R1
What is catabolism? What is anabolism? What is bioenergetics?
Breakdown of molecules (catastrophe- breaking stuff)
Making of molecules (eating)
Converting food into energy we can use
What are the 5 factors that affect enzymes?
Substrate concentration --> amount and availability
Modulator - stimulator or inhibitor
Cofactors (coenzymes) (NAD+, NADH, FAD+, FADH)
Temperature - around 37 degrees
pH - optimal around 8
Why do we not store ATP?
It is very heavy, cannot carry lots around.
We store 80-100 g of ATP, 1 Unit of ATP weighs 0.5 g
What are the main nutrients in exercise metabolism?
Carbohydrates (glucose, glycogen, muscle and liver)
Lipids (fatty acids, triglycerides)
Proteins (amino acids)
When the enzyme under complex control what are the 4 things?
1. Competitive Inhibition
2. Non Competitive Inhibition
3. Feedback Inhibition
4. Enzyme Affinity
What are the 2 factors that affect energy production?
1. Total Energy Demand
2. Rate of Demand
Total energy demand and rate of demand are coupled
What are does glycolysis, glycogenolysis, glucogenogenesis?
Glycolysis - breakdown of glucose to pyruvate
Glycogenolysis - breakdown of glycogen to glucose
Glucogenogenesis - form glucose from non glucose things - ie pro vs fat
What happens when an enzyme binds and breaks a molecule down? Does exercise make the body warmer or colder and does it make more or less enzyme activity?
What is the key and what is the lock?
Releases the energy that was holding the molecule together
Exercise = warmer body = more enzyme activity
Enzyme = 🔒 Substrate = 🔑
Lactate dehydrogenase, acid dissociates and releases H+ which leaves the salt (lactate)
What is the money analogy?
Oxidative (Bank)
Glycolysis (Wallet)
ATP PCr (Change)
What happens in the mitochondria? Both prior and after acetyl coa?
Everything prior to creating acetyl coa happens outside the mitochondria
Everything after we create acetyl coa happens inside the mitochondria
How much ATP come from the oxidation of 2 molecules of blood glucose?
2 ATP directly from glycolysis
4 NADH (2 glycolysis and 2 PDH)= 10 ATP
Krebs cycle (2 direct ATP, 6 NADH, 2 FADH2)= 20 ATP
32 x 2 = 64
What is the actual yield of both NADH and FADH?
2.5 ATP
1.5 ATP
What are some other names for the Krebs Cycle?
Tri carboxylic acid
Citric Acid Cycle
What is muscle glycogen? What is blood glucose?
Muscle glycogen
Primary source during higher intensity, supplies most of first hour of exercise
Blood glucose (from liver)
Primary source during low-intensity, Important during long-duration exercise
What are the 3 enzymes involved with NADH + H+? How do we end krebs cycle?
Isocitrate dehydrogenase
alpha ketoglutarate dehydrogenase
malate dehydrogenase
it combines with acetyl COA and oxaloacetate
How do we get 6 molecules of blood glucose?
each molecules nets 2 ATP
produces 4 but uses 2 (remember HK!) (Hexokinase)
6 x 2 = 12 ATP
What enzyme is involved with FADH2, AND ATP?
FADH2 --> SUCCINATE DEHYDROGENASE
ATP --> SUCCINYL COA SYNTHETASE
What are the stimulator and inhibitor for each pathway?
ATP PC System --> Stimulator (ADP) Inhibitor (ATP)
Glycolysis --> Stimulator (AMP, ADP, P, high pH) Inhibitor (ATP, CP, CITRATE, pH decreases)
Krebs Cycle --> Stimulator (ADP, CA+, NAD+) Inhibitor (ATP, PI)
ETC --> Stimulator (ADP, PI) Inhibitor (ATP)
What does 1 cycle produce in Krebs Cycle? How many direct ATP and how many indirect ATP if each glucose generates 2 turns?
1 cycle
3 NADH
1 FADH
1 ATP
6 NADH = 15 ATP (INDIRECT)
2 FADH2 = 3 ATP (INDIRECT)
2 DIRECT ATP --> SUCCINYL COA SYNTHETASE RXN
= 20 ATP
What is the energy investment phase and what is the energy generation phase?
Energy investment phase (Lose 2 ATP)
involves the investment of two ATP molecules and results in the formation of two molecules of glyceraldehyde phosphate.
Energy Generation phase (Gain 2 or 3 ATP if you use glycogen)
Energy is extracted from the molecule and stored in the form of NADH and ATP.
4 ATP produced
2 NADH produced (Go to ETC)
2 pyruvate or 2 lactate
Net Production
1 glucose → 2 pyruvate or 2 lactate
2 ADP → 2 ATP
2 NAD+ → 2 NADH
What happens in the cytochrome oxidase?
ETC is a series of oxidation-reduction reactions
NADH is oxidized to NAD+
FADH2 is oxidized to FAD
H+ are pumped across inner mitochondrial membrane into intermembrane space
Creates electrochemical gradient because H+ ions wants to re-enter
When 2 H+ flow back in cytochrome oxidase it transfers them to one O2 molecule
ATP synthase uses the electrochemical gradient making H2O
What are the rate limiting enzymes for each pathway?
ATP PC System --> creatine kinase
Glycolysis --> Phosphofructokinase
Krebs Cycle --> Isocitrate Dehydrogenase
ETC --> Cytochrome Oxidase
If glycogen is used then 1 extra ATP will be netted from ________? We will have _____ instead of 2.
glycolysis and 3
If glucoses is made from glycogen is used by glycolysis then 3 ATP are made? What reaction do we use?
Glycogen to glucose 1 phosphate glycogen phosphate