Biology 8-10 Flashcards
What is Free Energy?
Energy available to do work
Formula for free energy?
deltaG=deltaH-TdeltaS
What are the Laws of Thermodynamics
- Energy cannot be created or destroyed
2. Disorder is always increasing (entropy)
What are the properties of enzymes?
- Highly specific for their substrates
- Bind substrates in their active site
- Reusable because its not changed
- End in -ase
- Change activation energy
Activation Energy?
Energy required to break bonds
Active Site and Substrate Bonding:
substrates enter the active site where enzyme changes shape. substrates are held to enzyme by weak bonds. Enzyme works reaction faster by providing stable environment then substrates are converted to products and released. Enzyme is now ready for more
.
What are catabolic pathways?
pathway that releases energy by breaking down complex molecules to simpler compounds.
Ex. is respiration
What are anabolic pathways?
Consume energy to build complicated molecules from simpler ones.
Ex. synthesis of a protein from amino acids
Energy Coupling
the use of an exergonic process to drive an endergonic one. ATP powers this.
What are enzyme inhibitors?
Used to control the activity of a path way
What are the 2 main types of inhibitors?
Irreversible: use covalent bonds between inhibitor and protein
Reversible: use H bonds
What is a competitive Inhibitor?
Resembles structure of normal substrate to compete for active site.
(Cannot be overcome by adding substrate)
What is a Non-competitive inhibitor?
Binds allosteric site on enzyme and causes a shape change to reduce the ability of enzymes to bind substrate.
(Cannot be overcome by adding substrate)
What is Allosteric Regulation?
when an activator molecule binds to a site on the enzymes changing the shape and the functioning of its active site. This either inhibits or stimulates the active site.
What is Feedback Inhibition?
Metabolic control in which a pathway is switched off by the inhibiting binding of its end product to an enzyme used early on in the pathway.
Ex. is isoleucine
