Metabollic Processes Flashcards
What is energy
The ability to do work
What is metabolism
The sum of anabolic and catabolic processes in a cell or an organism
What is chemical energy
Energy stored in the bonds between atoms in molecules
What is potential energy
Stored energy
What is kinetic energy
The energy of motion
What is thermal energy
The energy of moving or vibrating particles resulting in heat
What is work
The transfer of energy from one body or place to another
What is the First Law of Thermodynamics
- the total amount of energy of the universe is constant. Energy cannot be created or destroyed but only converted from one form into another
- if an object or process gains an amount of energy, it does so at the expense of a loss in energy somewhere else in the universe
What is bond energy
- bond energy is the measure of the stability of a covalent bond. The minimum energy required to break one mole of bonds between two species of atoms
- the higher the bond energy the more stable the bond
What is the second law of thermodynamics
- the entropy of the universe increases with any change that occurs
What is entropy
- a measure of the randomness or disorder in a collection of objects or energy
When does entropy increase
- solids become liquids or gases
- liquids become gases
- complex molecules are broken down into simpler subunits (polymers into monomers)
- solutes move from an area of high concentration to an area of lower concentration until they are uniformly distributed in the given volume
What factors determine whether a chemical or physical change will occur spontaneously
Energy and entropy
When will a reaction most definitely proceed
If energy is released and randomness is achieved
What are the types of energy transfer
-substrate level phosphorylation (slp)
- oxidative phosphorylation (op)
- photophosphorylation (pp)
What is substrate level phosphorylation
ATP is formed directly in an enzyme-catalyzed reaction
What is oxidative phosphorylation
-mechanism forming ATP indirectly through a series of enzyme-catalyzed redox reactions involving oxygen as the final electron acceptor
- more complex than SLP and yields far more ATP molecules for each glucose molecule processed
What is photophosphorylation
-occurs only in chlorophyll containing plant cells or in certain bacteria that contain other light absorbing pigments
- complicated like OP
What is a coupled reaction
The energy released by an exothermic reaction can be used to drive an endothermic one
What does the process of cellular respiration convert
Energy into chemical energy stored in ATP molecules
What reaction is cellular respiration an example of
A coupled reaction
What is the process of cellular respiration steps
Simple molecules such as glucose, amino acids, glycerol, and fatty acids -> anabolic reactions transfer energy from ATP to complex molecules -> complex molecules such as glycogen, proteins, and triglycerides -> catabolic reactions transfer energy from complex molecules to ATP ->
What percentage of the energy released in catabolism is used for cellular functions
- 40%
- the rest is converted to heat, some for maintaining body temperature, the rest lost to the environment
What is ATP used for
-chemical work in synthesizing macromolecules
- mechanical work to permit muscles to contract, cilia and flagella to beat, chromosomes to move and others
- transport work to pump substances across the cell membrane
