269 Respiration ⭐️

What are the two types of respiration

Pulmonary respiration

Cellular respiration

What is the purpose of pulmonary respiration

Ventilation

Exchange O2 and CO2 in the lungs

What is the purpose of cellular respiration

Uses O2 and produces CO2 by the tissues

What is ventilation

The mechanical process of moving air into and out of the lungs

What are the two pressure differences

Intrapulmonary pressure

Atmospheric pressure

What is inspiration

Occurs when volume of the lungs increases

Causes diaphragm to contract (thoracic cavity increases)

Control is located in the medullar oblongata

What is expiration

Occurs when volue of the lungs decreases

Causes diaphragm to relax (thoracic cavity decreases)

Control is located in the medullar oblongata

What is diffusion

Random movement of molecules from high concentration to low concentration

How is the respiratory system broken up

There the structural organization which has a upper and lower respiratory tract

Then there the functional organization which has the conducting zone and respiratory zone

What does air way resistance depend on

Pressure difference between the two ends of the airway

Resistance on diameter of airway

What is the equation for air flow

Air flow = P1 - P2 / Resistance

What is pulmonary ventilation

Movement of gas into and out of the lungs

What is the equation for venilation

V = VT x f

(VT - volime of gas moved per breath, f - frequency of breathing)

What is tidal volume (TV)

Amount of air inhaled or exhaled in 1 normal breath

What is inspiratory reserve volume (IRV)

Excess air that can be inhaled with maximum effort (after normal breath)

What is expiratory reserve volume (ERV)

Exess air that can be exhaled with maximum effort (after normal breath)

What is residual volume (RV)

Air remaining in the lungs after maximum expiration (can never be fully voluntarily exhaled)

What is vital capacity (VC)

Air that can be forcefully exhaled after maximum inspiration

ERV + TV + IRV

What is inspiratory capacity (IC)

Maximum amount of air that can be inhaled after normal expiration

TV + IRV

What is functional residual capacity (FRC)

Air remaining in the lungs after normal expiration

RV + ERV

What is total lung capacity

Maximum amount of air in the lungs at the end of maximum inspiration

RV + VC

What is the normal resting respiration vs during exercise

Resting - 12-17 breaths/minute

Exercise - 45-65 breaths/minute

What is alveolar ventilation

Portion of the tidal wave that reaches alveolar compartment - portion of tidal wave that does not reach alveolar compartment (gas trapped within anatomical dead space)

What is used to measure lung volume

A spirometry

What is Dalton’s Law

Total pressure of gas = sum of pressure that each gas would exert independently

What is the equation of air pressure

Pair = PO2 + PCO2 +PN2

What is Fick’s law equation

V gas = A/T x D x P (P1 - P2)

(A - tissue area, T - thickness, D - diffusion coefficient, P1-P2 - differenace in partial pressure)

Why is there a differenace of diffusion between oxygen and carbon dioxide

They are different in size and have different coefficients

What is the equation for partial pressure of O2 and CO2

PAO2 = (PB x FIO2) - 47 mmHG

(PB - biometric pressure, FIO2 - factors of inspired oxygen)

What circuit does blood use to go to the lungs

Pulmonary circuit

What is the ventilation-perfusion relationship (V/Q)

Maintains a balanced ratio of matching airflow (V) to blood flow (Q)

Ideal is 1.0

• underperfused V/Q < 1.0

• overperfused V/Q > 1.0

Light-moderate exercise improves V/Q ratio

Heavy exercise may result in V/Q inequality

What two ways is oxygen transported within the blood

Oxyhemoglobin - being bound to hemoglobin (99% is transported this way)

Deoxyhemoglobin - not bound to hemoglobin

What the amount of oxygen that can be transported depended on

The hemoglobin concentration

What is the oxyhemoglobin dissociation curve

Sigmoidal curve (S shaped)

This curve relates to how much oxygen we can take into the tissue at any given partial pressure

Factors that affect this curve include:

• pH (decrease in pH = lower hemoglobin-oxygen binidng strength, curve shifts right)

• Temperature (increasing blood temp = lower hemoglobin-oxygen binding strength, curve shifts right)

  • Diphosphoglyceric acid

What is the deoxygemoglobin oxyhemoglobin relationship

Deoxygemoglobin + O2 ←> oxyhemoglobin

• The direction of reaction depends on pressure of oxygen in blood and strength of binding between hemoglobin and O2W

What is myoglobin

Serves as a O2 binding protein in skeletal muscle

• Has higher binding strength for O2 than hemoglobin

• Stores O2

• Under very low conditions of oxygen during max exercise, myoglobin will give up O2 for the production of ATP in the electron transport chain

What are the three ways CO2 can be transported in the blood

Dissolved in plasma

Bound to hemoglobin

Bicarbonate

What is the carbonic anhydrase equation

←———————————————-Lung

CO2 + H2O ——→ H2CO3 → H + HCO3-

Muscle ————————————→

How does CO2 transport in the blood at the tissue level

H+ binds to hemoglobin

HCO3- diffuses out of RBC into plasma

Cl- diffuses into RBC (Chloride shift)

How does CO2 transport in the blood at the lung level

O2 binds to hemoglobin (drives off H+)

Reaction reverses to release CO2

Cl- diffuses into RBC (chloride shift)

What is hyperventilation

Increased ventilation = CO2 exhalation

It reduces PCO2 and H+ concentration (pH increases)

What is hypoventilation

Decreased ventilation = CO2 buildup

It increases PCO2 and H+ concentration

What ventilatory changes occur during exercise

• Ventilation increases in proportion to the exercise intensity

• It also increases during prolonged submaximal exercise in hot environment + during graded potential

How does PCO2 react when VE drifts upward during a hot environment exercise

It remains constance during to the changes in CO2 stimulate cause the brain to ventilate more

How are the buffering systems different in trained vs untrained

Training has increased buffering capacity

Untrained has reduced buffering capacity

How is inspiration controlled

The control system is located in the medulla oblongata

Output from the respiratory control center regulates motor neurons in the spinal cord that control respiratory muscles. Primary neural pacemaker responsible for inspiration is the preBotzinger complex

How is expiration controlled

The control system is located in the medulla oblongata

Input to the respiratory control center from both humoral chemoreceptors and neural sources (higher brain centers and afferent pathways. Ex. muscle mechanoreceptors and chemoreceptors)

What are the central chemoreceptors sensitive to

PCO2 and H+ concentration in cerebrospinal fluid

What are the peripheral chemoreceptors sensitive to

PO2, PCO2, H+ and K+ in the blood

What are muscle mechanoreceptors

Muscle spindles, golgi tendon organs, joint pressure receptors

What are muscle chemoreceptors

Sensitive to K+ and H+ concentrations

How does endurance training imapct ventialtion during exercise

It causes ventilation to be lower