Metabolic Processes (Unit 2) Flashcards
ability to do work
ENERGY
Living organisms must ______, _______ and _______ energy
capture, store and use
is produced by mitochondria in eukaryotes
ATP
the sum of the chemical reactions taking place—sums up anabolic and catabolic reactions
Metabolism
Type of energy that occurs as a result of motion
Kinetic Energy
Type of energy stored within an object; depends on location and/or chemical structure
Potential Energy
Two types of potential energy
Chemical potential
Gravitational potential
Chemical potential is caused by
(electrons and protons)
Gravitational potential is caused by
(distance from Earth)
“Energy cannot be created nor destroyed; it can only be changed from one form to another” is what law?
First Law of Thermodynamics
a.k.a. “Law of Energy Conservation”:
Energy conversion depends on
breaking and re-forming chemical bonds
Can electrons be attracted to multiple nuclei at the same time?
yes! = chemical bond!
Electrons have more potential energy the ________ they are from the nucleus
farther
For bonds to break, energy is _______ so it can be used to pull an electron away
absorbed
When new bonds are formed, energy is ________
released
A measure of the strength or stability of a covalent bond
Bond Energy
amount of energy released per mole when bonds form
Bond energy
Every reaction requires energy to begin the reaction, even if it ultimately produces energy true or false?
true
the energy required to begin a reaction
activation energy (Ea)
When bonds are broken, and new ones are ready to be formed, this is known as the
transition state
Endothermic rxn: net ________ of E
absorption
Ea = (give formula)
Epot (transition) – Epot (reactants)
Exothermic rxn: net _______ of E
release
“Every time energy is converted to another form, some of the useful energy becomes unusable and increases the entropy of the universe” what law?
Second Law of Thermodynamics
All systems in the universe tend towards _______
entropy
refers to the degree of disorder in a system
Entropy
Entropy increases when
product molecules > # reactant molecules
Living cells can create order by ________ energy
expending
Change that will continue to occur on its own once it has started
Spontaneous Changes
example of Spontaneous Changes
E.g. a match will continue to burn once it’s started; a diver will continue to fall once they have jumped
requires continual energy input
Non-spontaneous
Since rxns aren’t 100% efficient, whatever energy remains to do work is known as free energy (whats this called?)
Gibbs Free Energy
example of non-spontaneous changes
E.g. keeping a pot of water boiling
If ΔG is negative, energy is _________ (_________) 🡪 _______
released (exergonic) 🡪 spontaneous
If ΔG is positive, energy is _________ (_________) 🡪 _______
absorbed (endergonic) 🡪 non-spontaneous
_________ rxns release free energy, which can be used to make _________ rxns happen
Exergonic
endergonic
Rxns tend to be part of a
metabolic pathway
complex molecules broken down, releasing energy (e.g. cellular respiration) ΔG -ve
Catabolic
All living things perform activities that increase the _________ available
free energy
simple molecules combined, consuming energy (e.g. photosynthesis) ΔG +ve
Anabolic
ATP – (stands for)
Adenosine Triphosphate
a continual supply of energy is required for (4 things)
The energy comes from
Movement, growth, repair, reproduction
ATP!
Cells need energy to carry out many important functions such as:
-Mechanical work (beating cilia, muscle movement)
-Transport Work (pumping substances across membranes)
-Chemical Work (providing energy to build complex molecules)
ATP can be used to attach _________ to another molecule (phosphorylation) to supply it with ______
The _______ may make the molecule more reactive and more likely to undergo a spontaneous reaction
a phosphate group
ENERGY
phosphate
ATP consits of
-3 phosphate groups
-ribose sugar
-adenine
using energy released from one reaction to drive another reaction
Energy Coupling
ATP contains large amounts of _________ (energy that can do useful work)
FREE ENERGY
In ATP Specifically the crowded, __________ repel one another and weaken the bonds holding them together
These bonds can be ______ broken by ________ to release energy
-negatively charged phosphate groups
-easily
-by Hydrolysis
Cells must regenerate _______ in order to continue functioning (like recharging batteries)
ATP
Cells make ATP by combining ________ (Adenosine diphosphate) with a Phosphate group
ADP
ATP is generated through
the breakdown of more complex molecules in the food we eat (fats, carbohydrates, proteins)
The Universal Energy Currency
ATP
provides a manageable amount of energy for cell reactions (just the right amount)
ATP
ATP Can be assembled using the energy from a variety of different _____ molecules and can therefore be reliably utilized (no shortage of ATP)
food
Enzymes help chemical reactions
take place at ________ energy levels
LOWER
what allows your body to use less energy to drive reactions
Enzymes
enzymes DO or DO NOT supply energy for reactions
DO NOT supply energy for reactions
Help speed up the rate of reactions
Enzymes
Enzymes as Catalysts are Almost always ________
PROTEINS
the amount of energy required to start a reaction
Activation Energy
A __________ of energy is needed to help break the bonds of chemicals
certain amount
temporary state between
reactants and products (before new bonds are formed)
Transition State
Transition state occurs when __________ is required to begin reaction
enough energy
lower or higher activation energy when using a catalyst
lower
What Provides Activation Energy?
Thermal Energy
Catalyst (Enzymes)
Thermal Energy often causes more and more reactions to take place as more and more energy is ________
released
Lighting gasoline on fire
using a match is example of what
Thermal Energy
is thermal energy easy or hard to regulate
Hard to regulate
Allows reactions to occur using less energy
Catalyst (Enzymes)
Can be regulated to control rates of reaction
Catalyst (Enzymes)
In exothermic reactions do products have more or less energy then reactants
LESS energy
In endothermic reactions do products have more or less energy then reactants
MORE energy
How can Enzymes lower Activation Energy? (3)
- BRINGS REACTANTS TOGETHER
Orients molecules into position so they can bind
- CHARGED ENZYMES HELP BREAK BONDS
Charged functional groups help to attract reactants and break bonds
- ENZYME CHANGES SHAPE OF SUBSTRATE
Enzyme changes shape to change the shape of the
substrate and break bonds
What do gasoline and glucose have in common? (2)
Both have an abundance of Carbon-Hydrogen Bonds
These bonds hold a large amount of Potential Energy
The closer or farther away an electron is from the nucleus of an atom the MORE POTENTIAL ENERGY IT HAS?
farther
Energy is _________ as electrons move closer to the nucleus
released
Energy is ________ as electrons move farther away from the nucleus
absorbed
How is energy released?
As the electrons in the C-H bonds are pulled toward larger, more ________ nuclei
(from other atoms) energy is ______ and the electrons move to a ______ energy level
electronegative
released
lower
Oxygen atoms are very ________ and will pull the electrons closer towards their
nuclei. As they do so the electrons ______
electronegative
release energy
Reduction occurs when an atom or molecule _______ ELECTRONS from another
atom
GAINS
Oxidation occurs when an atom or molecule _______ ELECTRONS to another
atom
LOSES
As electrons are exchanged they may be shared in ___________ which
results in the ________
different arrangements
release of energy
