Membrane Dynamics Flashcards
Enzymes
Metabolism
The sum of all the chemical reactions that occurs within a living cell/tissue/organism
What is a metabolic pathway?
A series of steps beginning with a molecule (metabolite) with a different enzyme that catalyses each step
What is a catabolic pathway?
They release energy by breaking down complex molecules into simple compounds
What is an example of a catabolic pathway?
Cellular respiration (sugar broken down to CO2 and water in the presence of oxygen)
What are anabolic pathways?
They consue energy to build complex molecules from simpler compounds
What is an example of an anabolic pathway?
Amino acid synthesis
What are the advantages of multi-step pathways?
- Multiple points to control how fast the reactions occur
- Ability to divert ‘pathway intermediates’ to other pathways to do other things
- Changes to metabolism through evolution
All the pathways are interconnected by what?
Metabolic webs/grids
What are the forms of energy?
Kinetic energy
Thermal energy
Potential energy
Chemical energy
What is the 1st Law of Thermodynamics?
Energy cannot be created or destroyed, only converted or transformed
What is the 2nd Law of Thermodynamics?
Entropy increases in isolated systems
Increase in entropy can cause a process to proceed..
Spontaneously (doesn’t require energy) (does not mean instantaneously)
Are energy transformations 100% efficient?
No
Some energy is lost as heat
Do we need a continuous input of energy to keep order in the system?
Yes (ex. eating)
What is free energy?
The amount of energy in the system
Reactants have an initial free energy state
Products have a final free energy state