Metabolism Flashcards
what is metabolism?
the sum of all chemical reactions in the body/the making and breaking of all molecules
what is metabolic pathway?
begins with a specific molecule which is altered in a series of intermediate steps, each catalyzed by a specific enzyme resulting in a product
catabolic pathways
release energy by breaking down molecules
anabolic pathways other name?
biosynthetic pathways
anabolic pathways
consume energy to build complex molecules
what is the capacity to cause change?
energy
kinetic energy
energy of motion
thermal/heat energy
kinetic energy due to the random motion of atoms or molecules
light/solar energy
radiant energy of electromagnetic waves in the visible portion of electromagnetic spectrum
potential energy
stored energy that matter possesses as a result of its location or spatial arrangement
chemical energy
potential energy available in molecules for release in a chemical reaction
closed systems
systems that are unable to exchange energy or matter with their surroundings
open systems
systems that allow energy and matter to move between the system and the surroundings
first law of thermodynamics
energy of universe being constant
only changes into different forms
second law of thermodynamics
energy transfers increasing the entropy/disorder of the universe
what is the entropy in life and organisms? what are they called?
have low entropy as they are very organized
“islands of low entropy” in an increasingly random universe
spontaneous process
a process that occurs without the inapt of energy / energetically favorable
can be harnessed to perform work
exergonic reactions
proceed with a net release of free energy
a downhill reaction
-delta G
endergonic reactions
require free energy to drive a reaction and are not spontaneous
uphill reaction
+delta G
when a chemical system is an equilibrium, what can it not do?
cannot do work
a cell at metabolic equilibrium is dead
one of defining features of life is disequilibrium
ATP
adenosine triphosphate stores the potential energy to react with water and powers cellular work
what does ATP mediate?
coupling - using exergonic processes to drive endergonic ones
how does ATP work?
when a hydrolysis reaction breaks an inorganic phosphate group off from ATP.
why are the products ADP (adenosine diphosphate) and inorganic phosphate, more stable than ATP?
the 3 phosphate groups are negatively charged and repeal each other like a compressed spring
what type of reaction is ATP to ADP?
exergonic/spontaneous reaction
Can ADP be broken down?
AMP (adenosine monophosphate)
characteristic of ATP
weak bonds
unstable
more stored potetntial energy
ADP + Pi (inorganic phosphate group)
stronger bonds
more stable
less stored potential energy
what is ATP made up of?
3 negatively charged phosphate groups
adenine
ribose
what is required to break bonds?
energy
what is phosphorylated intermediate?
enzymes take the detaches inorganic phosphate and attach it to another molecule
atp’s exergonic energy is coupled to another endergonic reaction
when reaction is complete, the inorganic phosphate is released and can reattach to ADP forming ATP once again