Chapter 6 Flashcards
Which enzyme helps the using up of stored ATP?
ATPase
Is energy produced when breaking down ATP to ADP? What is it used for?
Yes, used to power all forms of biologic work
In the presence of _____, phosphocreatine will create ATP.
ADP
Where did the ADP come from to help phosphocreatine?
From the breaking down of ATP. (1st equation)
Which enzyme helps PCr and ADP to form ATP?
creatine phosphate kinase
Which enzyme aids in the equation involving ADP + ADP?
Adenylate kinase
Which of the three equations is the one that makes energy used for biologic work?
1st equation of stored ATP
Which enzyme speeds up the reaction of glucose by charging it with a high energy phosphate bond and turning it into G6P?
Hexokinase
Where did the addition phosphase bond come from that charges the glucose?
It came from using stored ATP and breaking it down to ADP.
Glucose then changes form. What does it become and with which enzyme?
It becomes a fructose molecule (F6P), with the help of glucose-phosphate isomerase.
F6P is powered up again, how?
By ATP breaking down to ADP.
After F6P is powered up again, it forms what?
F 1,6 diphosphate.
Which enzyme speeds up the rate of reaction of F6P to F1,6diphosphate?
phosphofructrokinase
Why is PFK a rate limiting enzyme?
If you don’t have it maximally activated, then the process of glycolysis will stop there.
What will activate PFK?
ADP will activate it, so will phosphate, (so will ATP but its last resort).
F 1,6 diP breaks down to which 2 things?
Breaks down to 2 3-phosphoglyceraldehydes.
What happens to the 2 3-phosphoglyceraldehydes?
They both turn into pyruvate, then lactate.
What will get the excess hydrogens to use to take to pyruvate and then make lactic acid?
NAD+
As you move from pyruvate to lactate, the hydrogens from NADH + H+ will go to the lactate by which enzyme?
Lactate dehydrogenase
A low pH will ________ (increase/decrease) PFK activity.
Decrease
If you have decreased PFK activity, what does this cause?
Decrease glycolysis and decrease ATP production, which increases fatigue!
Explain how pyruvate becomes lactate by NAD+.
NAD+ breaks down to NADH + H, which allows pyruvate to add 2 hydrogens to it in order to become lactate.
What percentage of VO2 max in an untrained individual happens with increased lactate?
55%-60% VO2max.
Is NAD+ rate limiting?
YES