[Biology][Practical-11] Respiratory Physiology Questions

  • The upper respiratory tract is composed of: the nose + pharynx + larynx

  • The lower respiratory tract goes from trachea to alveolus

  • The right lung is made up of 3 lobes and the left one 2 lobes

  • Muscles of expiration are internal intercostals + diaphragm + accessory muscles

  • Quiet breathing is a passive process

  • Why do we use spirometry? To diagnose an illness or to determine progress in a treatment

  • What volume can NOT be determined with spirometry ? residual volume

  • What volumes can be determined by spirometry ?

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  • Gas exchange occurs in the alveoli

  • Surfactant fluid is synthesized by pneumocytes II

  • Surfactant fluid helps to reduce surface tension

  • Capacity of gas exchange is increased by the rich capillary network

  • Muscles of inspiration are external intercostals + diaphragm + accessory muscles

  • What is tidal volume? volume of air moved during quiet breathing

  • Lung volumes are influenced by height, location, and lifestyle

  • How does exercise affect ventilation?

    • it increases the ventilation rate due to the greater frequency of breaths
    • it increases the tidal volume due to the increase of the depth of breathing
  • What is VO2max? the maximum speed at which oxygen can be absorbed and delivered to body tissues

  • Explain the concepts of oxygen deficit and oxygen debt

  • What is the maximum volume inhaled called? inspiratory reserve volume

  • What is the maximum volume exhaled called? expiratory reserve volume

  • The pontine respiratory group is made of the pneumotaxic center and the apneustic center

  • How does the breathing center work?

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  • What is the difference between ventilation and perfusion ?

    • Ventilation is the air that reaches the alveoli
    • Perfusion is the flow of blood into the alveoli
  • Ventilation helps to maintain a concentration gradient of oxygen

  • O2 levels are high in the alveoli and diffuse into the bloodstream

  • CO2 levels are low in the alveoli and diffuse from the bloodstream

  • Spirometry measures the amount and rate of air that a person breathes

  • How is CO2 transported?

  1. bound to Hb and therefore forms HbCO2
  2. dissolved in water
  3. diffuses in the red blood cell and converted into carbonic acid → 75% of it
  • Hb has a lower affinity with oxygen than HbO8

  • Explain the concept of cooperative binding

  • How is blood pH regulated?

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  • Amino-acids are zwitterions which means that that they can either be positively or negatively charged

  • Lactic acid causes muscle ache, rapid breathing, and stomach pain

  • What is the difference between hemoglobin and myoglobin?

  • Number of chains
  • Number of oxygen bound
  • Capacity to do cooperative binding
  • Oxygen partial pressure diagram
  • The respiration center is located inside the medulla oblongata

  • Explain the Bohr effect

  • Hemoglobin can bind 4 oxygens

  • The affinity of hemoglobin with oxygen depends on how saturated it is (number of oxygen bound)

  • Central chemoreceptors are located in the medulla and peripheral chemoreceptors are located inside the carotid and aortic arch

  • The chemoreceptors are sensitive to PaCO2 and blood pH

  • The neurons in the respiratory center are called dorsal, ventral, and pontine respiratory group

  • Mb has a higher affinity for oxygen than adult Hb and consequently becomes saturated at lower oxygen levels

  • The Bohr shift explains the increased release of oxygen by Hb

  • Explain how we go from CO2 in the lungs to bicarbonate and vice versa

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  • Partial pressure occurs when there is more than one gas in one structure

  • Total pressure is equal to the sum of all the partial pressures

  • Why do athletes train in high altitudes?

    • production of red blood cells increases to make up for the lack of oxygen
    • they have more Hb with a higher affinity for oxygen
    • vital capacity is raised
    • muscles produce more myoglobin
    • kidneys produce alkaline urine to remove the excess bicarbonates: this acts as a buffer for the blood pH
  • Myoglobin is found in skeletal muscles tissues

  • Myoglobin can bind 1 oxygen

10 Likes

Hello, can I ask why the chemoreceptors aren’t sensitive to PaO2 but it is only sensitive to PaCO2 and blood pH? Thank you very much!

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Hey I don’t understand this part😅, can you please explain what does it mean ?

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Hi, according to the lesson, the central chemoreceptors are sensitive to PaCO2 (decreasing pH) while peripheral ones are sensitive to PaO2 (increasing pH).

3 Likes

Hey, with more O2 molecules joined to haemoglobin, its affinity for O2 increases. Although HbO8 is already fully saturated with oxygen (has 4 O2 molecules), it theoretically has a higher affinity for O2 than Hb on its own, which does not have any O2.

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