Energy and Life
What are the two forms of energy
: actively doing work
: stored but not doing work
What is the first law of thermodynamics?
Closed system = no exchange of matter/energy with surroundings
Open systems = exchanged of matter/energy with surroundings
What is the first law of conservation of energy?
Energy cannot be crfeated or destroyed... but
Can be change in form
Means total energy does not change
What is the second law of thermodynamics?
Number of way this law can be expressed... including matematical
-No energy transaction can be completely efficient
-In closed systems, disorder (
) is increasing
Do living systems "obey" thermodynamics laws?
Energy create order
How is Earth is not a closed system?
received constant source of energy from the sun (solar power)
What is Metabolism?
Sum of all chemical reactions in an organism
What are the 2 types of metabolism reactions?
: reactions that build things
: Reactions that degrades things
How are reactions organized?
whole things makes a really complicated map...
How can chemical reaction be classified based on energy?
Reactions that release energy are
Reactions that absorb energy are
Metabolic can be either
Means exergonic reactionsa re spontaneous
Means endergonic reactions are not spontaneous
What is equilibrium
Most reaction are reversible, go in either direction
of forward =
Equilibrium in exergonic and endergonic
: equilibrium favors products
: equilibrium favors reactants
What does spontaneous mean?
But speed is variable
What are Enzymes?
Even exergonic reactions need activation energy
-energy to reach transitition state
How does enzymes speed up reaction?
Lower activation energy
-allows exergonic reactons to occur faster
-does not change amount of engergy released
How can enzymes be specific?
Bind to substrate:
What is ATP?
"portable" energy source... "energy currency"
-Synthesis of ATP is endergonic
-Hydrolysis of ATP is exergonic
How do we classify life base on carbon source?
: get carbon from CO
: get carbon from deit (consumers)
How are heterotrophs categorize?
Primary consumer eat producers (plants)
Secondary consumer eat primary consumers
...less nutrient the higher up the chain
is the lost of electron
is the gain of electrons
What are coupled
one atom/molecule is oxidized
one atom/molecule is reduced
In biological systems, electrons often go with protons
Oxidation is the loss of hydrogen (dehydrogenation)
Reduction is gain of hydrogen (hydrogenation)
Energy and Life
Animal Bio lecture notes 9/28, 9/30