Energy and equlibria Flashcards
What does the first law of thermodynamics state (law of conservation of energy)?
The total amount of energy in an isolated system does not change but the energy may transform from one type to another.
Which are the first law of thermodynamics implications?
-Energy has to keep entering;
-Energy available to do work decreases throughout food chain;
-Bioaccumulation happens;
-We can never create energy;
-No new energy is being created in the universe.
What does the second law of thermodynamics state?
The entropy of a system increases over time and the only way to avoid entropy is a continuous input of additional energy.
What is entropy?
Measure of the amount of disorder of a system.
Which are the second law of thermodynamics implications?
Entropy will always increase so organisms must continually put energy;
Increase in entropy is reduced by an input of food as a source of energy.
What is a feedback loop?
When information that starts a reaction in turn may input more information which may start another reaction.
Which are the two feedback loops?
Negative - promotes stability, reverses change and returns the system to the original state of equilibrium;
Positive - amplifies the change in the system and a small disturbance causes am increase in that disturbance.
What is a tipping point?
A part of a system that kick-starts self-perpetuating positive feedback loop that push the systems to a new state of equilibrium.
What is resistance?
System with self-regulating mechanisms that mantain the system in a steady state during a disturbance.
What is resilience?
Ability of the system to return to its original state after disturbance.
What is equilibrium?
When everything in a system is in balance.
Which are the two types of equilibrium?
Steady-state - open systems where there are continuous inputs of energy and matter but the system as a whole remains in a more or less constant state;
Static - when there is no change over time, if change happens a new equilibrium will be adpoted.
What are the two different stabilities of equilibrium?
Unstable equilibrium - system shifts to a new equilibrium after disturbance;
Stable equilibrium - systems returns to the original equilibrium after disturbance.
What is stability?
The ability of a system to remain in balance.
