QUESTIONS AND ANSWERS WITH COMPLETE
SOLUTIONS VERIFIED
aA + bB --> cC + dD
A & B are reactants, C & D are the products, and a, b, c, & d are the number of moles of reactants and
products. This reaction is reversible, which means that A + B could be converted to C + D, or C + D could
be converted to A + B. The direction of the reaction depends on energy and on the concentrations of A,
B, C, and D. The two general factors governing the fate of a given chemical reaction in a living cell are its
direction and rate.
Energy
Capacity to do work or promote change; requirement of cell's growth, reproduction, and response to its
environment
Kinetic energy
Energy of motion
Potential energy
Energy substance possesses due to its structure or location.
Thermodynamics (heat changes)
Study of energy
, Feedback inhibition
regulation of simple biochemical pathways often involves the end-product binding to the allosteric site
of the first enzyme in the sequence
Biochemical pathways
series of sequential chemical reactions which are maintained in the cell
Metabolism
Total of all chemical reactions carried out by organism; includes all endergonic and exergonic reactions
ATP drives endergonic reactions
Cleavage of ATP's terminal energy bond releases more energy that other reaction consumes, two
reaction can be coupled
- under standard conditions, ATP can release 7.3 Kcal of energy for every molecule converted to ADP
How ATP stores energy
Phosphate groups are highly negatively charged à repelling each other (coiled spring)
Unstable bonds holding phosphate together have low activation energy (easily broken)
Breaking (catabolism) à transfer ▲ energy from chemical bonds or electrons to energy stored in ATP
ATP à ADP + Pi
ATP