Respiratory System Flashcards
What are myoglobin and haemoglobin ?
Proteins
Myoglobin stores O2 in the muscle then release it to mitochondria when needed
Haemoglobin binds to 4 O2 to make oxyhemoglobin and is in red blood cells
O2 in vascular system:
97% binds to haemoglobin
3% dissolve in plasma
Myoglobin has higher affinity to O2 than haemoglobin so takes O2 from it and stores it
O2 dissociates from haemoglobin at muscles due to low pressure of O2 there
CO2 in vascular system:
- 70% transported in blood as hydrogen carbonate ions
- CO2 waste from muscles diffuse into bloodstream it’s then taken by red blood cells and combined with water to create carbonic acid
- most carbonic acid dissociates to bicarbonate and hydrogen ions
- of the remaining 30%, 23% binds to haemoglobin and 7% dissolve in plasma
What’s the pathway of air ?
1.Nasal (nose) and oral (mouth) cavity
2. Pharynx
3. Larynx
4. Trachea
5. Bronchi
6. Bronchioles
7. Alveoli
What’s the structure of alveoli ?
Large surface area
Once cell thick
Moist walls
Surrounded by capillaries
What’s process of inhalation ?
- Diaphragm contacts and flattens
- External intercostals contract
- Pulling rib cage up and out
- Cause thoracic cavity size to increase
- Decreasing pressure in thoracic cavity
- O2 move from atmosphere (high pressure) to lungs (low pressure)
Additional muscles that help:
- sternocleidomastoid
- pectorals
- scalene
What’s the process of exhalation ?
- Diaphragm relax and goes back to some
- external intercostals relax
- pulling cribbage down and in
- cause thoracic cavity size to decrease
- increasing pressure in thoracic cavity
- gases move out of lungs (high pressure) to atmosphere (low pressure)
Additional muscles:
- internal intercostals
- abdominals
Definition of tidal volume
Amount of air inhaled and exhaled in normal breath
Define inspiration reserve volume
Max amount of air inhaled after normal inspiration
Define expiratory reserve volume
Max amount of air exhaled after normal exhalation
Define residual volume
Amount of air left in lungs after max exhalation
Define vital capacity
Total amount of air that can be exhaled after max inhalation.
Sum of tidal volume, inspiration and expiratory reserve volume
Define minute ventilation
Volume of air breathed in and out per min
define total lung capacity
Total volume of lungs after max inhalation including residual volume
Sum of vital capacity and residual volume
Respiratory control centre
Control depth rate and rhythm of breathing
Found in medulla oblongata
Has two centres inspiratory and expiratory
How does the respiratory control centre work ?
CHEMORECEPTORS: detect chemical change (blood acidity, high and low levels of O2 and CO2)
BARORECEPTORS: detect increase in bp
PROPRIORECEPTORS: detect change in muscle length (muscle spindle) and muscle tension (Golgi tendon organ)
These send signal to inspiratory centre which send signal to RCC which then sends signal down phrenic nerve causing and increase in inspiration
STRETCH RECEPTORS: prevent her inflation of lungs. If start to excessively stretch, impulses are sent to expiratory centre to induce expiration ( Hering Breur reflex)
This send signal to expiratory centre which send signal to RCC which then sends one to intercostal nerve causing there to be increase in expiration
Increased inspiration and expiration = increase tidal volume and breathing rate
Oxyhemoglobin dissociation curve:
O2 bind wi haemoglobin at lungs so high saturation levels
pO2 at muscles is low but pCO2 is high this causes O2 to dissociate from haemoglobin easier causing the curve to shift to the right known as the Bohr shift
What causes dissociation of O2 from haemoglobin ?
- Increase blood and muscle temp
- Increase acidity in blood due to CO2 and Hydrogen ions (Bohr effect)
- Decreased pO2 in muscle
- Increase pCO2 in muscle
What is A-VO2 diff ?
Diff between O2 content of arterial blood arriving at muscles/tissues and venous blood leaving
At rest A-VO2 diff is low
During exercise it’s high
How can performer increase A-VO2 diff ?
Increase muscle capillary density
Enhanced mitochondrial density
Improve haemoglobin levels
Improve myoglobin levels
How does having a greater A-VO2 diff impact performer ?
Increase VO2 max because muscles are able to extract and utilise O2
Define VO2 max
Max volume of O2 an individual can utilise during exercise per minute
Cardiac output X A-VO2 diff = VO2 max
