thermodynamics (bio week 4)

passive transport

moves molecules with concentration gradient (high to low)

facilitated diffusion

protein help protein to get across membrane

active transport

uses protein and energy to move molecules against concentration gradient (low to high)

what determines net direction of chemical reaction

characteristics of chemical equilibrium (ratio of reactant and products)

reaction rates

how fast a reaction occurs

chemical equilibrium

the state a reversible action reaches when the forward and reverse reactions are happening at the same rate, so concentrations of reactants and products stop changing overall (equal fast movement)

le chatelier's principle

when equilibrium is perturbed, the system shifts in whatever direction partially counteracts the disturbance, settling into a new equilibrium

thermodynamics

how energy is transferred and transformed

what determines if a reaction is favorable

change in Gibbs free energy Gfinal minus Ginitial

Gibbs free energy

amount of energy available to do work

Negative change in G

favorable, exergonic

Positive change in G

unfavorable, endergonic

what factors determine change of g of a reaction

change in enthalpy (H) minus temperature times change in entropy (S)

enthalpy

total energy of system (exothermic vs endothermic)

negative H

release of heat (exothermic)

positive H

absorbs heat (endothermic)

entropy

amount of disorder (low vs high entropy)

low entropy

low disorder/less even spread

high entropy

high disorder/more even spread

positive S

low to high entropy

negative S

high to low entropy