Lecture 5 Cellular Respiration Flashcards
3 Major Steps of Respiration
- Glycolysis
- Calvin Cycle
- Electron Transport Chain
Aside from glycolysis, Respiration occurs in the _____
Mitochondria
A coenzyme that drives cellular processes
NADH & NAD+
Nicotinamide adenine dinucleotide
NADH is ___ while NAD+ is ___ (Reduced/Oxidized)
NADH: Reduced
NAD+: Oxidized
Metabolic pathway that converts glucose into pyruvate and protons
Glycolysis
Accrual Formula of Glycolysis
Glucose - Glycolysis - 2 Pyruvate + 4 Hydrogen Atoms
2 stages/ phases of glycolysis are known as
- Preparatory (Preparing for ATP Produced)
- Payoff Phase
Which glycolysis stage/phase starts with E investment of 2 ATP (glucose)
& ends with splitting of 6-Carbon sugar into 2-Carbon molecules Glyceraldehyde 3-phosphate?
Preparatory stage
Which molecule signifies to the end of preparatory phase in glycolysis?
Glyceraldehyde 3-phosphate
Which glycolysis stage/ phase produces E yield of 4 ATP & 2 NADH, and results in 2 ATP & 2 Pyruvate?
Payoff phase
What is the glycolysis E net result of Prep & Payoff phase?
E net = 2 ATP & 2 NADH
Pyruvate is converted into ___
acetyl CoA
Glycolysis creates pyruvate in ___
Cytosol
2 Pyruvate enters the ___
Mitochondrial matrix
Glycolysis equation summarized
Glucose + 2NAD+ +2ADP + 2Pi →
2 Pyruvate + 2NADH + 2H+ + 2ATP + 2H2O
Which coenzyme is required to oxidize and decarboxylate both pyruvates?
Coenzyme A
What is a result of Acetyl CoA derived from glucose?
Carbon - useful in citric acid cycle
Original 2 pyruvate changed into 2 ___ groups
Acetyl
2 NADH is ___ from NAD+ (reduced/oxidized?)
Reduced
Which 8 enzymes are involved in Citric Acid Cycle?
- Citrate synthase
- Aconitase
- Isocitrate dehydrogenase
- a-Ketoglutarate dehydrogenase
- Succinyl CoA synthetase
- Succinate dehydrogenase
- Fumarase
- Malate dehydrogenase
There are a total # steps in the Citric Acid Cycle
8 Steps
Step 1 of Citric Acid Cycle + Enzyme involved
Acetyl CoA + 4-C compound (oxaloacetate) + H2O = 6-C compound Citrate
Enzyme: Citrate synthase (Putting things together)
Step 2 of Citric Acid Cycle + Enzyme involved
Addition of aconitase reconfigures citrate molecule
Enzyme: Aconitase
Step 3 of Citric Acid Cycle + Enzyme involved
Conversion of isocitrate to a-Ketoglutarate
CO2 molecule liberate, NAD+ reduced to NADH
Enzyme: isocitrate dehydrogenase
Step 4 of Citric Acid Cycle + Enzyme involved
a-ketoglutarate further reduced into succinyl CoA which releases CO2 & NADH
Enzyme: a-ketoglutarate dehydrogenase
Step 5 of Citric Acid Cycle + Enzyme involved
Creates ATP
Water release ATP & lyses CoA to form succinate
Maine closed circle occurs here (2 total)
Enzyme: Succinyl CoA synthetase
Step 6 of Citric Acid Cycle + Enzyme involved
Creation of FADH from FAD in reduction from succinate to fumarate
Gets kicked over to electron transport chain
Enzyme: Succinate dehydrogenase
Step 7 of Citric Acid Cycle + Enzyme involved
Requires water to alter fumarate into malate
Enzyme: Fumarase
Step 8 of Citric Acid Cycle + Enzyme involved
Malate changed to oxaloacetate with addition of malate dehydrogenase
NADH released
2nd closed circle
*Oxaloacetate regeneration
Enzyme: Malate dehydrogenase
What is Oxaloacetate regeneration?
The process in a cycle where the addition of water to molecule will begin whole thing all over again
Purpose of Electron Transport Chain (3 total)
-Build surplus of H+ in intermembrane space
-Creates concentration gradient
-Gradient used to power ATP production
Each transfer in the ETC ____ Energy
Each transfer LOSES E
What holds the e- carriers & enzymes required to catalyze the transfer from one carrier to the next?
An Embedded Complex
In the ETC, the e- move ____
Laterally
What are 3 Electron Carriers involved in the ETC?
Cytochromes (Cyt.), Iron-sulfur proteins (FMN), Coenzyme Q (CoQ)
Cytochromes
Carry 1 e- thru use of heme (Fe) groups
Iron-sulfur proteins (FMN)
Protein + sulphide pair
Coenzyme Q
Carry 1 or 2 e-
(ETC) Every time e- carrier accepts an e- it also picks up…
Also picks up H+ from mitochondrial matrix
When e-carrier gives its e- to next carrier, H+ is released into intermembrane space
There is more ___ve (+/-) charge on the outside than the inside
+ve
More +ve charge outside than inside creates a difference in electric charge called ___
Potential energy
Where does the +ve H+ travel through to get back into the matrix?
ATP synthase complex
ATP synthase uses the E of H+ moving down their gradient to produce ___
ATP
Anaerobic Pathway
ATP production without oxygen
Fermentation
Breakdown of glucose into ethanol without O2
Where does fermentation occur?
Cytosol
What does fermentation produce?
Produces ethanol (alcohol)
Pyruvate is converted ____ to alcohol in plants
anaerobically
2 steps of pyruvate anaerobic conversion
- CO2 is released (decarboxylated)
- NADH oxidized & acetaldehyde reduced
*Most E of glucose remains in alcohol
