Expiration
(Passive) Inspiratory muscles and diaphragm relax
External intercostals relax
Ribs and sternum move in and down
Inspiration
(Active) Diaphragm and external intercostals contract
Ribs and sternum move up and out
Diaphragm contracts and moves down
Pathway of air
Nasal cavity/mouth, Pharynx, Larynx, Trachea, Bronchus, Lungs, Bronchioles, Alveoli
Hering-breuer reflex
A reflex of the lungs that prevents over-inflation
Frank-Starling mechanism
An increased amount of blood in the ventricle causes a stronger ventricular contraction to increase the amount of blood ejected
How does the ATP/PC system produce ATP?
Phosphocreatine is broken down into creatine and a phosphate which is then used to phosphorylate ADP into ATP
How many ATP’s is produced in the ATP/PC system?
Net 1 ATP/PC
Where does the ATP/PC system take place?
Cytosol/cytoplasm of mitochondria
How long does the ATP/Pc system last for?
0-10 seconds
What is the limiting factor of the ATP/PC system?
PC stores run out quickly
ATP/PC system equation
PC -> Creatine + Pi
ADP + Pi + energy -> ATP
Anaerobic glycolysis equation
Glucose -> 2 Pyruvate -> 2 Lactate
Also, 2 NAD+ -> 2 NADH in G->P then 2 NADH -> 2NAD+ in P->L these get reused
How many ATP’s does anaerobic glycolysis produce?
Net 2 ATP/ glucose
Where does anaerobic glycolysis take place?
Cytosol/cytoplasm of mitochondria
How long does the anaerobic system last?
10 seconds- 2 mins
Why does fatigue occur?
H+ ions are produced alongside lactate, which increases the acidity of the blood and causes enzymes to slow down reaction rate
What happens in the aerobic system?
Oxygen is used to break down carbs, fats and a small protein amount (glucose). Lots of ATP is produced, but very slowly, as it has 3 different stages
What is the first stage of the aerobic system and what happens in it?
Glycolysis, where glucose is broken down into 2 Pyruvate and then into 2 Acetyl Co-enzyme A which is then used in the Krebs cycle
