Introduction to Metabolism Flashcards
What is catabolism?
The breakdown of molecules to release energy.
What is anabolism?
The synthesis of molecules to store energy?
What is the suffix of catabolic processes?
‘Lysis’
What is the suffix of anabolic processes?
‘Genesis’
Where does catabolism occur?
In the cytosol or mitochondria?
Where does anabolism occur?
Mostly in the cytosol.
What are the X4 stages of catabolism?
Which are aerobic and which are anaerobic?
Anaerobic =
1) Glycolysis
Aerobic =
2) Link reaction
3) Krebs/TCA/Citric acid cycle
4) Oxidative phosphorylation/Electron transport chain (ETC)
Glucose, fatty acids and amino acids all undergo different processes before entering the TCA cycle.
What pathway does glucose follow?
What molecule is produced at the end?
Glucose follows glycolysis.
It forms pyruvate.
Glucose, fatty acids and amino acids all undergo different processes before entering the TCA cycle.
What pathway do fatty acids follow?
What molecule is produced at the end?
Fatty acids follow the beta-oxidation pathway.
They produce acetyl CoA.
Glucose, fatty acids and amino acids all undergo different processes before entering the TCA cycle.
What pathway do amino acids follow?
What molecule is produced at the end?
Amino acids follow transamination.
They produce acetyl CoA.
What happens to pyruvate or acetate before entering the Krebs/TCA cycle?
1) Pyruvate is converted to acetate.
2) All acetate is converted to acetyl CoA in the link reaction so it can enter the TCA/Krebs cycle.
Where does beta-oxidation take place?
In the mitochondria.
Where does glycolysis occur?
What molecule from glycolysis enters the mitochondria for the link reaction?
The cytosol.
Pyruvate.
Where do the link reaction, TCA cycle and ETC occur?
In the mitochondria.
How are fatty acids transported in the blood?
Bound to albumin.
How do fatty acids enter the cytosol of a cell?
They break away from albumin (which they are bound to for transport in blood plasma) and enter via fatty acid membrane transport proteins.
Once in the cytosol, which molecules do fatty acids bind to which regulate their movement within the cell?
Fatty acid binding proteins.
What triggers glucose to be taken up by cells?
Insulin.
Which type of glucose transporters are responsible for insulin regulated uptake of glucose from the blood stream?
Where are these located and how do these work?
GLUT-4.
These translocate from vesicles inside the cell to fuse with the membrane and become expressed on the cells surface in order to become active.
Regarding the structure of ATP, what type of bond links the first phosphate molecule to the ribose sugar?
An Ester bond.
Therefore = a phosphoester bond.
Regarding the structure of ATP, what type of bond links the second phosphate molecule to the first, and also the third to the second?
Anhydride bondS.
Therefore = X2 phosphoanhydride bonds.
The cleaving of which bonds creates the energy from ATP breakdown?
What type of breakdown would break these bonds?
The X2 phosphoanhydride bonds.
Hydrolysis (the addition of water).
What is the structure of an ahydride group?
It is X2 acyl groups linked by a dehydration reaction to remove a molecule of water (as anhydride means formed by the removal of water). This leaves X2 acyl groups linked by a molecule of oxygen.
What is the amount of energy released when ATP —> ADP + Pi + energy?
30.5 kJ/mol.
