Download Honors Biology Notes:

Honors Biology Notes:
Unit 4 BioEnergy
Metabolism and Energy
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chemistry of life is organized into ________________________________________________________
– metabolism: collection of reactions that occur in organisms; facilitated by _____________________
– two general categories of reactions:
• ____________________: breakdown of macromolecules into monomers, releasing energy from
the broken bonds
• ____________________: building macromolecules from monomers, using energy to form bonds
ATP (_________________________________________) powers cellular work
– ATP loses one _____________________, producing ADP (adenosine _____________________), a
phosphate group, and free energy
– Any time bonds are broken; energy is _______________________
– Any time chemical bonds are made, energy is ____________
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Chemical elements essential to life are recycled in the cells by photosynthesis and cellular respiration
(_________________________________________________)
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________________________ is not recycled
Photosynthesis
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General
– plants and other autotrophs are ___________________________________
• _______________________: organisms that can make their own food rather than ingesting or
absorbing it
• ______________________________: organisms that use the energy of the sun to produce
carbohydrates from CO2 and H2O
• _______________________: organisms that are the ultimate source of organic compounds for
heterotrophic organisms
– ___________________________ must ingest or absorb energy from other organisms
The Action Spectrum for Photosynthesis
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Look for the following information in the webpage:
In 1883, Thomas Engelmann devised an experiment to learn __________________________________
__________________________________________________________in carrying out photosynthesis.
What organism was used? _______________________________________
The wavelengths that work best for photosynthesis are ______________________________________
Chloroplasts
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chloroplasts are the ______________________________________ in plants and other photoautotrophs
– all _________________________________ of a plant have chloroplasts
– _________________________ are the major sites of photosynthesis in most plants
• about _____________________ chloroplasts per square ____________________ of leaf surface
– green color comes from the __________________________________________
• chlorophyll _____________________________________________
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Source of Reactants
•chloroplasts are found in tissue in the interior of leaves called __________________________
•carbon dioxide enters leaf (and oxygen exits) by pores in the leaf called ______________________
•water is absorbed by the _________________ and moved through the plant by veins
Photosynthesis
•Overall (simplified) chemical equation MEMORIZE THIS
_______________________________________________________________________________
•Carbon ____________________________________________________________________________
Nova Photosynthesis Overview
•MEMORIZE the following diagram!
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2 Major Stages of Photosynthesis
•________________________________ or photochemical reaction
•the _______________________________ or the thermochemical reaction or dark reactions
Light Reactions General
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require the energy of the sun
– occurs in the ______________________________________________ of the chloroplasts
– rely on two clusters of pigments with different types of chlorophyll and other pigments
• ___________________________________________ (absorb different wavelengths of light)
Calvin Cycle General
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does not directly require __________________________________
– occur for only a ____________________________ after sunset, because the reactions quickly use
up the __________________________________________ produced in the light reactions
occurs in the __________________ of the chloroplast
3 “turns” of the Calvin Cycle are required to produce ________________________________________
Factors Affecting Photosynthesis
• Light intensity
– ordinary daily sunlight yields ____________________________________ of photosynthesis
CO2
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– more CO2 equals a higher rate _______________________________________
• 6x CO2 can yield ________________ of photosynthesis
– atmospheric CO2 has increased ___________ in last 200 years; not enough to cause great increase
in photosynthesis
– greenhouse effect- greater impact on ________________________________________ than rate of
photosynthesis
• H2O- if plant goes dry ____________________________, no CO2 taken in.
• Temperature
– primarily via ______________________________________- as temperature increases, rate goes up
(until proteins _______________)
– low temperatures (> freezing) influence both _______________________________ and
“____________________” of chloroplast membrane
– most plants have enzyme systems and membrane structure that are _________________________
to the temperature range they experience
Cellular Respiration
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Breakdown of _____________________ (or other organic fuel) to produce energy
Occurs in _________________________________________ (even those that photosynthesize)
– overall (simplified reaction) (MEMORIZE)
_________________________________________________________________________________
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MEMORIZE the following diagram!
3 phases
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________________________________________
________________________________________
___________________________________________________________________________________
Glycolysis
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Glycolysis: glucose, C6H12O6 is ______________________________
– occurs in the ______________________ of the cell
– products: 2 molecules of _______________________, C3H3O3 and 2 molecules of ___________
and 2 molecules of ______________________ (electron carrier)
Krebs Cycle
• Krebs Cycle: pyruvate is converted to __________________
– occurs in the ____________________________________________
– transfers electrons to ________________________________________
– produces: ____________________________________________
– _____________________ (oxygen requiring) process
Electron Transport chain
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Electron Transport chain and ______________________________________________
– occurs on the ___________________ of the mitochondria
– produces up to ________________________
– _____________________ process
a maximum of ___________ molecules ATP are produced per molecule of glucose during cellular
respiration
Fermentation
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occurs ___________________ of Krebs Cycle and Electron Transport chain when oxygen is not present
– ___________________________ : absence of oxygen
Two types
– _____________________________ fermentation
– _____________________________ fermentation
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MEMORIZE the following diagram!
Alcoholic Fermentation
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pyruvate from glycolysis is converted to _______________________________________________
– occurs in ________________ (a fungus) and some bacteria
– used to produce _______________________________________________________
Lactic Acid Fermentation
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pyruvate from glycolysis is converted into ______________________________________________
– occurs in some fungi, bacteria, and __________________________________________ that have
depleted stores of oxygen
– used to produce ____________________________________
– in humans, cells must switch from cellular respiration to lactic acid fermentation when no oxygen is
present
• causes ___________________________________ and pain
• lactic acid is gradually carried to ________________________ by blood, and broken down into
____________________ in the liver
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