This category focuses on the anatomy and function of the human respiratory system, including organs like the lungs, trachea, and diaphragm. It includes explanations and practice questions to help understand how these structures work together for respiration.
The pharynx serves as a common passage for both air (to the lungs) and food (to the esophagus).
Ref: NCERT Class 11 Biology Chapter 14: Breathing and Exchange of Gases Respiratory Organs and Human Respiratory System
Inhalation occurs when intrapulmonary pressure falls below atmospheric pressure, allowing air to flow into the lungs.
Ref: NCERT Class 11 Biology Chapter 14: Breathing and Exchange of Gases Respiratory Organs and Human Respiratory System
The larynx is known as the voice box because it contains the vocal cords responsible for sound production.
Ref: NCERT Class 11 Biology Chapter 14: Breathing and Exchange of Gases Respiratory Organs and Human Respiratory System
The nasal chamber warms, filters, and humidifies inhaled air before it reaches the lungs.
Ref: NCERT Class 11 Biology Chapter 14: Breathing and Exchange of Gases Respiratory Organs and Human Respiratory System
The trachea is supported by incomplete cartilaginous rings that prevent its collapse during breathing.
Ref: NCERT Class 11 Biology Chapter 14: Breathing and Exchange of Gases Respiratory Organs and Human Respiratory System
The larynx, also known as the voice box, contains vocal cords responsible for sound production.
Ref: NCERT Class 11 Biology Chapter 14: Breathing and Exchange of Gases Respiratory Organs and Human Respiratory System
The pleural membranes surround the lungs and reduce friction during breathing by secreting pleural fluid.
Ref: NCERT Class 11 Biology Chapter 14: Breathing and Exchange of Gases Respiratory Organs and Human Respiratory System
A decrease in temperature increases the oxygen-binding affinity of hemoglobin, promoting oxygen uptake in the lungs.
Ref: NCERT Class 11 Biology Chapter 14: Breathing and Exchange of Gases Respiratory Organs and Human Respiratory System
Bronchioles do not have cartilaginous rings; instead, they are composed of smooth muscle, which allows them to constrict or dilate.
Ref: NCERT Class 11 Biology Chapter 14: Breathing and Exchange of Gases Respiratory Organs and Human Respiratory System
During expiration, the diaphragm relaxes and moves upward, decreasing thoracic volume and increasing pressure.
Ref: NCERT Class 11 Biology Chapter 14: Breathing and Exchange of Gases Respiratory Organs and Human Respiratory System
The nasal chamber humidifies, filters, and warms inhaled air before it reaches the lungs.
Ref: NCERT Class 11 Biology Chapter 14: Breathing and Exchange of Gases Respiratory Organs and Human Respiratory System
The diaphragm is a dome-shaped muscle that separates the thoracic and abdominal cavities and plays a key role in respiration.
Ref: NCERT Class 11 Biology Chapter 14: Breathing and Exchange of Gases Respiratory Organs and Human Respiratory System
