Bioenergetics Flashcards
Define Bioenergetics
The study of transforming energy in living organisms
What is metabolism
The sum of all chemical reactions in the body
What are the two types of metabolic reaction
Catabolic and anabolic
What is a catabolic reaction
The breakdown/ degradation of molecules, releasing energy
What is an anabolic reaction
The synthesis of new molecules, where energy is released to build new molecules
What are examples of catabolic pathways
Proteolysis, lipolysis, glycolysis, glycogenolysis
What are examples of anabolic pathways
Protein synthesis, lipogenesis, gluconeogenesis and glycogenesis
In what 3 ways are catabolic and anabolic pathways regulated
Substrate supply, hormonal control and allosteric control
How are pathways regulated by substrate supply
By food and other compounds
How are pathways regulated by hormonal control
Switch on or turn off pathways and alter enzyme activity
How are pathways regulated by allosteric control
Speed or slow enzyme activity
What fuels all metabolic reactions
ATP
How does ATP generate energy
By breaking high energy bonds to release 1-2 phosphate groups energy is generated
How do enzymes speed up reactions
They lower the activation energy by moving molecules into the correct position
What is the activation energy
The initial energy required for the reaction to take place/ move the reactants into the correct position
Do enzymes change shape after a reaction
No
What are the two explanations for enzyme interaction and specificity
Lock and key and Induced fit
What is the lock and key explanation
Binding site of enzyme is complementary shape to substrate(s)
What is the induced fit explanation of enzyme interaction
Contact between part of the binding site and the substrate induces a change in the shape of the active site to bind to the substrate
what is allosteric control dependent on and why
The energy status of the cell as enzymes needed to generate energy can be switched on and off by allosteric binding
What is allosteric inhibition
Inhibitor binds to allosteric site of enzyme which alters its shape so the substrate can no longer bind
What is allosteric activation
Activator binds to allosteric site of enzyme, changes shape of binding site so substrate can bind
What are allosteric effectors
Molecules that activate allosteric enzymes depending on the energy status of the cell
How many grams of ATP is stored in muscle tissue
40-50
How many seconds is the ATP in muscle tissue used up in
2-4
What 3 anaerobic processes resynthesise ATP
ATP, phsophocreatine (PCr), Glycolysis
What 4 aerobic processes resynthesise ATP
Glycolysis, carbohydrate oxidation, fat oxidation, protein breakdown
Describe the relationship between rate of energy production and storage for the methods of resynthesising ATP
Inverse relationships (faster rate of ATP production, less source available)
List the ATP energy sources from fastest resynthesis to slowest
ATP, PCr, Glycolysis, carbohydrate oxidation, fat oxidation, protein breakdown
