Chapter 7: Cellular Respiration Flashcards
general formula for respiration
C6H12O6 + O2 -> CO2 + H2O
general formula for photosynthesis
CO2 + H2O -> C6H12O6 + O2
what do cells run on?
ATP
where does glycolysis occur?
cytoplasm
where does the Krebs cycle occur?
matrix of mitochondria
where does the transition step?
matrix
where does the ETC and ATPace occur?
cristae of mitochondria
anaerobic vs aerobic respiration
anaerobic- no O2
aerobic - O2
what are the steps for anaerobic respiration?
glycolysis, fermentation, reactions
what are the steps for aerobic respiration?
glycolysis, import into mitochondria,, Krebs cycle, electron transport
what is the main purpose of cellular respiration?
break down sugar to make ATP
what is the first stage of aerobic respiration?
glycolysis- happens in the cytoplasm
what is the 2nd step of the aerobic respiration?
import into the mitochondria (transition step) - occurs in the matrix
what is the 3rd step in aerobic respiration?
Krebs cycle (citric acid cycle) - occurs in the matrix because it needs to be in liquid
what is the 4th step of aerobic respiration?
electron transport chain and ATP synthesis- occurs in the cristae which is the folded inter membrane
how many molecules does glucose make?
2 pyruvate
what are the 2 parts of glycolysis?
part 1: energy investment
part 2: energy payoff
what steps and parts are in part 1 of glycolysis?
energy investment (steps 1-3)
cleavage and rearrangement (steps 4-5)
what is the step and part of part 2 of glycolysis?
energy payoff phase (step 6-10)
what is the energy investment formula of glycolysis?
Glucose (C6) + 2ATP -> Fructose (DHAP + G3P) -1-6bisphosphate (C6) + 2 ADP
what is the cleavage and rearrangement formula?
fructose 1-6bisphosphate (C6) -> 2G3P (C3)
G3P=glyceraldehyde-3-phosphate
what is the energy input for glycolysis?
2 ATP
what is the output of glycolysis?
4 ATP and 2 NADH
G
what happens / formula for glycolysis part 2
(G3P C3->->-> pyruvate C3) x2
what is the substrate and products for glycolysis part 1?
glucose (C6 sugar)
2 C3 sugars - DHAP, G3P
what is the substrate and products for glycolysis part 2?
2 G3P
2 pyruvates (c3 sugars)
what is the energy input for glycolysis part 1?
What is the energy output for glycolysis part 2?
What is the net energy yield?
2 ATP
2 NADH and 4 ATP
2 ATP AND 2 NADH
what is the formula/ steps for import into the mitochondria?
(pyruvate C3 + NAD+ + CoA -> acetyl CoA C2 + CO2 + NADH) x2
what is the net energy yield/glucose for import into the mitochondria?
2 NADH
what is acetyl CoA?
Acetyl from pyruvate attached to coenzyme 1
what enzyme is used in import into the mitochondria?
pyruvate dehydrogenase
how many times do you do the Krebs cycle?
2
what is the Krebs cycle formula
2 acetylCoA C2 + 2 oxaloacetate C4 -> 2 citric acid C6 + 2 CoA
what is the 1st reaction of the Krebs cycle?
AcetylCoA C2 + oxaloacetate C4 -> citric acid C6 + CoA
how are sugars rearranged in the first reaction of the Krebs cylcle?
decarboxylated
oxidized
what is decarboxylated?
co2 is released/ cut off
what is oxidized?
reduced, high energy compounds are made- NADH and FADH2
what is produced after each Krebs cycle?
3 NADH and 1 FADH and 1 ATP
how is atp made in the Krebs cycle?
substrate level phosphorylation
when is a redox reaction occurring in the Krebs cycle?
anytime NADH and FADH is made
what is substrate level phosphorylation?
method of making atp in an enzyme reaction
one group of p is transferred from one sugar to atp
what is made per glucose for the Krebs cycle?
6 NADH + 2FADH + 2 ATP - it starts with 2 aceytle
why does the Krebs cycle happen twice?
per glucose there is 2 pyruvate and 2 acetyl CoA
what is the energy outcome of the transition step per pyruvate?
1 NADH
what is the total net energy yield per glucose of aerobic respiration?
