreased metabolic rates and has been linked to increased longevity in animals.
Answer: True
Explanation: Calorie restriction often leads to reduced metabolic rates and has been associated with increased longevity in various animal models.