Chapter 7 Flashcards
What is high-grade energy ?
Energy able to perform work such as chemical (bond energy), electrical (membrane potential,action potential), mechanical (kinetic, gravitational potential).
What is low-grade energy?
Energy unable to perform work only molecular kinetic energy, heat that is the ultimate destiny for other energy form.
What factors affect metabolic rate in animals?
Body size,eating,exercise
Metabolic rate best measured by
Calorimetry- (Direct/Indirect) AKA material balance
Direct Calorimeter
measures heat leaving body
Indirect Calorimeter
measures rate of respiratory gas exchange w/ its environment & measures chemical- energy content of organic matter that enters/leaves the body.
-O2 consumption
Calculate Respiratory exchange ratio (R)
Foodstuff-RER
Carbs-1.0
Lipids-0.71
Protein-0.83
Interpret RER/ What measurements are required to calculate it ?
RER=moles of CO2 produced per unit time/ moles of O2 consumed per unit time -Req to cal 02 consumed CO2 produced glucose consumed
not isometric(straight line 1) w/ body weight but it is allometry, can calculate the metabolic rate per unit of body weight
weight specific metabolic rate
EXP=1
Isometry
exp>1
positive allometry
exp
negative allometry
BMR and SMR relation?
- measured while the animal is resting/fasting
- exercise produces metabolic rate increase
- feeding causes metabolic rate increase(SDA)
Basal metabolic rate (BMR)
used for homothermic animals, measured at their thermoneutral zone,or the temp range in which it is minimal
Standard metabolic rate (SMR)
used for poikilothermic animals and is specific to the temp at which it is measured, many SMR for a given individual.
Multiple underlying causes theory
-rates of underlying biochemical processes (rate of ATP production) interact to produce a common “organisimal” scaling relationship
What theoretical explans the accommadates difference to allometric slope in exercising vs resting animals
multiple underlying causes theory
What theroretical explains the scaling of metabolic rate as combined effects of underlying process
multiple underlying causes
Energy
capacity to do mechanical work, measured as the product of force and distance or capacity to increase order.
heat- random atomic molecular motion
molecular kinetic energy
when b is not 1, unproportional
Allometric equation
M=aW
b equal to 1, proportional relation
Rubner’s Surface area law (1883)
based on the surface area to volume ratio, which grows as 2/3 in a geometrically scaling system.
developed for animals, release heat through their body surface, but doesn’t explain the allometry for other poikilothermic animals.
Rubner’s law
Branching circulatory systems must fill space optimally to service all cells. 3/4 exponent
fractal, space-filing transport theory
Specific Dynamic Action
feeding causes increase in metabolic rate
