Mock Exam - Moodle Flashcards
(46 cards)
A small molecule that decreases the activity of an enzyme by binding a site other than the catalytic site is termed
Allosteric inhibitor
Almost all of the oxygen one consumes in breathing is converted to
Water
Aside form maintaining the intergrity of its hereditary material, the most important general metabolic concern of a cell is
To maintain a constatant supply and concentration of ATP
Both water and glucose share an -OH that can serve as a substrate for a reaction with the terminal phosphate of ATP catalysed by hexokinase.
Glucose is however way more reactive as a substrate than water because…
The larger glucose molecule is better at binding to the enzyme - i induces a conformational change in hexokinase that brings active site amino acids into position for catalysis
Conversion of 1 mole of Acetyl CoA to 2 mole of CO2 and CoA during Krebs results in the net production of
1 mole of FADH2
1 mole of ATP or GTP
3 moles of NADH
Energy requiring metabolic pathways that yield complex molecules from simple precursors are
Anabolic
Enzymes are different from other catalysts because ONLY they…
Display specificy towards a singly reactant
The reaction L-Malate + NAD+ —> Oxaloacetate +NADH +H+
Free gibs = +29.7kj.mol. Is it possible
Can occur in cells at certain concertations of substrate and product .
This is because of:
1. product removal shifting equilibrium
2. Coupling with exogernic reactions as driving force
Glycogen is converted to monosaccharide units by
Glycogen phosphylase
Glycogenin is
The primer that new glycogen chains are initiated
Glycolysis is the name given to a metabolic pathway occurring in many different cell types. It is an example of
An ATP producing pathway
How is trypsinogen converted to trypsin
Proteolysis ( breakdown of protiens into smaller peptidesor amino acids by hydorlysis of peptid bonds) of trypsinogen forms trypsin
If free energy change, delta G, for a reaction is - 46.11kj/mol, the reaction is
Exogernic
Ketone bodies are formed in the liver and transported to the extrahepatic tissues mainly as…
Beta-hydroxybutryic acid
It also becomes acetoacetate
An enzyme involved in glycolysis, aldolase, requires Zn2+ for catalysis. Under conditions of zinc deficiency, it would be referred to as the
Apoenzyme
Anaerobic conditions of 1mol of glucose to 2mol of lactate by fermentation is accompanied by the net gain of
2 mol of ATP
The conversion of fructose 1,6 - bisphosphate to 2mol fo pyruvate by the glycolysis pathway results in the net production of
2mol of NADH
4 mol of ATP
Conversion of palmitoyl-CoA to myristoyl-CoA and 1mol of acetyl-CoA by beta oxidation pathway results in the next production of
(1 cycle )
1 mol of FADH2
1mol of NADH
4mol of ATP
1 acetyl-CoA molecule
The free energy, delta G, of ATP hydrolysis to ADP+ Pi in the cell is usually
-50kj/mol - 70kj/mol
The lineweaver - Burke plot is used to
Solve, graphically, for the rate for an enzymatic reaction at infinite substrate concentration
The number of substrate molecules converted to products in a given unit of time by a single enzyme molecule at saturation is referred to as…
Turnover number
If a reaction has a delta G of -20kj/mol at 25 degrees celcius, what will happen regarding the reactants and products at equilibrium
The products will move forward and produce more of this as this is the favorable direction
If delta G was positive then the reaction would move backwards creating more reactants
What is the role of an enzyme in an enzyme catalysed reaction
To increase the rate at which substrate is converted into product
