Module 3 Flashcards
(28 cards)
Define metabolism
- Metabolism: the sum total of all the chemical rxns occurring in an organism
Define BMR
the stable rate of E metab measured under conditions of minimum environmental and physiological stress
what is direct calorimetry
measuring metabolic rate of an organism by measuring the amount of energy released as heat over a given period
Why is direct calorimetry not a good technique
- and imprecise for animals w/ low metabolic rate and large animals would need huge chambers
- Animals’ normal behaviour and metabolism are constrained by measurement conditions
How is indirect calorimetry used
-Material dried out, placed in ignition chamber, developed in jacket w/ known amount of h2o, burned to ash w/ o2 gas and resulting heat is captured by surrounding water jacket, E released determined by temp increase of H2O
What is respirometry
Metabolic rate being measured by oxygen uptake (MO2) and carbon dioxide produced (MCO2), expressed as moles of gas per hour
Why is fat the most effective form of energy storage
- Fat is the most effective form of energy storage because oxidation of fat yields twice the yield per gram of carbohydrates
- fat is stored in dehydrated form, takes up less space, whereas carbohydrates are stored in bulky hydrated form
What are the disadvantages of using fat for energy
it takes long to hydrolyze and prepare for use for energy
How does weight increase relate the surface area increase?
The change in weight is usually greater than the change in surface area.
How is mass-specific metabolic rate and body mass related
Inversely related
Do larger or smaller animals have the higher mass-specific metabolic rate?
Smaller animals
How does body size relate to metabolic rate vs. mass-specific metabolic rate?
- Overall metabolic rate rises with increasing body size, whereas mass-specific metabolic rate decreases with increasing body size
What does muscular effort contribute to during locomotion?
- production of forward momentum
- hold limb joints in their proper positions
- counteract gravity
- absorb shocks
- oppose movements of antagonistic muscles
How can we measure metabolism during locomotion?
- Measurements of O2 consumption and CO2 production are made while an animal is running on a treadmill, swimming in a flow tank, or flying in a wind tunnel
- Measured rate of gas exchange is translated into rate of energy conversion
what does catabolism do
breaks down complex, energy-rich molecules into simple ones, releasing energy
what does anabolism do
uses energy to assemble simple substances into more complex molecules required by the organism
define SMR
standard metabolic rate: an animal’s resting and fasted metabolism at a given body temperature
define FMR
field metabolic rate: avg. metab rate as an animal undergoes “normal” activities under “normal” conditions
define metabolic scope
the ratio of the maximum sustainable metabolic rate to the BMR determined under controlled, resting conditions
what does Hess’ law state
total E released in breakdown of a fuel to a given set of end products is always the same, irrespective of the intermediate chemical steps or pathways used
how does isotopic technique measure metabolism
The animal is captured and injected with water in which the hydrogen and oxygen are isotopically “labelled” . The difference between the loss of labeled oxygen and hydrogen over time gives us the amount of CO2 lost and provides a measure of metabolism
which animal will respire at higher rates/body mass: elephant or gerbil?
gerbil (small animal)
What’s the metabolic cost of locomotion
The metabolic cost of locomotion is the amount of energy required to move a unit mass of animal a unit distance
It takes more effort for larger or smaller animals to achieve a given speed?
Larger. Small animals possess less inertia, and so require little energy utilization to accelerate, Large animals are slow to get moving