4 ATP + 10 NADH + 2 FADH
Can most enzymes use NADH and FADH?
no so it has to be turned into ATP
what is the purpose of electron transport chain and oxidative phosphorylation?
uses the energy in NADH and FADH to make ATP by oxidative phosphorylation=chemiosmosis
what is oxidative phosphorylation?
uses the H+ gradient to make ATP
What is the electron transport chain?
Makes a H+ gradient
what does a reduced compound become?
oxidized- loses e-s
what does a oxidized compound become?
reduced- Gains e-s
what are electron carriers arranged by?
redox potential in cristae
How are electrons passed?
down the energy gradient in small increments
where are H+ pumped?
crossed the membrane
do the proteins/complexes move much
no- they are too big
what would happen if the energy would be released all at once?
It would be uncontrolled and atp would not be made because most energy would be lost to heat
a complex can only donate an electron to a
Lower energy level
NADH - coenzyme Q
oxidoreductase
complex 1
succinate - coenzyme Q
oxidareductase
complex 2
Coenzyme Q - cytochrome c
oxidoreductase
complex 3
cytochrome c
oxidase
complex 4
what do mobile electron carriers do?
go back and forth
What are the types of mobile electron carriers?
coenzyme Q / Ubiquinone - lipid
cytochrome c - small protein
each complex has how many electron carriers?
more than one
where can Q move?
the lipid bilayer between 2 and 3
what happens to H+ as electrons are transported down the ETC?
They are transported across the cristae membranes into the intermembrane space at 3 places: Complex 1,3,4
What will the H+ gradient be used for?
energy for ATP synthesis
What is ATP synthase?
uses H+ gradient as a source of energy to make ATP
How many electron pumping steps does NADH go through?
3 - makes bigger gradient
how much ATP does 1 NADH make?
3
How many electron pumping steps does FADH go through?
2 - makes smaller gradient
how many ATP does FADH make?
2
What complex donates electrons to oxygen to make water?
4
When NADH donates electrons to the ETC what is the order of electron carriers?
complex 1- Q - 3- cytochrome c- 4 - oxygen
When FADH donates electrons to the ETC what is the order of electron carriers?
Complex 2- Q-3- cytochrome c-4-oxygen
what is ATP synthase?
an enzyme that makes ATP - looks like a doorknob
What causes electron transport to stop?
Lack of oxygen and poison
what happens if electron transport stops?
no carriers can pass on their electrons (will be stuck in their reduced form), no H gradient is made, no energy to make atp, step 4 can’t pass on electrons to oxygen, reaction can’t take place, will start accumulating NADH and FADH
What does arsenic stop?
Krebs cycle and inhibits part of glycolysis
What happens if the Krebs cycle doesn’t have o2?
all NAD+ will be in NADH form
cells will run out of NAD+ and FAD+
any reaction that needs NAD+ or FAD+ will stop
what will happen to glycolysis if there is no o2?
it will stop unless there is another set of reactions to make NAD+ (fermentation)
what is the final step of cellular respiration?
ETC and ATP synthase
Makes ATP using energy from H+ gradient
ATP synthase
What are the energy conversions of 1 molecule of NADH and FADH after atp synthase?
NADH= 3 ATP
FADH= 2 ATP
why do you make more ATP form NADH than from FADH?
electrons from NADH pass through 3 proton pumping steps. It creates a large H+ gradient so it has more energy
electrons from FADH only pass through 2 proton pumping steps. It makes a smaller gradient
What is the maximum net yield per glucose of aerobic respiration?
38 ATP
How many ATP is made from substrate level phosphorylation and oxidative phosphorylation?
4/38
34/38
enzyme reaction
substrate level phosphorylation or oxidative phosphorylation?
substrate
enzyme reaction
substrate level phosphorylation or oxidative phosphorylation?
substrate
what requires oxygen?
substrate level phosphorylation or oxidative phosphorylation?
oxidative phosphorylation
what is aerobic respirations net energy yield per glucose? (Don’t convert)
glycolysis- 2 atp and 2 NADH
import into mitochondria- 2 NADH
Krebs cycle- 2 atp and 6 NADH and 2 FADH
Total - 4 atp and 10 NADH and 2 FADH
(All of this atp was made through substrate level phosphorylation
what is aerobic respirations net energy yield per glucose? (Covert)
glycolysis- 2 atp and (2•3=6 atp)
import into mitochondria- (2•3=6 atp)
Krebs cycle- 2 atp and (6•3=18atp) and (2•2=4atp)
total- 4 atp, 30 atp, 4 atp= 38
how does it cost to move nadh into the mitochondria?
