Cellular Energetics

CELLULAR RESPIRATION AND PHOTOSYNTHESIS HAVE THEIR OWN FLASHCARDS

Kinetic Energy

Energy from movement

Heat Energy

Higher temperature means higher energy

Chemical Energy

Sort of potential energy

First Law of Thermodynamics

Conservation of energy- you cannot make or destroy energy, however you can transport it

Second Law of Thermodynamics

The entropy of the universe is always increasing

Delta G

Delta H - T Delta S

Delta S

Entropy

Delta H > 0

Endergonic- taking in energy

Delta H < 0

Exergonic- releasing energy

Reaction Coupling

The breaking of a phosphate from the triphosphate is an exergonic reaction and releases energy and becoms ADP

Enzymes

Macromolecules- biological catalysts that speed up biochemical reactions

Most enzymes

Proteins

Active Site

Interact with substrate

Enzyme Structure

Very specific and each enzyme only facilitating one type of reaction

All Biochemical Reactions

Require initial starting energy called activation energy

Change of Molecular Structure

May result in loss of enzyme function

Denaturation

Change in shape of enzyme- can be caused by change in pH and temperature

Optimum Temperature

Range in which enzyme mediated reactions occur the fastest

pH Measures

Concentration of hydrogen ions in solution

Optimum pH

Range in which reactions occur fastest

Competitive Inhibitors

Compete with normal substrate for the normal enzyme’s active site

Slowed Reactions

Inhibitor concentrations exceed substrate concentration

Irreversible Binding

Enzyme function is prevented

Noncompetitive Inhibitors

Enzymes have regions other than active site to which molecules can bind, called ALLOSTERIC site

Allosteric Site

Where noncompetitive inhibitors attach

Binding Causes

Conformational shape change

Binding Prevents

Enzyme function because active site is no longer available