Chapter 8, Energy and Enzymes Flashcards
What is energy?
The system’s ability to do work. The capacity to cause change
What are the two major states of energy and explain the difference among them
Kinetic energy, is the active energy that is expended in the process of performing work (change)
Potentinal energy, is the stored energy that may peform work when converted into kinetic energy.
What are the 6 forms of energy
Radiant energy,
- Light waves (Visible, xray, gamma, infrared and radio), Solar energy
Thermal (heat) energy
-Energy from movement of atoms and molecules in a substance, heat increase with the movement of particles.
Chemical energy
- Energy storage in chemical bonds (potential energy) and reactions (kinetic)
Electrical Energy
- Delivered by electrons, movmement of electrons through a wire (kinetic)
Sound
- Longitudinal waves, produces when a force causes an object or substance to vibrate
Mechanical energy
- Object postion (potenial) is the tension or compression of mechanical energy
- Motion energy (kinetic) is the release of this potential energy in movement like wind.
What is metabolism?
Is the total (totality) of an organism’s chemical reactions
What do living organism need to live?
They need energy for metabolic reactions, they can not create energy, they must obtain energy from the enviorment (either photosynthesis or feeding)
What can be lost during metabolism
The transformation of energy during metabolsim can lead to loss of energy in the form of heat
What is a metabolic pathway, and what helps speed the process?
A metabolic pathway begins with a speicfic molecule and ends with a product
- Each step is catalyzed by a specific enzyme
What is an Catabolic pathway
A catabolic pathway releases energy by breaking down complex molecules into simipler compounds, with the objective of producing energy and building blocks for synthesis of new molecules (Cellular respiration)
Catabolic reactions are generally hydrolysis reactions
What is an Anabolic pathway
Anabolic pathway consumes energy to buidl complex molecules from similar to create energy storage or structural molecules (proteins). (Photosynthesis)
Anabolic reactiosn are generally dehydration synthesis reactions
What are 3 examples of work that a cell does?
Cell can produce, move, peform chemical reactions, grow and develop into specific shapes and structures
What is spontaneous
Occuring without apparent external cause
When delta G is negative, is it spontaneous or not?
Yes, spontaneous
When delta G is postive, is it spontaneous or not?
No, non-spontaneous
What does free energy in gibbons free energy equation measure?
It measures a systems’s instability, free energy decreases and the stability of a system increases.
What state gives maximum stability?
Equilibrium, a process is spontaneous and can perform work only when it is moving towardss equilibrium.
What happens to a cell if it reaches equilibrium?
The cell will die, as the cell is not performing any work. No longer changing energy or transfering energy/matter. Which prevents the cell from doing any future work and thus dies.
What is an exergonic reaction
An exergonic reaction proceeds with a NET RELEASE of free energy and is SPONTANEOUS. Examples are catabolic reactions or Hydrolysis. (Big thing -> small thing + release of energy)
What is an endergonic reaction?
An endergonic reaction ABSORBS free energy from its surroundings and is NOT SPONTANEOUS. An example is formation of proteins from amino acids or other anabolic reactions (small thing + absorbs energy -> big thing)
What is energetic copuling?
Is when free energy is released from one reaction is used to drive another.
List two ways that cells typically perform energetic coupling
Trransferring of phosplate groups (Phosphorylation)
Transfering electrons (redox rxns)
What reactions require energy from what reactions to synthesis more complex organic compounds?
Anabolic reactions require energy from catabolic reactions to synthesize more complex organic molecules.
What is the main energy of all cells that allows the cell to perform the work?
ATP, part of nucleotides family.
What is Phosphorylation?
Phosphorylation is the process of transfering phosphate groups, usually when ATP is hydrolyzed into ADP and P i + energy
Where is the available chemical energy stored in ATP? How does it get released?
The available chemical energy of ATP is held in the bonds connecting the phosphate groups, these phosphate groups are negative charged and tend to repel one another.
This repulsion aids when ATP reacts with water to release energy in an exergonic reaction releasing energy.
