Topic 3: Cell energy, metabolism and enzymes Flashcards
What is ATP?
Adenesine TriPhosphate
What is energy?
Ability to do work or be transferred as heat
1st Law of Thermodynamics?
Energy can not be created or destroyed. Energy is transferred and transformed
2nd Law of Thermodynamics?
Energy of systems tends to disperse. Entropy (disorder) is always increasing
What is metabolism?
Managing the materials and energy resources of the cell
-series of steps that create a pathway which requires enzymes
What is a catabolic Pathway?
Series of chemical reactions that involve the breakdown of complex molecules into simpler molecules
- releases energy
- ie hydrolysis of starch into glucose
What is an Anabolic Pathway?
Series of chemical reactions that build up complex molecules from simpler molecules
- requires energy
- ie dehydration synthesis of glucose to create starch
What is energy coupling?
Energy released from one set of reactions is used to power another set of reactions that require energy
What is G?
Free energy
-portion of a system’s energy that is available to perform work
Examples of systems with high free energy (G)
Molecules that are complex, large, and organized
- took energy to create
- Molecules are crowded
- Lower Entropy
- Unstable
Systems with low free energy (G)?
- Molecules simpler, smaller, disorganized, randomized
- not crowded
- high entropy
- more stable
How do you calculate delta G?
G products - G reactants
What does a negative delta G mean?
Energy left the system - reaction likely to occur spontaneously.
Exergonic
What does a positive delta G mean?
Energy entered the system (consumed)
Endergonic
Exergonic Reaction?
Releases free energy in the form of work and run to completion. delta G is negative
CATABOLIC
