Introduction to Metabolism Flashcards
Metabolism
- Anabolic and catabolic reactions
- Totality of an organism’s chemical reactions
What is anabolism?
Build up or create molecules
What is catabolism?
Break down of molecules
What is kinetic energy?
Energy of movement
What is potential energy?
- Stored energy
- Available to do work
What is chemical energy?
- Potential energy available for release in a chemical reaction
1st Law of Thermodynamics
- Total amount of energy in the Universe is constant
- Energy cannot be created nor destroyed, but may be changed from one form to another
When Bonds are formed…
Energy is released to the environment (on the product side)
When Bonds Break…
Energy is absorbed by the breaking bonds (on the reactant side)
Exothermic Reaction
- Reactions where energy is released
- Leaves the products with less chemical potential energy compared to the reactants
- Heat tends to be released
What is △H in exothermic reactions?
- The change in potential energy is negative
- Heat, light or other energy is usually given off in this type of reaction
Exothermic Reaction Example
- Respiration
- Makes ATP at the expense of a small investment
What does △H stand for?
- Change in enthalpy
- Change in heat
What does H stand for?
Enthalpy
What does Ea stand for?
Activation energy
Endothermic Reactions
- Reactions where energy is absorbed
- Leaves the products with more chemical potential energy compared to the reactants
- Heat tends to be absorbed, leaves surroundings cool
What is the △H in endothermic reactions?
- △H is positive
- The energy of activation is large
Endothermic Reaction Example
- Photosynthesis is an endothermic process
What type of reaction (endothermic or exothermic) requires less energy?
- Exothermic reactions
- The overall amount of energy is always lower
What type of reaction (endothermic or exothermic) is more common?
- Exothermic reactions
- They are always considered “spontaneous”
- These reactions are more likely to occur without too much work
What is the most common type of energy to be released or absorbed in potential energy diagrams?
Heat
Factors that determine whether a chemical reaction will occur
- Energy
- Entropy
What is entropy?
- The measurement of disorder in a system
What is △S?
- Entropy
- Change in order