Energy Reactions In Cells Flashcards
Define metabolism
Set of processes that derive energy and raw materials from food and use them for repair, growth and activity of tissues of the body to sustain life
How are metabolic pathways seperated?
Some in all cells
Some restricted to some cells
Some restricted to compartments
What are catabolic pathways?
How are they related to energy?
Oxidative or reductive?
Break down larger molecules into smaller ones
Release free energy
Oxidative
What are anabolic pathways?
How are they related to energy?
Oxidative or reductive?
Synthesise large components from intermediary metabolites
Use energy from catabolism
Reductive
What is gibs free energy?
Useful energy
Key point about exergonic reactions
Only reactions that occur spontaneously
If ATP is NOT a carrier what is it?
Why?
A store
Limited amount of ADP
Why is ATP energy release controlled?
Stable in the absence of specific catalysts
What is AMP?
Has one phosphate group
Components of ATP
Three phosphate groups
Ribose sugar
Adenine
Why is AMP important?
Increases ATP production by glycolysis
Activates ATP dependent kinase that regulates gene expression
What is the enzyme that catalyses 2ADP > ATP + AMP
Adenylate kinase
What is creatine phosphate?
The main high-energy, phosphate-storage molecule of muscle
Give a reaction including creatine and ATP
Give the catalyst
Creatine + ATP > Creatine Phosphate + ADP
Creatine kinase - catalyst
How does a creatine phosphate work?
[ATP] high, leads to creatine phosphate formation
[ATP] low, leads to ATP formation
What does a cytosolic enzyme mean?
Appears in blood after cell damage
What is creatine kinase formed from?
Two subunits - M and B
Can be MM, BB or MB
How is creatinine produced?
Breakdown product of creatine and creatine phosphate
Spontaneous reaction at a constant rate
What does creatinine show (3)?
- kidney function (excreted via kidneys)
- excretion per 24hours is proportional to muscle mass - measure of muscle mass
- urine dilution
What type of food has the most energy?
Fats
What is energy measured in?
KiloJoules
Order carbohydrates, fats and proteins in the amount of energy
Fats
Carbohydrates
Proteins
What is the main form of energy in cells?
Chemical bonds
Where is creatine broken down?
Into what?
Kidneys
Creatinine
What stimulates more ATP production?
Give an example of a catabolic process to make ATP
When ATP conc decreases
2ADP>ATP+AMP (adenylate kinase)
Which phosphate group is hydrolysed in ATP?
Gamma phosphate (y)
Which molecule can be used to replenish ATP from ADP?
Phosphocreatine
