Respiration is controlled by nervous and chemical regulation'

1
Respiration is controlled by nervous and chemical
regulation.
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I- Nervous Regulation
A-Momentary regulation as during swallowing or
speech, there is momentary stoppage of respiration
B-Continuous regulation Through some reflex

• Hering Breuer reflex
• Reflexes from baroreceptors
• Reflex from right atrium (Harrisons reflex)

2
II)- Chemical Regulation
Through changes in CO2 tension, O2 tension, and
hydrogen ion concentration of blood (pH)
1-Effect of CO2

• CO2 is natural stimulus for respiration
• Increase in CO2 tension will stimulate
  respiration reflex

2-Effect of O2
Decrease in O2 tension will stimulate respiration
and vice versa.
3-Effect of pH of Blood

• Decrease in pH (acidosis) will stimulate
  respiration, while increased pH (Alkalosis) will
  inhibit respiration

3
Some Respiratory Defects

• Dyspnea Means difficulty of respiration.
• Apnea Means stoppage of respiration.
• Hypoxia Means decrease in O2 supply to the
  tissues.
• Cyanosis Means appearance of bluish colour of
  skin and mucous membrane due to
  effective oxygenation.
• Asphyxia If external respiration ceases.
• Anoxia Means complete deprivation of oxygen.

4
OTHER FUNCTIONS OF THE RESPIRATORY SYSTEM
A) Pulmonary Embolization B) Lung Defense
Mechanisms C) Metabolic Endocrine Functions of
the Lungs
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