Ch. 9 Cellular Respiration Flashcards
big idea: glycolysis - prep step - CAC - ETC. following the energy of electron carriers (NAD+/FAD+) makes understanding this 10x easier. also understand fermentation
what is fermentation?
fermentation is the step cellular respiration takes if there is no oxygen, and forms ethanol [in bacteria/yeast] or lactic acid [humans]
what is aerobic respiration?
the process cellular respiration goes through when oxygen is present
what is the summary equation for cellular respiration?
C6H12O6 + 6O2 +ADP +Pi -> 6CO2 + 6H2O + ATP + heat
what is oxidation?
when a molecule in a rxn loses electrons or hydrogen = losing energy
often involves a gaining of O atoms
what is reduction?
when a molecule in a rxn gains electrons or hydrogen = gains energy
what is a reducing agent?
a molecule that causes the reduction of another molecule, getting oxidized itself
what is an oxidizing agent?
a molecule causing the oxidation of another molecule, getting reduced itself
what role do the coenzymes NAD+ and FAD+ play in cellular respiration?
the energy in electrons gets transferred from glucose to coenzymes, so NADH and FADH serve to carry the energy possessed by electrons [“high energy electron carriers”]
what are the coenzymes used in cellular respiration? what are they derived from?
NAD/NADH+ - derived from niacin
FAD/FADH2 - from riboflavin
TPP - from thiamine
Acetyl CoA - from pantothenate
what is the job of glycolysis?
to break down one glucose molecule into two pyruvate molecules for use in krebs cycle
what are the substrates of glycolysis?
-2 NAD+
-2 ADP + Pi
-1 glucose
what are the products of glycolysis?
-2 pyruvate
-2 ATP
-2 NADH
where does glycolysis occur?
in the cytosol of the cell
what is the prep step before the krebs cycle can begin?
-the 2 molecules of pyruvate created must be converted into 2x Acetyl CoA
where does the pyruvate “prep step” occur?
within the mitochondrion matrix
what are the substrates for the citric acid cycle? [4 of them]
-2x Acetyl CoA
-2x FAD
-6x NAD+
-2x ADP + Pi
what are the products of the citric acid cycle?
-4x CO2
-6x NADH
-2x FADH
-2x ATP
where does the krebs cycle occur?
within the matrix of the mitochondrion
what is the function of NADH and FADH in the electron transport chain?
to give their high energy electrons to proteins in the ETC to power the proton pump [creates gradient]
why is a proton gradient created in the electron transport chain?
-the gradient is established so H+ protons can flow back down the gradient through ATP synthase, which generates ATP from their kinetic energy
what is chemiosmosis?
an “energy coupling mechanism” that uses chemical gradient energy to do work
ex- ATP synthase
what happens to the high energy electrons once they have reached the end of the transport chain?
they are collected by a single O2 molecule (1/2O2), which picks up 2 H+ to balance the charges = creates water
where does the electron transport chain take place?
-within the matrix and intermembrane space of the mitochondria
what is the NET total of ATP generated from glycolysis, the krebs cycle, and electron transport chain?
-32 net ATP
-2 from glycolysis, 2 from CAC, 28 from ETC
what happens if a cell has no oxygen during the electron transport chain?
-electrons cannot get collected at the end of the chain
-ETC cannot occur
what is the purpose of fermentation in humans?
-to regenerate NAD+ from NADH to allow for glycolysis to continue
-to remove pyruvate by converting it to lactic acid so it can be removed as a waste product
