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Cellular respiration
QUIZ
Question | Answer |
---|---|
Cellular respiration formula | 6 (O2) + C6H12O6 → 6 (CO2) + 6 (H2O) + Energy |
3 processes of cellular respiration | Glycolysis, Krebs cycle, Electron transport chain |
Where does glycolysis occur? | In Cytosol of cell |
where does Krebs occur? | In mitochondrial matrix |
where does ETC occur? | inner membrane of mitochondrion |
During cellular respiration hydrogen is transferred from to what? | glucose to oxygen |
During the transfer of glucose to oxygen, what is formed? | water |
redox reactions | Rxns that transfer electrons from one substance to another |
reduction | the gaining of electrons during redox reaction |
why does gaining electrons cause something to be reduced? | adding electrons is called reduction because negatively charged electrons added to an atom reduce the charge of that atom. |
LEO the lion says GER | loss of electrons is oxidation, gain of electrons is reduction |
In cellular respiration what becomes oxidized? reduced? | glucose is oxidized, oxygen is reduced |
Glycolysis products | 2 molecules of pyruvic acid 2 molecules of ATP 2 moleules of NADH (4-2) |
1 step of glycolysis | 1 molecule of glucose is broken in half , the two halves convert into pyruvic acid. |
Where does the pyruvic acid go? | to the krebs cycle |
How many ATP are used and made? | 2 used, 4 made= net gain of 2 |
What happens to the high energy electrons in glucose? | they are transferred to NAD+ and convert into NADH and then drops its electrons off at the ETC |
How fast are ATP's produced? | 1000's inn a few milliseconds |
Does gylcolysis need O2? | no, but Krebs and ETC do. This means NADH cant pass electrons to the krebs and ETC. |
when does glycolysis stop? | when NAD+ are full |
If ATP is still needed, how is NAD+ regenerated? | Fermentation converts NADH to NAD+ by passing high energy electrons back pyruvic acid. |
does fermentation need O2? | no |
Types of fermentation | lactic acid and alcoholic |
Lactic acid | Pyruvic acid + NADH → lactic acid + NAD+ |
Alcoholic | Pyruvic acid + NADH → alcohol + CO2 + NAD+ |
Yeast | creates alcoholic beverages and bread, CO2 is the air bubbles |
Does the krebs cycle or ETC need O2? | yes, they are aerobic |
Who is Hans Krebs? | a british scientist that proved the krebs cycle in 1937 |
What is another name for the Krebs cycle and why? | Citric acid cycle because citric acid is the first compound formed in the cycle |
first step | pyruvic acid is broken down into CO2 in a series of energy exrtracting reaction |
What happens to the pyruvic acid once it enters the mitochondrion? | It is converted to acetic acid and in the process a carbon atom is given off as a molecule of CO2 |
What does acetic acid need to do before entering the krebs cycle? | it must join with the coenzyme called Acetyl CoA. It is an enzyme derived from the b vitamin pantothenic acid |
What is CoA's job? | to escort Acetic acid into the krebs cycle. |
Once Acetyl CoA (2-carbons) enters the cycle what does it do? | it immediatly combines with a 4- carbon acceptor molecule called oxaloacetic acid, to become citric acid (6-carbons). |
What is released when Acetyl CoA enters the cycle? | Coenzyme A is released and goes to pick up another Acetic Acid. |
As citric acid moves thru the krebs cycle...? | 2 CO2 are given off (mouth), ADP turns into ATP, NAD+ turns into NADH, and FAD turns into FADH2 |
FADH2 | (nadh + fadh2) = high energy electrons are passed to electron carriers, if O2 is present, these elctrons will be taken to the ETC to convert ADP to ATP |
where does ETC get the high energy electrons from? | from NADH and FADH2 in glycolysis and krebs cycle |
what is the ETC? | a series of carrier proteins located in the inner membrane of the mitochondrion. electrons are passed from one chain to the next, and at the end an 02 serves as a final acceptor |
What does the combination of O2, electrons, and H+ in an enzyme create? | water |
Is ETC aerbic or anerobic | aerobic, needs O2 |
what happens as the electrons move through the ETC? | hydrogen ions are moved across the inner mitochondrial membrane into the intermembrane space. |
what does the increase in hydrogen ions create? | a concentration gradient |
the hydrogen ions ddiffuse back across the membrane into the matrix thru what protein channel? | ATP synthase |
what happens as H+ moves thru the channel? | phosphate are attached to ADP creating ATP |
Totals (one glucose) | glycolysis=2 ATP + krebs cycle=2 ATP + ETC=34 ATP = 38ATP |
efficiency | 38% energy in one glucose and the other 62% is released as heat |