Bioenergetics & Metabolism - Lecture 30 Flashcards
Type 1 Energy System (oxidative)
Mainly using Oxidative system; slow rate of atp production to use over long period of time; more mitochondria.
Type 2b
Mainly glycolytic/ATP PCR system which hardly uses oxygen so hardly need mitochondria. Easily fatiguable because ATPase produces a crazy amount in the 10-15 seconds it has.
Key Differences of Energy Systems
Rate of ATP production; capacity
Does the energy systems go back to 0 after being used?
No; with glycolytic and oxidative systems they are used continuously, and either one is used based on the intensity and duration of exercise
Why do H+ ions release in ATP-PCR?
Hydrogen ions get released in response to low ATP and build up of lactate. Causes movement to be sustained.
Creatine Kinase
CrP is broken down into Cr+Pi and releases energy
What happens when CrP releases energy
ADP and Pi grab that energy to make ATP
What does CrP and ATP show?
They essentially work together, but one has to happen in order for the other to work.
How can ATP repackage Cr + Pi
In the absence of exercise ATP can transfer its energy to build CrP
Purpose of Glycolysis
To use substrates (glucose) and break them down into molecules to create ATP
Where does Glycolysis happen?
In the cytosol of the cell
Do you need Oxygen for Glycolysis
No need for oxygen as this can be done with or without it, but it would create different molecules.
Why is ATP being used in glycolysis?
It’s used to change the molecules; 2 are used.
Carbon molecules?
Initially starting with 1, 6-carbon molecule (glucose) and ending up with 2, 3-carbon molecule. (Pyruvate)
What is produced from Glycolysis
2 NADH, 2 H+ ions, and a net atp of 2+
What can pyruvate be used as later?
Can be either formed into Acetyl-CoA or Lactate in the presence or absence of O2 respectively.
Purpose of Oxidative System?
To use oxygen to break glucose into ATP
When is fat used as fuel?
When there is no exercise
When is carbohydrates used as fuel?
When exercise is at high intensity
How does using fats and carbs connect to RER (Respiration Exchange Ratio)
RER is Vco2/Vo2 and this connects to substrates as the measurement tells you which substrate is being used during exercise.
What RER tells you it’s carbs?
1.0
What RER tells you its fat?
0.7
Why does carbohydrates produce more CO2?
In glycolysis from pyruvate to acetyl-CoA, more CO2 is produced so the RER becomes high.
In the Mitochondria
Cellular Respiration takes place in the presence of O2.
Why does ETC make either 32 or 34 ATP
Depends on the pathway it takes
What is the pathway for 32 ATP?
Active transport; ATP uses NADH to bring it into the mitochondria which creates 32 ATP
What is the pathway for 34 ATP?
Passive transport; no ATP used to bring NADH into mitochondria therefore, we have 34.
Where does Krebs Cycle occur?
In the mitochondria; oxygen present.
What molecule is being broken down in the Krebs cycle?
2 pyruvate molecules
What is produced at the end?
6 NADH + H^+, 4 CO2, 2 FADH and 2 ATP
How many cycles of Krebs cycle are there?
2, one for each pyruvate.
Why do the H^+ ions move towards the top of the complexes?
To get ready to make ATP
How are the H^+ ions moved?
Through breaking down the NADH and FADH and using electrons to escort them through the complex.
How do the H^+ ions come back from the intermembrane space?
Through high to low concentration through the ATP Synapse which ultimately allows for ATP to be constructed
Electron Transport Chain
Process in which electrons move H^+ ions through the membrane to help with the process of ATP
