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INTRODUCTION TO METABOLISM - Coggle Diagram
INTRODUCTION TO METABOLISM
thermodynamics
how energy is moved and transformed but not created
first law
energy use by living things
energy can be transferred and transformed but cannot be created or destroyed
also called the principle of conservation of energy
second law
every energy transfer increases the entropy of the universe
entropy is the measure of molecular disorder or randomness
spontaneous process
increase the entropy of the universe
occur without energy input
non spontaneous
decrease entropy
require energy inpuut
free energy and metabolism
totality of an organism's chemical eactions
metabolic pathway
a specific molecule is altered in a series of steps of produce a product
catabolic pathways
release enerrgy by breaking down complex molecules into simpler compounds
example is the breakdown of glucose in the presence of oxygen
anabolic pathways
consume energy to build complex molecules from simpler ones
example is the synthesisof protein from amino acids
bioenergy
the study of how energy flow through living organisms
forms of energy
energy is the capacity to cause change
kinetic energy
energy associated with motion
example water gushing through a dam turns turbines
thermal energy
energy associated with random movement of atom molecules
thermal energy in transfer of one object is called heat
potential energy
energy that matter possesses because of its location or structure
chemical energy is potential energy available for release in a chemical reaction
energy can be converted from one form to another
example, chemical energy chemical energy from food is used to perform work to climb up hills
free energy is the portion of energy that can do work when temp and pressure are uniform
exergonic reaction
net release of free energy to the surroundings
occurs spontaneously
energy coupling
the use of exergonic process to drive anb endergonic one
endergonic reaction
absorbs free energy from the the surroundings
non spontaneous
a cell does three main kinds of work
chemical work
pushing endergonic reactions
transport work
pumping substances across membranes against the direction of spontaneous movement
mechanical work
such as beating cilia or contracting muscle cells
the structure and hydrolysis of ATP
composed of ribose, adenine and three phosphate groups
energy is released when the terminal phosphate bond is broken by hydrolysis
the regeneration of phos
ATP hydrolysis causes a change in protein shape and binding ability
free energy, stability and equilirium
change G representsn the differenc e between free energy of final state and initial
if the reaction has negative, the system loses free energy and becomes more stable
equilibrium
the point at which forward and reverse reactions occur at the same time
reactions in a closed system like hydroelectric system eventually reach equilibrium and do no work
enzymes
macromolecules that speed up a specific reaction
catalyst
chemical agent that speeds up a reaction without being consumed by the reaction
activation energy
kinitial energy neede to break the bonds of the reactants
substrate
the reactant that enzyme acts on
most enzyme names end in -ase
example sucrase catalyzes sucrose into glucose and fructose
active site
region that binds the substrate
the rate can be sped up by increasing substrate concentration
cofactors
nonprotein helpers that bind to the enzyme permanently with the substrate
example metal atoms such as zinc, iron
enzyme inhibitor
many bind to the enzyme resulting to reversible inhibition
binds to the enzyme active site
competitivde inhibitors
noncompetitive inhibitor
bind to anothernpart of enzyme away from active site
examples toxins and poisons, pesticidess and antibiotics
regulation of enzyme activities
cells can regulate metabolic pathways by switching on or off that encode specific enzymes
allosteric regulation
when regujlatory molecule binds to protein at one site and affects the protein function at another site
may either inhibit or stimulate enzyme activity
most are made from polypeptide subunits
feedback inhibition
the end product of a ametabolic pathway shuts down the pathway
evolution of enzymes
are proteins encoded by genes
changes in genes lead to change in amino acid composition of the enzyme
alterred amino acids can result in novel enzyme activity