Energy and Metabolism Flashcards
Define kinetic energy
The energy possessed by moving objects
ex. raindrops falling, heart muscles contracting in heartbeat
Define potential energy
Stored energy- due to its position within an attractive or repulsive force field (ex. gravitational potential or chemical potential energy)
Define a catabolic reaction
The breakdown of complex substances
Define anabolic reactions
The build up of complex substances from simpler subunits
Define metabolism
The sum of all anabolic and catabolic processes (chemical reactions) in a cell or organism
Define the first law of thermodynamics
Principle that states the total amount of energy is in the universe is constant- energy cannot be created or destroyed but only converted from one form to another
- if an object has energy it does at the expense of loss of energy elsewhere
Define bond energy
The minimum energy required to break one mole of bonds between two types atoms
- equal to the amount of energy released when a bond forms
Is energy added or released when a bond is broken?
Added
Is energy added or released when a bond is created?
Released
Define activation energy
The amount of energy required to strain and break the reactants’ bonds
- to start a chemical reaction
What is activation energy equal to?
The difference between the potential energy level of the transition stage and the reactants
Define the transition state
Temporary condition in which the bonds within reactants are breaking and bonds between products are forming
Define an exothermic reaction
A chemical reaction in which energy is absorbed, giving the products more chemical potential energy than the reactants
- negative H value
Define an endothermic reaction
A chemical reaction in which energy is absorbed, giving the products more chemical potential energy than reactants
- positive H value
Define work
The ability to apply a force to move an object
- examples are breathing,
Define the second law of thermodynamics
In every energy transfer or conversion, some of the useful energy in the system becomes unstable and increases the entropy of the universe
Define entropy
The degree of disorder in a measurable quantity
Do all systems in the universe tend toward order or disorder?
Disorder
What causes an increase in entropy?
Any change, such as a chemical reaction
When does entropy increase in chemical reactions?
- solids react to form liquids or gasses
- liquids react to form gaseous products
- the total number of product molecules is greater than the total number of reactant molecules
Do living organisms defy the second law of thermodynamics?
No, energy can be expanded to establish and maintain order
- there is a greater increase in entropy in the universe than there is a decrease of entropy in the organism
Define a spontaneous change
A change that once started will proceed to completion without any input of energy
- ex lighting a match, burning paper, melting ice above 0
Are spontaneous changes catabolic or anabolic?
Catabolic
Define a non-spontaneous change
A change that once started, will not go to completion unless a constant supply of energy is input
- ex water melting at -10 degrees
