Chapter 5: Energy and Life Flashcards
1
Q
Energy
A
- The ability to do work
- Kinetic energy: motion
- Potential energy: stored energy
2
Q
Thermodynamics
A
- The study of energy or heat changes
3
Q
Chemical reactions
A
- Making and breaking of chemical bonds
4
Q
1st Law of Thermodynamics
A
- Energy cannot be created or destroyed
- Energy flows in one direction and some of that energy is dissipated as heat
5
Q
2nd Law of Thermodynamics
A
- Entropy: measure of the degree of disorder in a system
6
Q
Substrate (reactants)
A
- Starting molecules of a chemical reaction
7
Q
Products
A
- Molecules at the end of a reaction
8
Q
Endergonic reactions
A
- product contains more energy than reactants
- require input of energy
- not spontaneous
9
Q
Exergonic reactions
A
- produces products that contain less free energy than that produced by original reactants
- release energy
- can be spontaneous
10
Q
Activation energy
A
- initial input of energy needed to start reaction, break bonds
11
Q
Catalysis
A
- lowers the activation energy of a reaction
12
Q
Enzymes
A
- catalysts used by cells to perform particular reactions
- usually proteins but can be nucleic acids
13
Q
Induced fit model
A
- active site + reactant binding site = puzzle piece fit
14
Q
Biochemical pathway
A
- catalyzed reactions occur together in sequence
15
Q
Effect of temperature on enzymes
A
- as temp increases, reaction rate increases
- but, if temp gets too high, enzyme denatures and loses its shape and function
- optimal range for humans is 35-40° C