2 nadh= 1 atp
2 nadh made in the cytoplasm moves into mitochondria which makes the total with shipping
36 atp
where does everything start out in for glycolysis?
cytoplasm
If there is oxygen, where do you go after glycolysis?
the mitochondria and do aerobic respiration
after glycolysis, if there is no oxygen what happens and where?
fermentation in the cytoplasm
What are the steps for anaerobic respiration?
glycolysis and fermentation reactions
what does fermentation do?
convert NADH into nad+
where does alcohol fermentation take place?
plants, fungi, and some bacteria
How many NADH does alcohol fermentation use up?
2
Is atp or oxygen made in fermentation?
No
Where does lactic acid fermentation take place?
animals and some bacteria
How much Nadh is used up in lactic acid fermentation?
2
in animals, what does fermentation covert?
pyrvate into lactate
In plants and fungi, what does fermentation covert?
pyruvate into ethanol
what is anaerobic respiration net energy yield per glucose?
Glycolysis- 2 atp and 2 NADH
fermentation- uses up 2 NADH
Total 2 atp
why is nadh used up in anaerobic respiration?
it turns into nad+
in fermentation, what does converting nadh into nad+ do?
keeps glycolysis going
what does glycolysis make in fermentation?
2 atp and 2 nadh
what does fermentation make in anaerobic respiration?
2 nadh goes to 2 nad+
what does lactic acid ferment to?
Cheddar cheese, yogurt, soy sauce
what does co2 and ethanol ferment to?
wine and beer
what does co2 and propionic acid ferment to?
Swiss cheese
what does acetone and isopropanol ferment to?
nail polish remover, rubbing alcohol
what does acetic acid ferment to?
vinegar
what food molecules can break down?
carbs, fats -tri, proteins
what do carbs metabolize to?
starch, disaccharides, sugars
what do fats metabolize to?
glycerol and fatty acids
what do proteins metabolize to?
amino acids
Where do starch and disaccharides enter the cycle?
how does it happen?
beginning of glycolysis
cuts off a glucose one at a time and the the two sugars are cut in half
where does glycerol enter the cycle?
middle of glycolysis
what food digestion is part 1 and 2?
1) carbs - C6 sugars
2) fats - C3 sugars
What does glycerol covert into?
glyceraldehyde 3 phosphate
Where do fatty acids enter the cycle at?
1st step of citric acid cycle
what uses beta oxidation and what is it ?
fatty acids- fatty acids is 18 carbon chain and is broken into acetyle CoA C2. There are 9 of these c2 chains
With triglycerides, how many times for the Krebs cycle go?
27 times- 9 times per fatty acid and there are 3 of them
what uses deamination and what is it?
proteins/ amino acids- NH2 (amino group) is removed from AA
where do amino acids enter the cycle?
Either import into mitochondria or 1st step or middle of citric acid cycle
what steps happen for pyruvate- acetyle CoA- citric acid cycle
transition and first reaction of krebs
what is converted to sugars that can be broken down during respiration?
amino acid c skeletons
what is the reaction of import to mitochondria or transition?
pyruvate (C3) + CoA + NAD+ -> acetyl CoA (C2) + CO2 + NADH
what is the 1st reaction of Krebs cycle?
acetyle CoA (C2) + oxaloacetate (C4) -> citric acid (C6) + CoA
what is the reaction of fermentation in animals?
pyruvate (C3) + NADH -> lactic acid (C3) + NAD +
what is the reaction for fermentation in plants and fungi?
pyruvate (C3) -> acetaldehyde (C2) + CO2
acetaldehyde (C2) + NADH -> ethanol (C2) + NAD*
can cells switch respiration?
yes - muscle cells can switch to anaerobic if oxygen isn’t reached so they will switch to fermentation temporarily
