AP BIOLOGY CELLULAR ENERGETICS
ENERGY EXCHANGES L AWS OF T HERMODYNAMICS First Law
PROBLEM
ANSWER
Cellular Energetics page 1
Second Law
ENERGY E XCHANGES
EXERGONIC REACTIONS
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ENDERGONIC REACTIONS
COUPLED REACTIONS
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ATP
STRUCTURE
PRODUCTION
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HOW ATP DOES WORK TYPE OF WORK
COUPLED REACTION
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DESCRIPTION
QUESTIONS : 1.
Define each of the following terms: Term
Definition
Metabolism
Catabolism
Anabolism
2.
3.
Identify each of the following as true of Catabolism or Anabolism. ______ Release energy
______ “Downhill” reaction
______ Store/consume energy
______ “Uphill” reaction
______ Build complex molecules
______ Photosynthesis
______ Break down complex molecules
______ Cellular respiration
Define the following terms: Term Energy
Kinetic Energy
Potential Energy
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Definition
4.
5.
Identify each of the follo wing as having kinetic energy (KE) or potential energy (PE). ______ Child at top of slide
______ Water turning turbines
______ Child sliding down slide
______ Glucose
______ Water behind dam
______ Food molecules
According to the First Law of Thermodynamics, if the total energy before a reaction is 500 kcal, then the total energy after the reaction must be: ________________________________________________________________
6.
According to the Second Law of Thermodynamics, if the total energy before an energy exchange is 500 kcal, then the amount of useful energy after the exchange is: a. b. c.
7.
Less than 500 kcal 500 kcal More than 500 kcal
Does the Second Law of Thermodynamics contradict the First Law? Explain. ________________________________________________________________ ________________________________________________________________ ________________________________________________________________ ________________________________________________________________
8.
Do highly ordered living organisms violate the Second Law of Thermodynamics? Explain. ________________________________________________________________ ________________________________________________________________ ________________________________________________________________ ________________________________________________________________
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In the equation ∆H = ∆G + T∆S, which part of the equation represents:
9.
10.
a.
Change in enthalpy?
_____________________________________
b.
Change in total energy?
_____________________________________
c.
Change in free energy?
_____________________________________
d.
Change in usable energy? _____________________________________
e.
Amount of energy available to do work? __________________________
f.
Change in entropy?
g.
Energy lost to the system? _____________________________________
_____________________________________
Complete the following chart: Graph A
Is ∆G positive or negative Exergonic or Endergonic Spontaneous Yes or No Uphill or Downhill Reaction Products have more or less energy than reactants
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Graph B
11.
Of the light energy reaching the earth from the sun, the earth’s plants are believed to convert less than 1% into the form of potential energy stored in the chemical bonds of food molecules. What happens to the rest of the energy? ________________________________________________________________ ________________________________________________________________
12.
Organisms cannot use heat energy to drive their energy-requiring processes. Does this mean that the heat released by metabolism is of no use to them? Why or why not? ________________________________________________________________ ________________________________________________________________ ________________________________________________________________
13.
Shown below is an energy pyramid for an ecosystem. Use this pyramid to answer the questions that follow.
Top Carnivore
Carnivores
Herbivores
Producers
a.
What happens to the amount of available energy at each trophic level? ___________________________________________________________
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b.
Use the laws of thermodynamics to explain why this happens. ___________________________________________________________ ___________________________________________________________ ___________________________________________________________
14.
What do the letters ATP represent? ________________________________________________________________
15.
What are the three main kinds of work performed by or in cells? ________________________________________________________________
16.
Identify the parts in the ATP molecule below.
17.
Diagram the chemical reactions that occur during the production and regeneration of ATP. Include the ∆G for the reactions.
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18.
Explain how ATP performs work. ________________________________________________________________ ________________________________________________________________ ________________________________________________________________ ________________________________________________________________
19.
When ATP is produced, energy is required. What is the source of this energy? ________________________________________________________________
20.
When ATP is broken, energy is released. How is this energy used? ________________________________________________________________
21.
What is the ∆G of a system (reaction) that is in equilibrium? ________________________________________________________________ Can a system at equilibrium do work? ________________________________________________________________ Explain why or why not. ________________________________________________________________ ________________________________________________________________ ________________________________________________________________
22.
How is equilibrium avoided in living systems? ________________________________________________________________ ________________________________________________________________ ________________________________________________________________
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