Chapter 6: How Cell Utilize Energy Flashcards
What is metabolism?
The totality of an organism’s chemical reactions.
What is Kinetic Energy?
The energy of motion.
The energy that is actually doing the work.
What is Potential Energy?
The energy that matter possesses as a result of its location or structure. (STORES ENERGY)
Heat or Thermal Energy
The kinetic energy is associated with the random movement of atoms or molecules.
Second Law of Thermodynamics
Energy cannot be changed from one form to another without the loss of usable energy.
Energy conversion increases the disorder of the universe.
Heat is the least usable form of energy.
Light Kinetic Energy
The type of kinetic energy that can be harnessed to power photosynthesis.
First Law of Thermodynamics
Energy in the universe is constant and energy can be changed from one form to another.
Energy cannot be created or destroyed!
Entropy
The measure of disorder, or randomness.
Chemical reactions will either…
Store energy or release it.
Endergonic Reaction
6 points to remember
Absorbs free energy from its surroundings and it’s not spontaneous.
* Increase in free energy
*High capacity to change
*Stable
*Stores Energy
*Non-spontaneous
*Anabolism
Exergonic Reaction
6 points to remember
Net release of free energy.
*Free Energy decreases.
*Low capacity to change
*Unstable
*Releases Energy
*Spontaneous
*Catabolism
Free Energy (G)
Amount of energy available to work.
Metabolic Pathway
SERIES OF CHEMICAL REACTIONS that either break down complex molecules or builds.
Catabolism
Breaks down complex molecules into smaller compounds.
(cellular respiration)
Anabolism
Builds a complex compound.
(photosynthesis)
What is ATP composed of?
Ribose (a sugar)
Adenine (a nitrogenous base)
Three phosphate groups.
Energy Coupling
USES THE ENERGY RELEASED FROM EXERGONIC REACTIONS TO DRIVE ESSENTIAL ENDERGONIC REACTIONS usually the energy in ATP molecules. One feeds into the other.
ATP is what kind of biomolecule?
Nucleic Acid.
Hydrolysis of ATP
ATP can be hydrolyzed to ADP by the addition of water. When one phosphate group is removed by breaking a bond, it releases energy.
Exergonic Process
Enzymes
Speed up the cell’s chemical reactions by lowering the energy barriers.
and also,
Start reactions
Stop reactions
Slow down reactions
Activation Energy (EA)
The required energy that is needed for the reaction.
If no enzyme is present..
Reactions will take longer to occur.
Substrate
Molecules that react with the enzyme.
Active Site
The specific design of the enzyme for specific molecules (substrate)
Enzyme-Substrate Complex
Enzyme and substrate are combined to create a reaction.
What two conditions can affect the activity of the enzymes?
Temperature and pH.
What is catalysis?
The reaction created when a substrate and an enzyme bind.
Cofactors
Nonprotein helpers.
Bind to the active site
Function in catalysis.
Involved in chemical process.
Inorganic compounds
Coenzyme
ORGANIC MOLECULES, such as most vitamins.
INVOLVED IN CHEMICAL PROCESS.
Inhibitor
A chemical that interferes with an enzyme’s activity.
Competitive Inhibitors
Block substrates from entering the active site and reduce an enzymes productivity.
Noncompetitive Inhibitors
Bind to the enzyme somewhere other than the active site.
Change the shape of the active site.
Prevent the substrate from binding.
PASSIVE
Allosteric Regulation of Enzymes
Either inhibit or stimulate an enzyme activity.
Occurs when a regulatory molecule binds to a protein at one site and affects the protein’s function at another site.
Prevents wasting energy
Maintains Homeostasis
Feedback Inhibition
Final product of the metabolic pathway can be used as a noncompetitive inhibitor for the first enzyme, which will shut down the metabolic pathway.
*prevents a cell from wasting chemical resources.
