AskSia

Plus

what factors affect metabolic rate

Feb 27, 2024

what factors affect metabolic rate

Answer

Factors that affect metabolic rate include age, sex, body size, body composition, genetic factors, hormonal levels, physical activity, and environmental temperature.

Solution

Age: Metabolic rate generally decreases with age due to loss of muscle mass and changes in cellular processes

Sex: Males often have a higher metabolic rate than females because they typically have more muscle mass and less body fat

Body Size and Composition: Larger individuals and those with more muscle mass have higher metabolic rates because muscle tissue is more metabolically active than fat tissue

Genetic Factors: Variations in genes can influence metabolic rate by affecting the efficiency of metabolic processes

Hormonal Levels: Hormones such as thyroxine and adrenaline can increase metabolic rate by stimulating metabolic activity

Physical Activity: Exercise raises metabolic rate during and after the activity due to increased energy demands and muscle repair processes

Environmental Temperature: Both extreme cold and extreme heat can raise metabolic rate as the body works to maintain a stable internal temperature

Key Concept

Metabolic rate is influenced by a combination of physiological, genetic, and environmental factors.

Explanation

These factors can either increase or decrease the rate at which the body converts food into energy, thus affecting overall metabolism.

The figure below represents differences in metabolic rate in relation to body size of four vertebrate groups namely placental mammals, marsupials, passerine birds and non-passerine birds. Study this figure and provide answers to the questions that follow. 3.1. Match the four vertebrate groups (placental mammals, marsupials, passerine birds and non-passerine birds) to the letters indicated on the figure (e.g. A = ; B = …etc.) (4) 3.2. Provide appropriate axes titles for the figure. Note that the axes values reported are log10-transformed. (2) 3.3. Provide a single appropriate equation to describe the broad relationship depicted in the figure. The values in your equation do not need to be exact, but should approximate the overall trend. (2) 3.4. Draw a diagram to illustrate what you’d expect to see if the values on both axes were not log10-transformed. (2) QUESTION 4 [5] Make use of a simple diagram (that you draw yourself) to illustrate the flow of air through the lungs of birds. QUESTION 5 [10] Briefly describe, using bullet points, the three main approaches to determine the metabolic rates of animals. -1,5 -1 -0,5 0 0,5 1 1,5 2 2,5 3 -1 -0,5 0 0,5 1 1,5 2 2,5 3 3,5 A B C D

Answer

Without the figure, I cannot provide specific matches or titles.

Solution

Without the figure, it is not possible to provide appropriate axes titles

A general equation for metabolic rate (MR) in relation to body mass (M) on a log-log scale could be:

MR = aM^b

where

a

is the y-intercept and

b

is the slope of the line

Without the figure, it is not possible to draw a diagram of the non-log-transformed values

Key Concept

Metabolic rate and body mass relationship

Explanation

The metabolic rate of an organism is often related to its body mass in a non-linear fashion, which can be described by a power-law equation on a log-log scale.

Answer

A diagram illustrating the flow of air through the lungs of birds cannot be drawn without visual tools.

Solution

Key Concept

Bird respiratory system

Explanation

Birds have a unique respiratory system that allows for a continuous flow of air through their lungs, enhancing gas exchange efficiency.

Answer

The three main approaches to determine the metabolic rates of animals are:

Solution

Indirect calorimetry: Calculating metabolic rate from the oxygen consumption and/or carbon dioxide production

Doubly labeled water: Using isotopes to measure CO2 production in free-living animals over a period of time

Key Concept

Determining metabolic rates

Explanation

Metabolic rates can be measured using direct calorimetry, indirect calorimetry, or the doubly labeled water method, each providing insights into the energy expenditure of animals.