Human Physiology - Breathing and Exchange of Gases: Notes

The Respiratory System

1. Anatomy (NCERT class 11th Biology - Chapter 19)
   • Nasal passages
   • Pharynx
   • Larynx
   • Trachea
   • Bronchi
   • Bronchioles
   • Alveoli
2. Respiratory muscles (NCERT class 11th Biology - Chapter 19)
   • Diaphragm
   • Intercostal muscles

The Breathing Process

1. Mechanics of breathing (NCERT class 11th Biology - Chapter 19)
   • Inspiration
   • Expiration
   • Role of lungs in expansion and contraction
2. Factors influencing breathing rate and depth (NCERT class 11th Biology - Chapter 19)
   • Physical activity
   • Emotions
   • Respiratory ailments

Gas Exchange in the Lungs

1. Diffusion across the alveolar-capillary membrane (NCERT class 11th Biology - Chapter 19)
   • Oxygen
   • Carbon dioxide
2. Role of hemoglobin in transporting gases (NCERT class 11th Biology - Chapter 19)
   • Oxygen
   • Carbon dioxide
3. Partial pressures of gases in lungs and tissues (NCERT class 11th Biology - Chapter 19)
   • Oxygen
   • Carbon dioxide

Transport of Gases in the Blood

1. Hemoglobin’s role in binding gases (NCERT class 11th Biology - Chapter 19)
   • Oxygen
   • Carbon dioxide
2. Oxygen saturation and hemoglobin dissociation curves (NCERT class 11th Biology - Chapter 19)
3. Factors affecting hemoglobin affinity for oxygen (NCERT class 11th Biology - Chapter 19)
   • pH
   • Temperature
   • Partial pressures of gases

Regulation of Breathing

1. Respiratory center in medulla oblongata and pons (NCERT class 11th Biology - Chapter 19)
2. Influence of chemoreceptors and mechanoreceptors (NCERT class 11th Biology - Chapter 19)
3. Neural and hormonal factors (NCERT class 11th Biology - Chapter 19)
   • Vagus nerve
   • Carbon dioxide levels

Respiratory Disorders

1. Common disorders impacting breathing and gas exchange (NCERT class 12th Biology - Chapter 16)
   • Asthma
   • Chronic obstructive pulmonary disease (COPD)
   • Emphysema
   • Lung cancer
2. Underlying mechanisms and symptoms (NCERT class 12th Biology - Chapter 16)

Adaptations for Gas Exchange

1. Comparative study of respiratory adaptations in various organisms (NCERT class 11th and 12th Biology - Chapters 19, 21)
2. Aquatic organisms (NCERT class 12th Biology - Chapter 21)
   • Fish
   • Aquatic insects
3. Specialized structures and adaptations (NCERT class 12th Biology - Chapter 21)
   • Insects
   • Amphibians
   • Reptiles
   • Birds
   • Mammals