Metabolic Processes - Chapter 4 - Pop Quiz 2 Flashcards
What is the majority of energy that enters the biosphere
solar radiation
What is the overall cellular respiration equation
C6H12O6 + 6 O2 —>
6 CO2 + 6 H2O
what is cellular respiration
a process that uses oxygen to harvest energy from
carbohydrates by metabolizing them
What does aerobic cellular respiration occur in
most eukaryotes and some prokaryotes
what are obligate aerobes
an organism that cannot live without oxygen
What are the three overall goals of cellular respiration
- break the bonds between the 6 carbon atoms of glucose resulting in 6 CO2 molecules
- move hydrogen atom electrons from glucose to oxygen forming 6 water molecules
- to trap as much free energy released in the process as possible in the form of ATP
What are the 4 stages of cellular respiration
- Glycolysis
- Pyruvate oxidation
- The Krebs Cycle
- Electron transport chain and chemiosmosis
Where does glycolysis occur
occurs in the cytoplasm, only stage not occurring within the mitochondria
Where does pyruvate oxidation occur
In the mitochondrial matrix
how much energy is required to make ATP
approx 3000 KJ/Mole
In all of glycolysis, what net products are created
+2 ATP, +2 NADH, +2H+, 2 Pyruvate
What is another name for glycolysis 1
Activation Phase
Why is Glycolysis known as activation phase
it uses 2 ATP as activation energy since it is an exergonic reaction
What is substrate level phosphorylation
the formation of ATP by the direct transfer of a phosphate group from a substrate to an ADP
What is different about cellular respiration in prokaryotes than eukaryotes
they only have glycolysis as there are no mitochondria
what is the difference in effectiveness between Glycolysis and Aerobic Cellular respiration
Aerobic cellular respiration is 17x more effective than glycolysis
What are the other sources of energy in a eukaryotic cell
Lactic Acid Fermentation, Alcoholic Fermentation
What is happening in Lactic Acid Fermentation
Pyruvic Acid from glycolysis turns into lactic acid, no ATP directly produced, regenerates coenzyme that allows glycolysis to produce 2 ATP
Where is lactic acid usually produced
in the muscles is where lactic acid is produced (anaerobic) causing pain
What is happening in alcoholic fermentation
Pyruvic acid turns into alcohol and CO2, no ATP produced, also regenerates coenzyme that allows glycolysis to continue
The creation of ATP is what type of reaction
endergonic
The breakdown of ATP into ADP is what type of reaction
exergonic
Why is the mitochondria referred to as the powerhouse of the cell
It is the location of the citric acid cycle and electron transport generating most of the ATP used by the cell
What is anaerobic respiration
a process that uses a final inorganic oxidizing agent other than oxygen to produce energy
What is fermentation
A process that uses an organic compound as the final oxidizing agent to produce energy
Anaerobic and fermentation are what type of reaction
catabolic, energy yielding reactions
what are obligate anaerobes
an organism that cannot survive in the presence of oxygen
What is a facultative anaerobe
an organism that can live, with or without oxygen
Howmany enzyme catalyzed reactions are in all of glycolysis
Glycolysis as a whole is a 10-step catalyzed process
Other than being broken down, what is happening to glucose in glycolysis
Glucose is being oxidized
What are the steps to glycolysis 1
Glucose undergoes phosphorylation into glucose-6-phosphate which is then rearranged into Fructose-6-phosphate which is then phosphorylated into Fructose-1,6-bisphosphate which then lyses open into two Glyceraldehyde-3-phosphate
Every phosphorylation in glycolysis 1 has what happening
ATP turning into ADP
Explain what is happening to G3P in Glycolysis 2 step by step
G3P is oxidized by reducing 2NAD+ into 2NADH turning into 1,3-Bisphosphoglycerate (BPG) which then undergoes substrate level phosphorylation turning into 3-Phosphoglycerate (3PG) which then is rearranged into 2-Phosphoglycerate (2PG) which then has its electrons moved turning into phosphoenolpyruvate and water removed, PEP then also undergoes substrate level phosphorylation turning into pyruvate
What happens at every substrate level phosphorylation in Glycolysis 2
4 ATP are created (1 per G3P), an enzyme is transferring a phosphate from a high energy substrate molecule to ADP
What is the overall chemical equation for all of glycolysis
2ADP + 2Pi + Glucose —–>
2 Pyruvates + 2ATP +2NADH +2H+
Howmuch of the one glucose molecule’s energy, do the two pyruvate molecules produced have?
