Block B Flashcards
What is the first law of thermodynamics
Energy can neither be created nor destroyed (law of conservation of energy)
What is the second law of thermodynamics
The universe tends towards disorder (law of entropy)
What is entropy and what are the energy levels with high entropy vs low entropy
The degree of randomness in any system
High entropy = low energy level
Low entropy = high energy level
What increases the entropy and why
Heat because it increases the random motion of molecules
What is kinetic energy
Movement
What is potential energy
Stored energy
What is the enthalpy of a molecule
It’s energy content of heat content
What changes a molecules enthalpy
The conversion to a different structure during a chemical reaction, symbolised as ΔH
What is anabolism
Building molecules and consuming energy
What is catabolism
Breaking down molecules and releasing energy
What is hydrolysis
A chemical reaction where a water molecule is used to break a bond in a compound
What is phosphorylation
The attachment of a phosphate to a molecule
What is hydrogenation
A chemical reaction where hydrogen H4 is added to a compound
What are the 5 stages in an enzyme catalysed reaction
1 - substrates enter the active site
2 - substrates are help in the active site by weak interactions
3 - substrates are converted to products
4 - products are released
5 - active site is available for new substrates
What are the 2 mechanisms of enzymes
Lock and key - the shape of the active site is specific to the substrate and is a fixed shape
Induced fit - shape of the active site is flexible and changes shape to fit the substrate more snugly after binding
