Download Lifeline Week 6 Follow-Along Sheet Cellular Respiration

Name _______________________
TA ____________________
Social Security Number_________ (Just kidding)
Lifeline Week 6 Follow-Along Sheet
Cellular Respiration
What is cellular respiration?
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The process of converting ______________ found in nutrients (the food we eat) into a form of
energy that can be used by cells for various cellular functions.
Key organelle = __________________
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Nutrients commonly used are sugars, amino acids, and lipids.
Cellular respiration is one of the main ways that cells obtain energy.
Involves a series of ________________ reactions.
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REDOX Review:
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Oxidation is the _____________ of an electron or the loss of an electron followed by a proton
(H+) from a compound.
Reduction is the _____________ of an electron or the gain of an electron followed by a proton
(H+) from a compound.
Cells use enzymes and REDOX reactions to transfer the energy found within large organic
molecules into a usable form of energy.
Adenosine Triphosphate (ATP):
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Usable energy is stored in the form of _____________.
ATP contains a sugar (____________), nitrogenous base (_____________) and
_______________________ groups.
ATP is a molecule that contains _______________________ bonds!
o These bonds are located between the phosphate groups shown below:
Mitochondria:
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ATP is produced within the mitochondrion.
Mitochondria are membrane-bound organelles found in eukaryotic cells and are found in both
animal and _______________ cells.
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Cristae –invaginations (folds) of the inner mitochondrial membrane.
o What is the purpose of the cristae?
§ To _______________________________________________.
Molecules involved in cellular respiration:
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ATP is the main energy source for the cell.
__________ and ____________ are coenzymes that are _______________ (have gained an
electron and a proton).
NAD+ and FADH are the _________________ form of the coenzymes (have lost an electron
and a proton).
These coenzymes are electron carriers that are required for cellular respiration to take
place.
What does the cell need to produce ATP?
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The breakdown of _______________ produces ATP.
o This process involves a series of steps.
glucose + oxygen -------> water + ___________ + ATP
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Exergonic reaction, as glucose is broken down into CO2 +H2O
REACTION TO KNOW!!!!
Memorize this: C6H12O6 + 6O2 -------> 6H2O + 6CO2 + **ATP**
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1 glucose molecule (6 carbon molecule) yields about _____ ATP.
3 Stages of Cellular Respiration:
1. _____________________
2. _____________________
3. ____________________________________________
Stage #1: Glycolysis
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Glycolysis means refers to the splitting of _______________.
o Takes place in the cytosol
o Occurs _________ or ______________ oxygen!
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1 glucose is broken down into _______________________.
A pyruvate is a _____ carbon molecule.
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Products of glycolysis = _______________________________________.
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Glycolysis does not release all of the electrons stored in glucose.
Most of the electrons are stored in the two pyruvate molecules.
So once glucose is broken down into the two pyruvate molecules, what happens next
depends on whether oxygen is present within the cell.
o Aerobic versus anaerobic state...
Assuming that oxygen is present...
Stage #2: The Krebs Cycle
• Prior to entering the Krebs cycle, each pyruvate molecule is converted to acetyl CoA (a ____
carbon molecule).
• Krebs cycle takes place within the _______________ of the mitochondria.
• Only occurs in the presence of ______________!
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The Krebs cycle produces molecules of ________, ___________, ____________, and ATP.
What is produced per PYRUVATE molecule?
• 1 ATP
• 4 NADH
• 1 FADH2
• 3 CO2
What is produced per GLUCOSE molecule?
• _____ ATP
• _____ NADH
• _____ FADH2
• _____ CO2
How many turns of the Krebs cycle does it take
to produce 2 ATP molecules? ______________
How many molecules of ATP have been
produced so far (glycolysis + Krebs cycle)?
______________
Why do we need NADH/FADH2?
• Remember: ___________ and FADH2 are coenzymes used as electron carriers.
• ______________________ are shuttled to the inner mitochondrial membrane where they donate
electrons to the “top” of the electron transport chain (the last stage of cellular respiration).
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In order to produce 36 ATP, all three stages of cellular respiration must occur!!
Stage #3: The Electron Transport Chain (ETC)
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The ________________________________ is a collection of molecules embedded in the
__________________________ of the mitochondrion.
Electron carriers (coenzymes) alternate between reduced and oxidized states as they accept
and donate electrons down the ETC.
o Example: NADH ------> NAD+ + 2e- + H+
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Electrons are transferred from NADH to the first molecule in the ETC.
o Electrons are passed down the ETC, molecule to molecule, until they combine with
oxygen and hydrogen ions to form water.
§ Energy is released during this process
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The ETC doesn’t directly make ATP!
Most of the energy extracted from glucose is in the form of _____________ and ____________.
Electrons travel down the ETC pulling H+ ions across the inner mitochondrial membrane,
creating a _________________.
o The proton gradient powers ATP synthesis!
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Finally, ATP is synthesized via ____________________________ driven by
________________________!
Note: Dr. Brooks discrepancy: ________________________________________________________
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2 Ways ATP can be formed:
1. __________________________________
o Generated by the _______________________
o Generates the most ATP... How?
o H+ ions leak back into the matrix via _____________________, a molecular complex
embedded in the mitochondrial membrane.
§ The energy derived from the movement of protons is harnessed to phosphorylate
____________ ------> _____________.
2. ________________________________
o Generated during ________________ and the _______________________.
o A small amount of ATP is produced from these processes.
o Pyruvate kinase is the enzyme that catalyzes substrate-level phosphorylation.
Questions:
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32 ATP molecules are produced by ______________________ __________________________.
How many ATP molecules are produced during glycolysis and the Krebs cycle?
o __________________________
o 2 ATP molecules produced from glycolysis
o 2 ATP molecules produced from the Krebs cycle
Total NET ATP: _________
Putting it all together...
The 1st stage of cellular respiration is _______________.
Takes place in the _______________ of the cell
During this step, one molecule of glucose is broken down into 2 _________________ molecules,
____ ATP, and _____ NADH are produced.
The 2 pyruvate molecules enter the 2nd stage of cellular respiration called the __________________
(when O2 is present).
Takes place in the __________________ of the mitochondria.
Both pyruvates are broken down and:
_____ ATP, ____ NADH, _____ FADH2, and ______ CO2 are produced (per glucose molecule).
The coenzymes NADH created during glycolysis and the additional NADH & FADH2 formed during
the Krebs cycle then transport _____________ to the ______________________________.
Within the ETC, electrons are passed along the _________ membrane of the mitochondria by transport
proteins. H+ ions move across the membrane, creating a __________________________.
This proton gradient creates a __________________________________ across the membrane.
This separation of charge is harnessed to do cellular work.
H+ ions leak back into the matrix of the mitochondria through a special protein channel/enzyme
called ______________________.
Within the electron transport chain, ATP is synthesized by ____________________________ via
_____________________________.
(________ ATP molecules are produced during this step.)
Additional notes:
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Fin. ;)