Metabolism (cellular respiration) Flashcards
Metabolism
the sum of all chemical reactions in a cell or organism e.g. digestion, production of molecules, etc.
Energy
Ability to do work, e.g. performed when energy is used to move an object against an opposing force (such as friction or gravity)
Anabolic reactions
building new chemicals
Catabolic reactions
break substances down
combination of these reactions in our cells is called?
metabolism
breaking a bond…?
requires and absorbs energy
forming a bond….?
releases energy
what do catalysts do
reduce the amount of activation energy to start a reaction ex. lower temp, and reaction and faster
What do chemical bonds do?
power work
What must occur for a reaction to occur or progress?
chemical bonds must be broken
All reactions require energy to begin (activation energy)
Kinetic energy
energy possessed by moving objects. e.g. thermal energy or heat, mechanical energy, electromagnetic energy, and electrical energy
Potential energy
Stored energy that an object possess as a result of its position relative to other objects or its internal structure. e.g. gravitational potential energy, chemical potential energy
1st law of thermo dynamics
law of conservation energy
energy cannot be created nor destroyed but converted from one form to another
- in most cases organisms obtain energy in one form and convert it t another form before it can be used. e.g. photosynthesis and food chains
Bond energy
a measure of the stability of a covalent bond
What happens when reactant products break
energy is absorbed
what happens when product bonds form
energy is released
What kind of systems are organisms (endergonic vs exergonic)
Endergonic- we need energy for various processes…
muscle contraction
active transport
synthesis- making polymers like protein or glycogen
movement
chemical reactions
temperature regulation
Endergonic reactions
if reaction absorbs more energy than it releases
- requires an input of energy
- all condensation reactions
Exergonic reactions
if reaction produces more energy than it absorbs
-overall release of energy
Energy coupling
we use exergonic (catabolic ) reactions to fuel endergonic (anabolic reactions)
Heat or enthalpy
overall change in energy
Which kind of reaction proceed spontaneously
Exothermic- products are more stable , less potential energy than reactants
What kind of reactions are non-spontaneous
Endothermic
Reaction is cooler than its surroundings
Endothermic