Chapter 6a Flashcards
Metabolism
how energy flows through living systems
Bioenergetics
All of the chemical reactions that take place inside cells
Metabolism
A specific series of interconnected biochemical reactions that convert a substrate into a final product
metabolic pathway
building
anabolism
breaking down
catabolism
energy associated with objects in motion
kinetic energy
energy associated with the potential to do work
potential energy
type of potential energy that exists within chemical bonds and is released when those bonds are broken
chemical energy
a measurement used to quantify the amount of energy transferred when chemical bonds are broken and others are created during a reaction
free energy
Reactions that release free energy
exergonic
Reactions that require an input of free energy
endergonic
the study of energy and energy transfer in physical matter.
thermodynamics
the physical matter involved, and the environment it is in
energy system
the amount of randomness or disorder within a system
entropy
What is the conceptual difference between anabolic reactions and catabolic reactions? Which requires energy and which releases energy?
Anabolic is building and catabolic is breaking down
Anabolism requires energy and catabolism releases energy
Photosynthesis and cellular respiration are which types of reactions?
Photosynthesis is anabolic and cellular respiration is catabolic
What is the relationship between kinetic energy and potential energy? Given a scenario, be able to identify it as an example of kinetic or potential energy.
Kinetic energy is associated with objects in motion, potential energy is associated with the potential to do work
If released, potential energy could be transferred to kinetic energy
How is chemical energy related to potential energy?
Chemical energy is potential energy that exists within chemical bonds and is released when those bonds are broken
Be able to identify several common high-energy molecules used to transfer chemical energy:
-ATP (adenosine triphosphate)
-NADH (nicotinamide adenine dinucleotide
-NADPH (nicotinamide adenine dinucleotide phosphate)
Be able to apply the concept of free energy as it relates to exergonic and endergonic reactions.
Reactions that release free energy are exergonic
Reactions that require an input of free energy are endergonic
Understand how anabolic and catabolic processes relate to the concepts of endergonic and exergonic reactions.
Anabolic processes require endergonic reactions
Catabolic processes require exergonic reactions
Understand how the first and second laws of thermodynamics are applied to biological systems.
The laws of thermodynamics are laws of physics that govern the transfer of energy in an among all systems in the universe
Are biological systems open or closed systems? Why?
All are open system (energy can be transferred from the system to the surroundings)
What is the first law of thermodynamics?
First-energy cannot be created or destroyed
Energy is transferred from place to place/organism to organism
What is the second law of thermodynamics?
Second-none of the energy transfers are completely efficient
In every energy transfer, some of the energy is lost in a form that is usually heat energy
Much of the energy lost from every transfer of energy is lost in what form?
Heat energy
What is the main energy currency common to all living organisms? Why do cells need this energy currency?
ATP; is an energy supplying molecule that contains within some of its bonds, the potential for quick bursts of transferrable energy
What is the basic molecular structure of AMP? What 3 molecules is it composed of?
Adenine bound to a ribose and a single phosphate group
How does a molecule of AMP differ from ADP or ATP?
Amount of phosphate groups
Which of the bonds in the ATP molecule store the majority of transferable chemical energy?
The bonds that link the phosphates; the third to second are highest
What is a hydrolysis reaction?
Phosphate bonds are broken using a molecule of water
Know and understand the products and reactants of the hydrolysis reaction of ATP to ADP.
ATP+H2OADP+Pi+Free energy
What is phosphorylation? What is dephosphorylation?
Binding a phosphate group to a molecule
What is energy coupling? How is it applied in the case of the dephosphorylation of ATP?
Strategy where cells couple the exergonic reaction of ATP hydrolysis with endergonic reactions, allowing them to proceed
In human (and most animals) cells, a large percentage of ATP is spent powering what pump?
Sodium Potassium Pump
Why is the ATP molecule so unstable?
The phosphate groups are negatively charged and repel each other
Is the regeneration of ATP from ADP exergonic or endergonic?
Requires energy so it is endergonic
What is substrate-level phosphorylation? How is the sodium-potassium pump an example of this?
The energy from de-phosphorylation is used in the same reaction to phosphorylate a different molecule
~90% of ATP is regenerated from what type of process? Where does this process occur in eukaryotic cells? In prokaryotic cells?
Oxidative phosphorylation; mitochondria of eukaryotic cells; plasma membrane of prokaryotic cells
Oxidative phosphorylation relies on what transport process?
chemiosmosis
