L4 Energy and Metabolism Flashcards
What is the law of thermodynamics according to Boltzmann
Struggle for existence and struggle to possess free energy
What does ecosystem complexity depend on?
Number of species and interactions and forces from abiotic environment
What is mechanistic understanding of ecosystems?
The understanding of metabolism and the role it has on an individual and subsequently thr ecosystem
Define energy
Measureable property of an object that determines ability to do work
What is the purpose of using energy
Use energy to propagate yourself - autotrophs use photons, heterotrophs use chemicwl bonds
How does use of energy relate to ecology
There are different strategies for consumption/energy gain and fo investment
what does metabolic rate at cellular level dictate
life span, individual movement rate, individual development rate, maximum population growth rate
what is the relationship between between resting metabolic rate and body size
resting metabolic rate (B) increases with body size (M)
what is the power law equation for resting metabolic rate
B = B0M^b
why is the trend of body size and metabolic rate not exactly a straight line
it is staggered because we have ecto, endo and mesothermic organisms
in larger organisms, why is it that the energy is processed at a slower rate
to avoid overheating - heat dissipation - because volume is larger and therefore heat cannot be evacuated well
WBE model (fluid dynamics) - harder to distribute energy over a larger space
what is the relationship between metabolic rate and maximum population growth
it is inverse - larger organisms with slower metabolic rate have a lower rate of reaching maximum population growth
what is the equation for maximum population growth rate
rmax = r0M^-0.25
what ecological implication does larger body size have
population density is lower therefore species is rarer
why are carnivores “rarer” than herbivores of the same size
less energy availably higher in the food chain
what is another aspect of the organisms life that is impacted by body size
biomechanics and movement - gravity acts differently on different weights (Haldane)
how does climate affect organisms according to Darwin
affects their populations - there is a diference between species that live in constant or periodically changing climate
how exactly does temperature affect organisms/populations
chemical reactions are temperature dependent, higher temperature means higher kinetic energy (Boltzmann-Arrhenius equation)
what are the different thermal strategies and how are they chcracterized
- ectothermic - depend directly on external temp to regulate their system (most organisms)
- endotherms - regulate their own temperature by generating own heat
- mesotherm - “wobbly” thermostat, able to regulate to some extent (lamnid sharks, tuna, bill fish - minority of organisms)
what are the ecological implications of given thermal strategies
metabolic rate of majority of organisms depends on the outside environment
affected by climate change
population growth rate scales with temperature oúp to a certain point (Thermal Performance Curve)