around 75%
What in the outer membrane of the mitochondria allow pyruvate molecules from glycolysis to pass through
Large pores allow for the diffusion
What are the three steps to pyruvate oxidation
- Decarboxylation Reaction (CO2 waste is removed)
- Redox reaction (2 pyruvate oxidized, 2NAD+ reduced into 2NADH + 2H+, remaining 4C becomes 2 acetic acid)
- 2 CoA are attached to the 2 acetic acids forming acetyl-CoA held together by unstable C-S bond
What is the overall chemical equation for pyruvate oxidation
2 Pyruvates + 2NAD+ = 2CoA ——> 2 Acetyl-CoA + 2NADH + 2H+ + 2CO2 waste
Why is Acetyl-CoA important
critical in energy metabolism, macromolecules broken down for energy are converted to acetyl-CoA, if ATP levels are low (acetyl-CoA goes to kreb’s cycle to produce ATP), if ATP levels are high (acetyl-CoA is channeled to synthesize lipids which is why we accumulate fats when more calories are consumed than we burn)
What catalyzes pyruvate oxidation
multi-enzyme complex
Once the pyruvate from glycolysis enters the matrix, what happens?
undergoes pyruvate oxidation to form Acetyl-CoA
What is FAD+
Flavin Adenine Dinucleotide
What is the reduced version of FAD+
FADH2
How many turns of the citric acid cycle does glucose create and why
Since glucose generates 2 pyruvate molecules, it performs the citric acid cycle twice
How many ATP are made in the electron transport chain via chemiosmosis
32 ATP
Per glucose, what are the coenzyme yields from Glycolysis to the end of Krebs Cycle
12 Reduced Coenzymes: 2NADH (glycolysis), 2NADH (pyruvate oxidation), 6NADH (Krebs, 3 per cycle), 2FADH2 (Krebs, 1 per cycle)
Where is most of the energy kept before the ETC (Electron transport Chain)
The coenzymes
Where does the Krebs Cycle start
At oxaloacetate
What happens after oxaloacetate in Krebs
The acetyl group of Acetyl-CoA is added to the oxaloacetate
What happens after the acetyl group in Acetyl-CoA gets added to oxaloacetate
A 6 Carbon citrate or citric acid is formed
Any ATP made until the end of Krebs is made by what reaction
Substrate level phosphorylation
Any ATP made in the ETC via chemiosmosis is made by what reaction
Oxidative level phosphorylation, THINK THE PROCESS ENDS WITH AN ELECTRONEGATIVE O2
Where does chemiosmosis take place?
The Cristae
In the ETC, how do high energy electrons move?
It is a coupled redox reaction and the electrons move to an increasingly electronegative oxidizing agent every time.
Where are the proteins that make the ETC found
On the cristae, Red Dots on the folds (REMEMBER BONUS ON POP QUIZ)
What is a beneficial characteristic of the Cristae
The folded membrane provides increased surface area
Howmany steps are in Krebs Cycle
8 Step cyclical process
What is also known as the Transition STEP
Pyruvate Oxidation
In krebs, howmany CO2 are removed per turn
2CO2 removed per turn meaning there are no carbons left after krebs
Overall, what are the reactants in Krebs Cycle in one spin
Oxaloacetate + Acetyl-CoA + 3NAD+ + ADP + Pi + FAD
What are the overall products of Krebs Cycle
CoA + ATP + 3NADH + 3H+ + FADH2 + 2CO2 + Oxaloacetate
Why is oxaloacetate known to be both a reactant and a product in Krebs Cycle
This indicates that the process is cyclic
