Module 1: Lecture 3 Flashcards
glycolysis is done in how many reactions?
10
what is NADH?
a carrier of electrons and of a hydrogen
the energy we got from splitting open and breaking up a glucose molecule is mostly where?
in NADH and/or pyruvate
what is the 6 carbon molecule, glucose, broken down to?
two, 3 carbon pyruvates
where does the energy used to covert ADP to ATP come from?
some energy from the broken chemical bonds of glucose
- most energy is with the pyruvate
what is McArdle disease?
absence of enzyme involved in the first step of glycogen to glucose conversion
- they will have an energy deficency
how is glucose stored?
as glycogen in the inclusions in the cytosol part of the cell
what cells in our body have more inclusions in the cytosol for glycogen storage?
liver and muscle cells
where does pyruvate go to after glycolysis?
the mitochondrial matrix
why do we want cristae for increasing surface area?
electron transport chain proteins need to go in there for production of ATP
(2) pyruvate is decarboxylated, and turned into? (3 –>2 carbon molecule)
Acetyl-CoA x 2
waste: CO2 x 2
(O2 is coming from glucose and C is coming from pyruvate)
what happens in the TCA cycle?
acetyl CoA is added to a 4C molecule using an enzyme to make a 6Carbon molecule (citrate/citric acid)
how many steps in the TCA?
8
how many NADH do we generate in the TCA cycle per glucose molecules?
6
why is it called the Krebs cycle?
Krebs was the scientist who discovered it
why is it called the citric acid cycle or the TCA?
Acetyl-CoA enters the cycle by combining with a molecule called oxaloacetate (4 carbon) to make a 6 carbon molecule which is then catalyzed by an enzyme to generate a molecule called citric. Citric has 3 carboxylic groups in it, which makes it a tricarboxylic acid (TCA)
how many NADH are produced in the TCA per one glucose molecule?
2
how many FADH2 do we make per TCA cycle? per glucose?
1 per TCA cycle
2 per glucose
how many ATP per TCA cycle?
1 per TCA cycle
2 per glucose
what are the hydrogen carrier molecules?
Nicotinamide Adenine Dinucleotide (NAD+) and
Flavine Adenine Dinucleotide (FAD)
–> NADH and FADH2 (once hydrogens are added to both)
on average, NADH produces how much ATP in the ETC?
2-3 ATP (2.5 avg)
the way ATP is made in glycolysis is which ATP production system?
substrate level phosphorylation
other than ADP + P –> ATP, what is another example of substrate level phosphorylation?
GTP –> GDP + P –> ADP + P –> ATP
ADP + GTP <–> ATP + GDP
how many net ATP are created per one glucose molecule in glycolysis and the TCA? (together)
4
after TCA is complete, where is all the energy?
in the NADH and FADH2 (in the hydrogen)
where does the ETC happen?
inter membrane space
after TCA, the series of electron carrier molecules are going to be where?
on the inner membrane of mitochondria
how is most ATP produced?
from the NADH and FADH2 in the ETC
as the electrons are passed through each complex, they are losing energy. where is this energy going and how is it being used?
it is going into the complexes to allow them to change shape.
what happens when the last complex has the electron?
it has no where to pass it to, so it holds it. then the second last complex has an electron and has no where to pass it, so it holds it. this continues to make a backlog.
what is the final electron acceptor in ETC? When the electron is accepted, what does the acceptor turn into?
oxygen. then turns into H2O
If we stop breathing, where does respiration stop?
pyruvate decarboxylation
what is the average ATP made in respiration per one glucose molecule?
32 ATP
how many ATP does FADH2 make on average?
1.5 ATP
how many complexes are in the ETC?
4
what is a complex in the ETC?
a complex of molecules (proteins or not) that work together to carry the high energy electrons and carry them along
which complex does not reach the entire inner mitochondrial membrane all the way through?
the second complex
why does the second complex not reach through the entire inner mitochondrial membrane?
because the oxidation of FADH2 to FAD at complex II releases less energy than the oxidation of NADH to NAD+ at complex I
once complex 1 turns NADH into NAD+, the H+ is transported through the complex to where?
the intermembrane space
can ions travel across the membrane by itself? why?
no. because they are charged and are polar (water loving). the plasma membrane and other membranes are made of phospholipids which is lipids. water and lipids cannot be mixed.
- ions cannot cross the membrane because the membrane is hydrophobic and ions are polar (water loving)
- they are trapped until a channel(complex one) lets them in and out
the high energy electron from the NADH in complex one goes where after complex one?
complex 3, then 4
where is the only place that FADH2 can give its electrons?
complex 2
why does FADH2 generate less ATP than NADH?
because it moves less hydrogen ions
what is ATP synthase?
a complex protein made up of multiple subunits and its job is to generate ATP.
how does ATP synthase generate ATP?
uses a gradient of hydrogen ions that are concentrated in the intermembrane space
how does hydrogen end up in the intermembrane space?
through the complexes 1, 3 and 4
what happens in ATP synthase for it to make chemical energy in the form of ATP?
a mechanical turning of the protein complex (rotates to turn ADP into ATP)
- mechanical energy will be put in the phosphate group
what is the process of ATP synthase generating ATP called?
Chemiosmosis
how many NADH in cellular respiration total? how many FADH2? How much ATP does each generate?
10 NADH (x 2.5 = 25 ATP)
2 FADH2 (x1.5 = 3 ATP)
if no oxygen is available, what happens to the pyruvate in glycolysis? (anaerobic)
pyruvate is converted into lactate with the use of hydrogen from NADH.
when we do not consume any glucose, how does our body produce energy?
uses fatty acids and proteins (only if necessary) instead but they enter at the Acetyl CoA step
